Starpower: The U.S. and the International

Quest for Fusion Energy

October 1987

NTIS order #PB88-128731
Recommended Citation:

U.S. Congress, Office of Technology Assessment, Starpower: The U.S. and the Internnational Quest for Fusion Energy, OTA-E-338 (Washington, DC: U.S. Government Printing

Office, October 1987).

Library of Congress Catalog Card Number 87-619854

For sale by the Superintendent of Documents

U.S. Government Printing Office, Washington, DC 20402-9325

(order form can be found in the back of this report)
.

Foreword

Fusion research, offering the hope of an energy technology with an essentially unlimited supply of fuel and relatively attractive environmental impacts, has been conducted worldwide for over three decades. In the United States, increased budgetary

pressures, along with a decreased sense of urgency, have sharpened the competition

for funding between one research program and another and between energy research

programs and other components of the Federal budget. This report, requested by the

House Committee on Science, Space, and Technology and endorsed by the Senate

Committee on Energy and Natural Resources, reviews the status of magnetic confinement fusion research and compares its progress with the requirements for development of a usefuI energy technology. The report does not analyze inertial confinement

fusion research, which is overseen by the House and Senate Armed Services Committees.

OTA analyzed the magnetic fusion research program in three ways: (1) as an energy

program, by identifying important features of the technology and discussing its possible role in the energy supply mix; (2) as a research program, by discussing its role in

training scientists and developing new fields of science and technology; and (3) as an

international program, by reviewing its history of international cooperation and its

prospects for even more extensive collaboration in the future.

OTA could not have conducted this work without the valuable assistance it received from many organizations and individuals. I n particular, we would like to thank

the advisory panel members, workshop participants, and outside reviewers, who provided guidance and extensive critical reviews to ensure the accuracy of the report.

Responsibility for the final report, however, rests solely with the Office of Technology

Assessment.
Magnetic Fusion Research Advisory Panel

William Carey, Panel Chair

Executive Officer, American Association for the Advancement of Science

Ellen Berman

Executive Director

Consumer Energy Council of America

Linda Cohen

Assistant Visiting Professor of Economics

University of Washington

Paul Craig

professor of Physics

Department of Applied Science

University of California, Davis

Betty Jensen

Nuclear and Environmental Program Manager

Research and Development

Public Service Electric & Gas Co.

Hans Landsberg

Senior Fellow Emeritus

Resources for the Future

Lawrence Lidsky

Professor of Nuclear Engineering

Massachusetts Institute of Technology

Harold Forsen Irving Mintzer

Manger of Research and Development Senior Associate

Bechtel National, Inc. World Resources Institute

T. Kenneth Fowler Robert park

Associate Director Executive Director

Magnetic Fusion Energy Office of Public Affairs

Lawrence Livermore National Laboratory American Physical Society

Melvin Gottlieb

Director Emeritus

Princeton Plasma Physics Laboratory

L. Charles Hebel

Manager, Research Planning

Corporate Research Technical Staff

Xerox Corp.

Robert Hirsch

Vice President

Arco Oil & Gas Co.

Leonard Hyman

Vice President

Merrill Lynch Capital Markets

Murray Rosenthal

Associate Laboratory Director for Advanced

Energy Systems

Oak Ridge National Laboratory

Eugene Skolnikoff

Director

Center for International Studies

Massachusetts Institute of Technology

Herbert Woodson

Director

Center for Energy Studies

University of Texas, Austin

NOTE: OTA appreciates and is grateful for the valuable assistance and thoughtful critiques provided by the advisory panel

members. The panel does not, however, necessarily approve, disapprove, or endorse this report. OTA assumes full

responsibility for the report and the accuracy of its contents.

iv
OTA Project Staff on Magnetic Fusion Research

Lionel S. Johns, Assistant Director, OTA

Energy, Materials, and International Security Division

Peter D. Blair, Energy and Materials

Gerald L. Epstein, Project

Program Manager

Director

Dina K. Washburn

Contractors

Wilfrid Kohl Leonard Lynn

Paul Josephson Lynn Powers

Fusion Power Associates

Battelle Pacific Northwest Laboratories

Administrative Staff

Lillian Chapman Linda Long Barbara J. Carter
Workshop Participants and Other Outside Reviewers

Workshop 1: Fusion Research

Panelists

Robert Seamans, Workshop Chair

Senior Lecturer

Aeronautics and Astronautics

Department

Massachusetts Institute of

Technology

Sibley Burnett

General Manager

Applied Superconetics Division

GA Technologies

Ronald Davidson

Director

Plasma Fusion Center

Massachusetts Institute of

Technology

Stephen Dean

President

Fusion Power Associates

Harold Forsen

Manager of Research and

Development

Bechtel National, Inc.

T. Kenneth Fowler

Associate Director

Magnetic Fusion Energy

Lawrence Livermore National

Laboratory

Harold Furth

Director

Princeton Plasma Physics

Laboratory

Melvin Gottlieb

Director Emeritus

Princeton Plasma Physics

Laboratory

Robert Hirsch

Vice President

Arco Oil & Gas Co.

Robert Krakowski

Group Leader

Systems Study Group

Los Alamos National Laboratory

Lawrence Lidsky

Professor of Nuclear Engineering

Massachusetts Institute of

Technology

Chuan Sheng Liu

Chairman

Department of Physics and

Astronomy

University of Maryland, College

Park

Thomas Ratchford

Associate Executive Officer

American Association for the

Advancement of Science

John Sheffield

Associate Director for

Confinement

Fusion Energy Division

Oak Ridge National Laboratory

Herbert Woodson

Director

Center for Energy Studies

University of Texas, Austin

Contributor

N. Anne Davies

Assistant Director

Office of Fusion Energy

U.S. Department of Energy

Workshop II: International

Cooperation

Eugene Skolnikoff, Workshop

Chair

Director

Center for International Studies

Massachusetts Institute of

Technology

Harold Benglesdorf

Vice President

International Group

International Energy Associates

Limited

Diana Bieliauskas

Program Officer

Office of Soviet and East European

Affairs

National Academy of Sciences

Justin Bloom

President

Technology International, Inc.

Judy Bostock

Operations Research Analyst

U.S. Office of Management and

Budget

Melvin Gottlieb

Director Emeritus

Princeton Plasma Physics

Laboratory

Paul Huray

Senior Policy Analyst

General Science

U.S. Office of Science and

Technology Policy

Paul Josephson

Program in Science, Technology

and Society

Massachusetts Institute of

Technology

Wilfrid Kohl

Director

International Energy Program

Johns Hopkins School of

Advanced International Studies

Linda Lubrano

Professor

School of International Service

The American University

Leonard Lynn

Assistant Professor

Department of Social and

Decision Sciences

Carnegie-Mellon University

Charles Newstead

Foreign Affairs Officer

Bureau of Oceans and

International Environmental and

Scientific Affairs

U.S. Department of State

Douglas R. Norton

Chief of International Planning

and Program Office

U.S. National Aeronautics and

Space Administration

Herman Pollack

Research Professor

Department of International Affairs

George Washington University

vi
Michael Roberts

Director

International Programs

Office of Fusion Energy

U.S. Department of Energy

Richard Samuels

Professor of Political Science

Massachusetts Institute of

Technology

U. John Sakss

Chief of International Program

Support Office

U.S. National Aeronautics and

Space Administration

Workshop Ill: Energy Context

Robert Fri, Workshop Chair

President

Resources for the Future

Truman Anderson

Director

Program Planning and Analysis

Oak Ridge National Laboratory

Charles Backus

Assistant Dean

College of Engineering and

Applied Science

Arizona State University

Charles Berg

Professor and Head of Department

Department of Mechanical

Engineering

Northeastern University

Jan Beyea

Vice President of Science

National Audubon Society

Paul Craig

Professor of Physics

Department of Applied Science

University of California, Davis

Daniel Dreyfus

Vice President

Strategic Analysis and Energy

Forecasting

Gas Research Institute

James A. Edmonds

Senior Research Economist

Battelle Pacific Northwest

Laboratories

Harold Feiveson

Center for Energy and

Environmental Studies

Princeton University

Bill Keepin

School of Engineering and Applied

Science

Princeton University

Carlo La Porta

Director of Research

Solar Energy Industries Association

René MaIès

Senior Vice President and

Principal

Decision Focus, Inc.

Michael Mauel

Assistant Professor

Department of Applied Physics

and Nuclear Engineering

Columbia University

Irving Mintzer

Senior Associate

World Resources Institute

Eric Reichl

Retired, Conoco Coal Corp.

Arthur Rosenfeld

Director

Center for Building Science

Lawrence Berkeley Laboratory

John Siegel

Vice President

Atomic Industrial Forum

Don Steiner

Institute Professor

Department of Nuclear

Engineering and Engineering

Physics

Rensselaer Polytechnic Institute

Other Outside Reviewers

Mohamed Abdou

University of California, Los

Angeles

Charles Baker

Argonne National Laboratory

David Baldwin

Lawrence Livermore National

Laboratory

Richard Barnes

U.S. National Aeronautics and

Space Administration

Lee Berry

Oak Ridge National Laboratory

Joan Lisa Bromberg

Laser History Project

Daniel Chavardes

Embassy of France

Daniel Cohn

Massachusetts Institute of

Technology

Donald L. Cook

Sandia National Laboratories

Tony Cox

Embassy of the United Kingdom

John Deutch

Massachusetts Institute of

Technology

Thomas J. Fessenden

Lawrence Berkeley Laboratory

Thomas G. Finn

U.S. Department of Energy

William Hogan

Lawrence Livermore National

Laboratory

John Holdren

University of California, Berkeley

Paul Koloc

Phaser Corp.

Dennis Mahlum

Battelle Pacific Northwest

Laboratories

George Miley

University Fusion Associates

David Overskei

GA Technologies

John Richardson

National Research Council

Marshall Rosenbluth

University of Texas, Austin

Richard Rowberg

Congressional Research Service

Mike Saltmarsh

Oak Ridge National Laboratory

vii
John Santarius F. Robert Scott Albert Teich

University of Wisconsin, Madison Retired, Electric Power Research American Association for the

Institute Advancement of Science

Winfried Schmidt

Karlsruhe Nuclear Research Center Richard Siemons Robert W. Turner

Los Alamos National Laboratory U.S. Department of Defense

Ken Schultz Joel Snow Wim Van Deelen

GA Technologies U.S. Department of Energy European Communities Delegation
.

Contents

Chapter Page

I, Executive Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

2. Introduction and Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

3. History of Fusion Research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

4. Fusion

5. Fusion

6. Fusion

7. Fusion

8. Future

Appendixes

A.

B.

c.

D.

Science and Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

as

as

as

an Energy Program. . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . .105

a Research Program . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131

an International Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . , .155

Magnetic Fusion Program . . . . . . . . . . . ..................189

Page

Non-Electric Applications for Fusion . . . . . . . . . . . . . . . . . . . . . ................201

Other Approaches to

Data for Figures . . . .

List of Acronyms and

Fusion. .

. . . . . . . .

Glossary

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .........227

ix
Chapter 1

Executive Summary
CONTENTS

Page

Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Potential Role of Fusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The Policy Context . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

A Quick Fusion Primer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The Fusion Reaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The Feasibility of Fusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Probability of Success . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

History of Magnetic Confinement Fusion Research . . . . . . . . . . . . . . . . . . . . . . . .

1950s and 1960s . . . . . . . . . . .

1970s and 1980s . . . . . . . . . . .

Fusion Science and Technology

Confinement Concepts . . . . . .

Reactor Development . . . . . . .

Future Plans and Facilities . . .

Schedules and Budgets . . . . . .

Status of the World Programs.

Fusion as an Energy Program . . .

Safety . . . . . . . . . . . . . . . . . . . .

Environmental Characteristics.

Nuclear Proliferation Potential

Resource Supplies . . . . . . . . . .

cost. . . . . . . . . . . . . . . . . . . . . .

Fusion’s Energy Context . . . . .

Fusion as a Research Program . .

Near-Term Benefits . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Near-Term Financial and Personnel Needs . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Participation in the Magnetic Fusion Program , . . . . . . . . . . . . . . . . . . . . . . . . .

Fusion as an International Program. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Opportunities for Increased Collaboration ., . . . . . . . . . . . . . . . . . . . . . . . . . . .

Benefits and Liabilities of Cooperation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Obstacles to International Cooperation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The International Thermonuclear Experimental Reactor . . . . . . . . . . . . . . . . . .

Figures

3

3

3

4

6

6

8

8

8

8

9

11

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15

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17

18

18

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24

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Figure No. Page

l-1. Historical Magnetic Fusion R&D Funding, 1951-87 (in 1986 dollars) . . . . . . 4

1-2, Historical Magnetic Fusion R&D Funding, 1951-87 (in current dollars) . . . . 5

1-3.The D-T Fusion Reaction and a Fission Reaction . . . . .

1-4. Systems in a Fusion Electric Generating Station . . . . . .

1-5. Systems in the Fusion Power Core. . . . . . . . .

l-6. Annual Appropriations of DOE Civilian R&D

Table

Table No.

l-1.Classification of Confinement Concepts. . . . .

. . . . . . . .

Programs

. . . . . . . .

. . . . . . . . . . . . . . . . . 7

. . . . . . . . . . . . . . . . . 13

. . . . . . . . . . . . . . . . . 14

. . . . . . . . . . . . . . . . . 22

Page

. . . . . . . . . . . . . . . . . 12
Chapter 1

Executive Summary

OVERVIEW

Potential Role of Fusion

If successfully developed, nuclear fusion could

provide humanity with an effectively unlimited

source of electricity that has environmental and

safety advantages over other electric energy technologies. However, it is too early to tell whether

these advantages, which could be significant, can

be economically realized. Research aimed at developing fusion as an energy source has been

vigorously pursued since the 1950S, and, despite

considerable progress in recent years, it appears

that at least three decades of additional research

arid development will be required before a prototype commercial fusion reactor can be demonstrated.

The Policy Context

The budget for fusion research increased more

than tenfold in the 1970s, due largely to growing public concern about environmental protection and uncertainty in long-range energy supply. However, a much-reduced sense of public

urgency in the 1980s, coupled with the mounting Federal budget deficit, halted and then

reversed the growth of the fusion budget. Today,

the fusion program is being funded (in 1986 dollars) at about half of its peak level of a decade

ago (see figures 1-1 and 1-2).

The change in the fusion program’s status over

the past 10 years has not resulted from poor technical performance or a more pessimistic evaluation of fusion’s prospects. On the contrary, the

program has made substantial progress. However, the disappearance of a perceived need for

near-term commercialization has reduced the

impetus to develop commercial fusion energy

and has tightened pressure on fusion research

budgets. Over the past decade, the fusion program has been unable to maintain a constant

funding level, much less command the substantial funding increases required for next-generation

facilities. In fact, due to funding constraints, the

program has been unable to complete and operate some of its existing facilities.

The Department of Energy (DOE) manages the

U.S. fusion program, and its goal is to evaluate

fusion’s technological feasibility–to determine

whether or not a fusion reactor can be designed

and built—early in the 21st century. A positive

evaluation would enable a decision to be made

at that time to construct a prototype commercial

reactor. However, this schedule cannot be met

under existing U.S. fusion budgets. The DOE

plan requires either that U.S. budgets be increased substantially or that the world fusion

programs collaborate much more closely on fusion research.

Choices made over the next several years can

place the U.S. fusion program on one of four fundamentally different paths, which are discussed

more thoroughly in chapter 8 of this report:

1

2.

3.

With substantial funding increases, the fusion program could complete its currently

mapped-out research effort domestically, permitting decisions to be made early in the

next century concerning fusion’s potential

for commercialization.

At only moderate increases in U.S. funding

levels, the same results as above might be

attainable—although possibly somewhat

delayed–if the United States can work with

some or all of the world’s other major fusion programs (Western Europe, Japan, and

the Soviet Union) at an unprecedented level

of collaboration.

Decreased funding levels, or current funding levels in the absence of extensive collaboration, would require modification of

the program’s overall goals. At these constrained funding levels, U.S. evaluation of

fusion as an energy technology would be

delayed.

3
4 ● Starpower: The u.s. and the International Quest for Fusion Energy

Figure 1-1 .—Historical Magnetic Fusion R&D Funding, 1951087 (in 1986 dollars)

1955 1960 1965 1970 1975 1980 1985

Year

SOURCE: U.S. Department of Energy, Office of Energy Research, letter to OTA project staff, Aug. 15, 1986.

4. If fusion research ceased in the United

States, the possibility of domestically developing fusion as an energy technology would

be foreclosed unless and until funding were

restored. Work would probably continue

abroad, although possibly at a reduced pace; ●

resumption of research at a later time in the

United States would be possible but difficult.

Findings

Here are some of the overall findings from

OTA’s analysis:

● Experiments now built or proposed should, ●

over the next few years, resolve most of the

major remaining scientific uncertainties regarding the fusion process. If those experiments do not uncover major surprises, it is

likely–although by no means certain–that

the engineering work necessary to build an

electricity-producing fusion reactor can be

completed successfully.

Additional scientific understanding and technological development is required before fusion’s potential can be assessed. It will take

at least 20 years, under the best circumstances, to determine whether construction

of a prototype commercial fusion reactor will

be possible or desirable; additional time beyond then will be required to build, operate, and evaluate such a device.

It is now too early to tell whether fusion reactors, once developed, can be economically competitive with other energy technologies.
C/7. I.—Executive Summary “ 5

150

100

50

0

Figure 1-2.—Historical Magnetic Fusion R&D Funding, 1951-87 (In current dollars)

1955 1960 1965 1970 1975

Year

SOURCE: U.S. Department of Energy, Office of Energy Research, letter to OTA project staff, Aug. 15, 1986.

1980 1985

● Demonstration and commercialization of fusion power will take several decades after

completion of the research program. Even ●

under the most favorable circumstances, it

does not appear likely that fusion will be able

to satisfy a significant fraction of the Nation’s

electricity demand before the middle of the

21st century.

• With appropriate design, fusion reactors

could be environmentally superior to other ●

nuclear and fossil energy production technologies. Unlike fossil fuel combustion, fusion reactors do not produce carbon dioxide

gas, whose accumulation in the atmosphere

could affect world climate. Unlike nuclear

fission–the process utilized in existing nuclear powerplants—fusion reactors should

not produce high-level, long-lived radioactive wastes.

One of the most attractive features of fusion

is its essentially unlimited fuel supply. The

only resources possibly constraining fusion’s

development might be the materials needed

to build fusion reactors. At this stage of development, it is impossible to determine

what materials will eventually be developed

and selected for fusion reactor construction.

If fusion technology is developed successfully, it should be possible to design fusion

reactors with a higher degree of safety assurance than fission reactors. It may be possible to design fusion reactors that are incapable of causing any immediate off-site fatalities

in the event of malfunction, natural disaster,

or operator error.
6 ● Starpower: The us and the Intemational Quest for fusion Energy

●

●

●

●

potential problems with other major sources

of electricity—fossil fuels and nuclear

fission–provide incentives to develop alternate energy technologies as well as to substantially improve the efficiency of energy

use. Fusion is one of several technologies being explored.

It is unlikely that major, irreversible energy

shortages will occur early in the next century that could only be ameliorated by the

crash development of fusion power. There

is little to be gained—and a great deal to be

lost–by introducing fusion before its potential economic, environmental, and safety capabilities are attained. Even if difficulties with

other energy technologies are encountered

that call for the urgent development of an

alternative source of energy supply, that

alternative must be preferable in order to be

accepted. It would be unwise to emphasize

one fusion feature—economics or safety or

environmental advantages—over the others

before we know which aspect will be most

important for fusion’s eventual acceptance.

Due to the high risk and the long time before any return can be expected, private industry has not invested appreciably in fusion

research and cannot be expected to do so

in the near future. But, unless the government decides to own and operate fusion

generating stations, the responsibility for fusion research, development, and commercialization must be transferred to private industry at some stage. The nature and timing

of this transition are highly controversial.

Fusion research has provided a number of

●

●

●

A QUICK FUSION

near-term benefits such as development of

plasma physics, education of trained researchers, contribution to “spin-off” technologies, and support of the scientific stature of the United States. However, fusion’s

contributions to these areas do not imply that

devoting the same resources to other fields

of study would not produce equivalent benefits. Therefore, while near-term benefits do

provide additional justification for conducting research, it is difficult to use them to

justify one field of study over another.

Fusion research has a long history of successful and mutually beneficial international cooperation, If this tradition can be extrapolated in the future to an unprecedented level

of collaboration, much of the remaining cost

of developing fusion power can be shared

among the world’s major fusion programs.

International collaboration cannot substitute

for a strong domestic research program. If

the domestic program is sacrificed to support international projects, the rationale for

collaboration will be lost and the ability to

conduct it successfully will be compromised.

Agreeing to collaborate on fusion research,

both within the U.S. Government and between the U.S. Government and potential

partners, will require sustained support at the

highest levels of government. A variety of potential difficulties associated with large-scale

collaborative projects will have to be resolved, and presidential support will be required. If these difficulties can be resolved,

the benefits of successful collaboration are

substantial.

The Fusion Reaction isotopes; two of them—deuterium (D) and tritium

(T)–in combination work the best in fusion rein a fusion reaction, the nuclei–or central actions. The kinetic energy released in the D-T

cores—of light atoms combine or fuse together;

. . reaction can be converted to heat, which in turn

when they do, energy is released. In a sense, tu- can be used to make steam to drive a turbine to

sion is the opposite of fission, the process utilized generate electricity. in existing nuclear powerplants (see figure 1 -3),

in which energy is released when a heavy nucleus But a fusion reaction cannot happen unless cer- splits into smaller pieces. tain conditions are met. To fuse hydrogen nuclei

The lightest atom, hydrogen, is the easiest one together, the nuclei must be heated to approxito use for fusion. Hydrogen has three forms, or mately 100 million degrees Celsius (C). At these
.

Ch. I.—Executive Summary ● 7

Figure 1-3.—The D-T Fusion Reaction and a Fission Reaction
8 ● Starpower: The U.S. and the International Quest for Fusion Energy

temperatures, matter exists as plasrna, a state in

which atoms are broken down into electrons and

nuclei. Keeping a plasma hot enough for a long

enough period of time, and effectively confining

it, are crucial for generating fusion power.

While no solid container can withstand the

heat of a plasma, magnetic fields may be able to

confine a plasma successfully. This assessment

discusses magnetic confinement research and the

various magnetic field configurations that look

promising for producing fusion power.

More detail on the basics of fusion power can

be found in chapter 2.

The Feasibility of Fusion

Before fusion powerplants can generate electricity, fusion must be proven technologically and

commercially feasible.

Technological feasibility will require that both

scientific feasibility and engineering feasibility be

shown. Scientists must bring fusion reactions to

breakeven, the point at which at least as much

energy is produced as must be input to maintain

the reaction. Existing experiments are expected

to reach this long-elusive milestone by 1990. Beyond breakeven, scientists have an even harder

but more important task of creating high energy

gain–energy output that is many times higher

than the energy input. Only when high-gain reactions are produced will the scientific feasibility

of the fusion process be demonstrated. If a highgain reaction reaches ignition, it will sustain itself even when the external heat is turned off.

Once scientific feasibility of fusion as a potential energy source is established, the engineering development necessary to develop fusion reactors must be completed. Engineering feasibility

denotes the successful development of reliable

components, systems, and subsystems for operating fusion reactors.

Scientific and engineering feasibility, although

involving different issues, are interdependent.

Demonstrating either one will require advances

to be made in basic scientific understanding as

well as in technological capability.

The goal of fusion research is to prove fusion’s

technological feasibility so that its commercial

feasibility is likely. To be marketable, fusion power must be socially and environmentally acceptable and economically attractive compared to its

competitors, and it must meet regulatory and

licensing requirements.

Probability of Success

Experiments now existing or proposed to be

built should be sufficient, within the next few

years, to demonstrate fusion’s scientific feasibility. If these experiments do not uncover unfavorable surprises, it appears likely–although not certain—that fusion’s engineering feasibility can be

subsequently established. Most of the technological and engineering challenges to designing and

building a reactor have been identified. However, it cannot yet be determined whether or not

a fusion reactor will be commercially attractive.

HISTORY OF MAGNETIC CONFINEMENT FUSION RESEARCH

1950s and 1960s

From 1951 until 1958, fusion research was conducted by the U.S. Atomic Energy Commission

(AEC) in a secret program code-named “Project

Sherwood.” Many different magnetic confinement concepts were explored during the early

1950s. Although researchers were careful to note

that practical applications lay at least 10 to 20

years in the future, the devices being studied

were thought to be capable of leading directly

to a commercial reactor.

In reality, however, very little was known about

the behavior of plasma in experiments and even

less about how it would act under the conditions

required for fusion reactors. Experimental results

were often ambiguous or misinterpreted, and the

theoretical understanding underlying the research

was not well established. By 1958—as people
Ch. I.—Executive Summary ● 9

Photo credtt: Los Alamos National Laboratory

Perhapsatron, built and operated in the 1950s at Los

Alamos Scientific Laboratory.

realized that harnessing magnetic fusion was going to be difficuIt and that national security considerations were less immediate—the research

was declassified. This action made widespread

international cooperation in fusion research possible, particularly since the countries involved

realized that the state of their research programs

was more or less equivalent.

With the optimism of the 1950s tempered, fusion researchers in the United States proceeded

at a steady pace throughout the 1960s. In 1968,

Soviet scientists announced a major breakthrough

in plasma confinement in a device called a “tokamak. ” After verifying Soviet results, the other

world fusion programs redirected their efforts

toward development of the tokamak.

1970s and 1980s

With the identification of the tokamak as a confinement concept likely to reach reactor-level

conditions, the U.S. fusion program grew rapidly.

Between 1972 and 1979, the fusion program’s

budget increased more than tenfold. This growth

was due in part to uncertainty in the early 1970s

concerning long-range energy supply; fusion

energy, with its potentially inexhaustible fuel supply, appeared to be an attractive alternative to

exhaustible resources such as oil and gas. In addition, the growth of the environmental movement

and increasing opposition to nuclear fission technology drew public support to fusion as an energy

technology that might prove more environmentally acceptable than other energy technologies.

The fusion program capitalized on this public

support; program leadership placed a high priority on developing a research plan that could

lead to a demonstration reactor. Planning began

for the Tokamak Fusion Test Reactor, a new experiment using D-T fuel that would reach

breakeven. By 1974, the funding increases necessary to pursue accelerated development of fusion were appropriated.

Program organization changed twice during the

1970s. In 1974, Congress abolished the AEC and

transferred its energy research programs to the

newly created Energy Research and Development Administration (ERDA). ERDA assumed

management of the AEC’s nuclear fission and fusion programs, as well as programs in solar and

renewable technologies, fossil fuels, and conservation. Three years later, President Carter incorporated the functions of ERDA into a new agency,

the Department of Energy (DOE).

Under DOE, the fusion program did not have

the same sense of urgency. Fusion could not mitigate the short-term oil and gas crisis facing the

United States. Furthermore, as a potentially inexhaustible energy source (along with solar energy

and the fission breeder reactor), fusion was not

expected to be needed until well into the next

century. Therefore, there appeared to be no compelling reasons to rapidly develop a fusion demonstration plant.

Nevertheless, the Magnetic Fusion Energy Engineering Act of 1980 urged acceleration of the national effort in magnetic fusion research, development, and demonstration activities. The act

recommended that funding levels for magnetic

fusion double (in constant dollars) within 7 years.

However, Congress did not appropriate these increases, and there was no follow-up. Actual appropriations in the 1980s have not grown at the

levels specified in the act; in fact, since 1977, they

have continued to drop in constant dollars.
10 ● Starpower: The U.S. and the International Quest for Fusion Energy

Photo credit: Princeton Plasrna Physics Laboratory

Model C Stellarator at Princeton Plasma Physics Laboratory. Designed and built in the late 1950s, the Model C was

converted into the United States’ first tokamak in 1970.

Despite constrained funding, the U.S. fusion

program has made significant advances in plasma

physics and fusion technology throughout the

1980s. However, DOE has had to adjust its longrange planning to the new fiscal situation. In

1985, it issued the Magnetic Fusion Program Plan

(MFPP), which states that the goal of the fusion

program is to establish the scientific and technological base required for fusion energy. This plan

explicitly recognizes that:

. . . although the need for and desirability of an

energy supply system based on the nuclear fusion principle have not diminished, there is less

urgency to develop such a system. ’

The plan emphasizes the importance of international collaboration if the United States is to establish fusion’s technological feasibility during the

early 21st century.

The history of U.S. magnetic confinement fusion research is discussed in chapter 3 of this

report.

 U.S. Department of Energy, Office of Energy Research, Magnetic

 Program P/an, DOE/ER-0214, February 1985, preface.
Ch. 1.—Executive Summary ● 11

FUSION SCIENCE

Great scientific progress has been made in the

field of fusion research over the past 35 years.

The fusion program appears to be within a few

years of demonstrating breakeven, an event that

will show an impressive degree of understanding and technical capability. Nevertheless, many

scientific and technological issues must be resolved before fusion reactors can be designed and

built. The principal scientific uncertainties involve

what happens to a plasma when it generates appreciable amounts of fusion power. Because no

existing devices can produce significant amounts

of power, this uncertainty currently cannot be explored. Simply reaching breakeven will not resolve the uncertainties, since the effects of internally generating fusion power will not be fully

AND TECHNOLOGY

realized under breakeven conditions. An ignited

plasma, or at least one with high energy gain,

must be studied. Issues to be resolved before fusion’s technological feasibility can be established

are discussed more fully in chapter 4.

Confinement Concepts

Besides the behavior of ignited plasmas, the

characteristics, advantages, and disadvantages of

various confinement concepts need further study.

Several different concepts, utilizing different configurations of magnetic fields and different methods of generating the fields, are being studied

(table l-l).

Photo credit: Princeton Plasma Physics Laboratory

The Tokamak Fusion Test Reactor at Princeton Plasma Physics Laboratory,

where breakeven experiments are scheduled for 1990.
12 ● Starpower The U.S. and the International Quest for Fusion Energy

Table 1-1.—Classification of Confinement Concepts

Well-developed Moderately developed Developing

knowledge base knowledge base knowledge base

Conventional Tokamak Advanced Tokamak Spheromak

Tandem Mirror Field-Reversed Configuration

Stellarator Dense Z-Pinch

Reversed-Field Pinch

SOURCE: Adapted from Argonne National Laboratory, Fusion Power Program, Technical Planning Activity: Final Report, commissioned by the U.S. Department of Energy, Office of Fusion Energy, ANL/FPP-87-1, 1987, p. 15.

At this stage of the research program, it is not

known which confinement concepts can form

the basis of an attractive fusion reactor. The tokamak is the most developed concept, and it has

attained plasma conditions closest to those required in a fusion reactor. Its experimental performance has been encouraging, and it provides

a standard for comparison to other concepts.

Studies of reactor-like plasmas must be done in

tokamaks because no other concept has yet demonstrated the potential to reach reactor conditions. Most fusion technology development takes

place in tokamaks as well. Although tokamak behavior has not yet been fully explained theoretically, it may well be possible to design reactorscale tokamaks on the basis of experimental performance in smaller tokamaks.

Research on alternatives to the tokamak continues because it is not clear that the tokamak

will result in the most attractive or acceptable fusion reactor. Moreover, research conducted on

different concepts provides important insights

into the fusion process. It remains to be seen

which alternate concepts will be able to reach

the level of performance already attained by the

tokamak, whether their relative strengths will be

preserved in the development process, and what

the costs of developing these concepts to reactor

scale will be. Nor is it known what the ultimate

capability of the tokamak concept will be.

Reactor Development

Just as an automobile is much more than spark

plugs and cylinders, a fusion reactor will contain

many systems besides those that heat and confine the plasma. Fusion’s overall feasibility will

depend on all of the “engineering details” that

support the fusion reaction, convert the power

released in the reaction into usable energy, and

ensure safe, environmentally acceptable operation. Developing and building these associated

systems and integrating them into a reactor will

require a technological development effort at

least as impressive as the scientific challenge of

understanding and confining fusion plasmas.

The overall fusion generating station (figure 1-4)

consists of a fusion power core, which contains

the systems that support and recover energy from

the fusion reaction, and the balance of p/ant,

which converts this energy to electricity. Fusion

reactor conceptual designs typically have balance

of plant systems similar to those found in existing electricity generating stations. However, fusion

technology may permit more advanced systems

to generate electricity in a manner that is qualitatively different from the methods in use today.

The fusion power core, shown schematically

in figure 1-5, is the heart of a fusion generating

station. The systems in the core create and maintain the plasma conditions required for fusion reactions to occur. These technologies confine the

plasma, heat and fuel it, remove wastes and impurities, and, in some cases, drive electric currents within the plasma. Other systems in the fusion power core recover heat from the fusion

reactions, breed fuel, and provide shielding. One

of the key requirements for many of these fusion

power core systems is the development of suitable materials that are resistant to the intense neutron radiation generated by the plasma. The environmental and safety aspects of fusion reactors

depend significantly on materials choice.

Future Plans and Facilities

Many additional experiments and facilities will

be required to investigate both scientific and technological aspects of fusion. Preliminary experiments that investigate the basic characteristics of
Ch. I.—Executive Summary c 13

In

Figure 1=4.—Systems in a Fusion Electric Generating Station

Rejected

heat

new confinement concepts can be done for a few

miIlion dollars or less. As concepts approach reactor capability, successively larger facilities are

required, with reactor-scale experiments costing

hundreds of millions of dollars each. Obviously,

the U.S. fusion program cannot afford to investigate every confinement concept at the reactor

scale; choices must be made on the basis of information gathered at earlier stages.

Additional facilities will be required to resolve

general issues not identified with specific confinement concepts. In particular, facilities will be

needed to address the scientific issues associated

with ignited plasmas. Many physical processes

associated with ignition can be studied in ignited

plasmas that only last for a few seconds; other

aspects, such as fueling and removal of reaction

products, will require a facility that can produce

ignited plasmas lasting hundreds of seconds.

Short- and long-burn ignition questions can be

studied either in a single device or in two separate devices. DOE has chosen to separate them,

Electric power

out to grid

and it has requested funds in its 1988 budget to

build a short-pulse ignition facility, called the

Compact Ignition Tokamak (CIT). Total costs for

this device are estimated at about $360 million.

CIT cannot satisfy the requirements for long

pulses, materials studies, or nuclear technology

testing. These needs could be addressed in separate facilities and later combined (except for materials testing) in a device that would integrate

all the systems for the first time. Alternatively,

many of these issues could be addressed and integrated simultaneously in a next-generation engineering test reactor. Satisfying a number of purposes simultaneously would complicate an

engineering test reactor’s design and could force

trade-offs between the different objectives. Moreover, it is likely that each additional requirement

will increase the price of the machine. Even so,

a general-purpose engineering test reactor would

presumably cost less than the combination of several single-purpose facilities and a subsequent

system-integration device.
14 ● Starpower: The U.S. and the International Quest for Fusion Energy

SOURCE: Modified from “The Engineering of Magnetic Fusion Reactors, ” by Robert W. Corm. Copyright © 1983 by Scientific

American, Inc. All rights reserved

DOE has not yet determined the features to be Thermonuclear Experimental Reactor (ITER), be

included in an engineering test reactor. It is com- undertaken.

mitted to investigating the possibility for international cooperation on the device; the U.S. Gov- Materials testing will require a dedicated deernment has proposed to the other major world vice even if a general-purpose engineering test

fusion programs that collaborative conceptual de- reactor is built. To complete lifetime irradiation

sign of such a device, called the International testing of reactor materials in a reasonable
Ch. I.—Executive Summary “ 75

Photo credit” GA Technologies

View inside vacuum vessel of D II I-D fusion device at GA Technologies, San Diego, CA.

The plasma is contained within this vessel.

amount of time, a source of fusion neutrons several times more intense than expected from a

commercial reactor is required. While an engineering test reactor wouId duplicate conditions

expected in a reactor, it would not be able to conduct accelerated materials tests at several times

the radiation levels to be found in a reactor.

Schedules and Budgets

A major fusion-communitywide study has identified the technical tasks and facilities required

to establish fusion’s technological feasibility and

enable a decision to be made early in the next

century to start the commercialization process,2

2

Argon ne National Laboratory, Fusion Power Program, 

 f’/anning Activity: Report, commissioned by DOE, Office

of Fusion Energy AN L/FPP-87-l, 1987,

The study estimated that the worldwide cost of

this research effort would be about $20 billion.

As mentioned earlier, developing fusion on this

schedule will require either substantially increased U.S. funding or wide-scale collaboration

among the world fusion programs.

The requirements and schedule for establishing fusion’s subsequent commercial feasibility are

more difficult to project, and they depend on factors other than fusion research funding. Conceivably, if the research program provides the information necessary to design and build a reactor

prototype, such a device could be started early

in the next century. After several years of construction and several more years of qualification

and operation, a base of operating experience

could be acquired that would be sufficient for the

design and construction of commercial devices.
16 ● Starpower: The us. and the Internatjonal Quest for Fusion Energy

If the regulatory and licensing process proceeded

concurrently, vendors and users could begin to

consider manufacture and sale of commercial fusion reactors sometime during the middle of the

first half of the next century. From that point, it

will take decades for fusion to penetrate energy

markets. Even under the most favorable circumstances, it does not appear likely that fusion will

be able to satisfy a significant fraction of the Nation’s electricity demand before the middle of

the 21st century.

This schedule for demonstrating technological

and commercial feasibility requires a number of

assumptions. Sufficient financial support or international coordination must be attained so that

the research needed to establish technological

feasibility can be completed early in the next century. Research must proceed without major difficulty and must lead to a decision to build a reactor prototype. The prototype must operate as

expected and prove convincingly that fusion is

both feasible and preferable to its alternatives.

Status of the World Programs

The United States, Western Europe, Japan, and

the Soviet Union all have major programs in fusion research that are at similar stages of development. Each program has built or is building a

major tokamak experiment. The U.S. Tokamak

Fusion Test Reactor and the European Community’s Joint European Torus are operating and are

ultimately intended to reach breakeven conditions with D-T fuel. Japan’s JT-60 tokamak, also

operational, will not use tritium fuel; it is intended

to generate a “breakeven-equivalent” plasma

using ordinary hydrogen and deuterium. The Soviet Union’s T-1 5 experiment is under construcPhoto credit: JET Joint Undertaking

The Joint European Torus, located in Abingdon,

United Kingdom.

tion. In addition to these major devices, each of

the programs operates several smaller fusion experiments that explore the tokamak and other

confinement concepts. Each program is also developing other aspects of fusion technology.

FUSION AS AN ENERGY PROGRAM

The long-term goal of the fusion program in the oriented towards producing fuel for fission reUnited States is to produce electricity. Fusion re- actors .)3

actors can also produce fuel for fission reactors

by irradiating suitable materials with neutrons, 3 A fusion reactor that produces fissionable fuel, or one that gen -

but this ability is not seen as fusion’s primary ap- erates part of its energy from fission reactions that are induced by

plication in the United States, Western Europe, fusion-generated neutrons, is called a reactor.

Although the applications and characteristics of hybrid reactors are or Japan. (The Soviet fusion effort does appear different from those of “pure fusion” reactors that do use or
Ch. I.—Executive Summary . 17

Photo credit; Japanese Atomic Energy Research Institule

The JT-60 tokamak, located in Naki-machi, Japan.

for fusion reactors that

been studied for a numresearch program is far

Hypothetical designs

produce electricity have

bet of years. Since the

from complete, however, current systems studies

are necessarily tentative. Although these studies

have been especially valuable in identifying improvements in fusion physics or technology that

appear to have the greatest potential for making

fusion reactors attractive and competitive, they

cannot provide a firm basis for assessing fusion’s

potential as a future energy source. Nevertheless,

the studies do provide a basis for projecting the

produce fissionable materials, there is little difference at present

I n the research requ I red to develop the two. Differences wil I arise

at subsequent stages of research and development.

This assessment focuses on pure fusion reactors; hybrid reactors

are discussed briefly in app. A of the full report,

possible characteristics of fusion reactors. These

projections will improve as additional knowledge

and understanding enable scientists and engineers to better model the reactor systems. Chapter 5 of this report discusses projected characteristics of fusion reactors, along with the factors

that will determine the degree to which fusion

is accepted in the energy marketplace.

Safety

If fusion development is successful, it maybe

possible to ensure that accidents due to malfunctions, operator error, or natural disasters

could not result in immediate public fatalities.

This safety would depend on passive systems or

on materials properties, rather than on active systems that could fail or be overridden. A number
18 . Starpower: The U.S. and the International Quest for Fusion Energy

of attributes of the fusion process should make

safety assurance easier for fusion reactors than

for fission reactors:

●

●

●

●

Fusion reactions cannot run away. Fuel will

be continuously injected, and the amount

contained inside the reactor chamber will

only operate the reactor for a short period

of time. Energy stored in the plasma at any

given time can be dissipated by the vacuum

chamber in which the fusion reactions take

place.

With appropriate choice of materials, the

amount of heat produced by the decay of

radioactive materials in the reactor after the

reactor has been shut down should be less

for fusion reactors than for fission reactors.

Fusion reactors should therefore require simpler post-shutdown or emergency cooling

systems, if any such systems are required at

all.

The radioactive inventory of a fusion reactor

—in terms of both the total amount present

in the reactor and the fraction that would be

likely to be released in an accident–should

be smaller than that of a fission reactor. Fusion will not generate long-lived wastes such

as those produced by fission reactors. Except

for tritium gas, the radioactive substances

present in fusion reactors will generally be

bound as metallic structural elements.

in the event of accidental release, fusion reactors should not contain radioactive elements

—except tritium —that would tend to be absorbed in biological systems. Tritium is an

inherent potential hazard, but the risk it

poses is much smaller than that of the gaseous or volatile radioactive byproducts present in fission reactors, Active tritium inventories in current fusion reactor designs are

small enough that even their complete release should not produce any prompt fatalities off-site. Moreover, fusion reactors operating on advanced fuel cycles would not

need tritium.

This discussion does not imply that fission reactors are unsafe. Indeed, efforts are underway

to develop fission reactors whose safety does not

depend on active safety systems. However, the

potentially hazardous materials in fission reactors

include fuels and byproducts that are inherent

to the technology. While the tritium fuel required

by a D-T fusion reactor is a potential hazard, the

byproducts of fusion are not in themselves hazardous, Since there is much greater freedom to

choose materials that minimize safety hazards for

fusion reactors than there is in fission reactor design, a higher degree of safety assurance should

be attainable with fusion.

Environmental Characteristics

Fusion reactors will not be free of radioactive

wastes, although the wastes that they produce

should be easier to dispose of than fission

wastes. Fusion reactors will not generate the longIived and highly radioactive wastes contained in

the spent fuel rods of fission reactors. Fusion

wastes may have a greater physical volume than

fission wastes, but they should be substantially

less radioactive and orders of magnitude less

harmful. The amount of radioactive waste anticipated from different fusion designs ranges over

several orders of magnitude because it depends

on the choice of materials with which the reactor

is made. Special materials that do not generate

intense or long-lived radioactive wastes may be

developed that would make it possible to substantially reduce the radioactive waste produced

by a fusion reactor.

Nuclear Proliferation Potential

The ability of a fusion reactor to breed fissionable fuel could increase the risk of nuclear

proliferation. Proliferation concerns relate to the

possibility of constructing fission-based or atomic

weapons. Although fusion reactors contain tritium,

a material that could be used in principle to make

thermonuclear weapons such as the hydrogen

bomb, such weapons cannot be built by parties

who do not already possess fission weapons.

A reactor deriving all its energy from fusion and

producing only electricity would not contain materials usable in fission-based nuclear weapons,

and it would be impossible to produce such materials by manipulating the reactor’s normal fuel

cycle. However, material usable in fission weapons could be produced by placing other materi-
Ch. I.—Executive Summary “ 1 9

als inside the reactor and irradiating them with

fusion neutrons. This procedure, in effect, would

convert a pure fusion reactor into a fission/fusion

hybrid reactor (see note 3, above). If such modifications to the reactor structure were easily detected or were extremely difficult and expensive,

pure fusion reactors would be easier to safeguard

against surreptitious production of nuclear weapons material than existing fission reactors, and fusion reactors would therefore pose less of a

proliferation risk.

Resource Supplies

Shortage of fuels will not constrain fusion’s

prospects for the foreseeable future. Enough

deuterium is contained in the earth’s waters to

satisfy energy needs through fusion for billions

of years at present consumption rates. Domestic lithium supplies should offer thousands of

years worth of fuel, with vastly greater amounts

of potentially recoverable lithium contained in

the oceans.

Materials required to build fusion reactors may

pose more of a constraint on fusion’s development than fuel supply, but at this stage of research

it is impossible to determine what materials will

eventually be developed and selected for fusion

reactor construction. No particular materials

other than the fuels appear at present to be indispensable for fusion reactors.

cost

It is currently impossible to determine

whether a fusion reactor, once developed, will

be economically competitive with other energy

technologies. The competitiveness of fusion

power will depend not only on successful completion of the remaining research program but

also on additional factors that are impossible to

predict—e.g., plant licensability, construction

time, and reliability, not to mention factors less

directly related to fusion technology such as interest rates. Fusion’s competitiveness will also depend on technical progress made with other

energy technologies.

Fusion’s Energy Context

The factors that influence how successfully

fusion technology will compete against other

energy technologies include how well its characteristics meet the requirements of potential customers (most likely electric utilities) and how well

fusion compares to alternate electricity-generating

technologies. A more detailed look at these factors

●

●

●

makes a number of points clear:

The overall size and composition of electricity demand, by itself, should neither require nor eliminate fusion as a supply option. Supplies of both coal and uranium

appear adequate at reasonable prices to

meet high future demand in the absence of

fusion. 4 It will be overall economics and

acceptability, rather than total demand or

fuel availability, which will determine the

mix of energy technologies.

It is unlikely that any one technology will

take over the electricity supply market, barring major difficulties with the others.

Potential problems with currently foreseen

future sources of electricity provide incentives to develop alternate energy technologies and/or substantially improve the efficiency of energy use. Combustion of coal

releases carbon dioxide, whose accumulation in the atmosphere may affect world climate; this problem may make increased reliance on coal undesirable. Safety, nuclear

waste, or nuclear proliferation concerns may

continue to impair expansion of the nuclear

fission option. The urgency for developing

fusion, therefore, depends on assumptions

of the likelihood that existing energy technologies will prove undesirable in the

future.

4Coal supplies are adequate to provide power for centuries at

current rates of use. Uranium supplies should be available at a reasonable price until well into the next century without requiring either breeder reactors or reprocessing. Advanced, more efficient fission reactors could delay the need for breeders or reprocessing

still further. With the use of breeders, uranium depos}ts become

adequate for centuries.
20 ● Starpower: The U.S. and the International Quest for Fusion Energy

● There is little to be gained and a great deal supply, that alternative must be preferable

to be lost if fusion is prematurely intro- in order to be accepted, It would be unwise

duced without attaining its potential eco- to emphasize one fusion feature—economics

nomic, environmental, and safety capabil- or safety or environmental advantages—over

ities. Even in a situation where problems the others before we know which aspect will

with other energy technologies urgently call be most important for fusion’s eventual

for development of an alternative source of acceptance.

FUSION AS A RESEARCH PROGRAM

The ultimate objective of fusion research is to

produce a commercially viable energy source.

Yet, because the research program is exploring

new realms of science and technology, it also provides near-term, non-energy benefits. These benefits fall in four major categories.

Near-Term Benefits

1. Development of Plasma Physics

Plasma physics as a branch of science began

in the 1950s, driven by the needs of scientists

working on controlled thermonuclear fusion and,

later, by the needs of space science and expiration. The field of plasma physics has developed

rapidly and has synthesized many areas of physics

previously considered distinct disciplines. Magnetic fusion research funding is crucial to the continuation of plasma physics research; over half

of all Federal plasma physics research is funded

by the magnetic fusion program.

2. Educating Scientists

Educating scientists and engineers is one of the

most widely acknowledged benefits of the fusion

program. Over the last decade, DOE’s magnetic

fusion energy program has financed the education of most of the plasma physicists produced

in the United States. DOE, through its magnetic

fusion program, directly supports university fusion programs and provides 37 fusion fellowships

annually to qualified doctoral students. Training

in plasma physics enables these scientists to contribute to defense applications, space and astrophysical plasma physics, materials science, applied mathematics, computer science, and other

fields.

3. Advancing Science and Technology

Many high-technology research and development (R&D) programs produce secondary benefits or “spin -offs.” Over the years, the magnetic

fusion energy program has contributed to a variety of spin-off technologies with wide-ranging

applications in other fields. Among them are superconducting magnet technology, high-quality

vacuums, high-temperature materials, highfrequency and high-power radiofrequency waves,

electronics, diagnostics and tools for scientific

analysis, high-speed mainframe computers, and

particle beams. Although spin-offs may benefit

society, they are unanticipated results of research

and should not be viewed as a rationale for continuing or modifying high-technology research

programs. It is impossible to predict before-thefact which research investments will have the

greatest spin-off return.

4. Stature

The stature of the United States abroad benefits from conducting high-technology research.

The United States has been at the forefront of fusion R&D since the program began in the 1950s.

Maintaining a first-rate fusion program has placed

the United States in a strong bargaining position

when arranging international projects, has attracted top scientists from other fusion programs

to the United States, and has enhanced the reputation of the United States in scientific and technical programs other than magnetic fusion.
Ch. I.—Executive Summary ● 2 1

Near-Term Financial and

Personnel Needs

Financial Resources

The Federal R&D budget has grown steadily in

the 1980s. The bulk of this growth has been

driven by increases in defense spending, but nondefense R&D has also grown. The fraction of the

Federal R&D budget devoted to energy, however,

has been steadily declining during the 1980s. In

fiscal year 1987, energy R&D is estimated to account for less than 4 percent of the Federal R&D

budget.

virtually all fusion research is funded by the

Federal Government; due to fusion’s long-term,

high-risk nature, there is little private sector investment. Even though the fusion budget has

fallen, in constant dollars, to less than half of its

1977 peak, magnetic fusion has fared better than

many other energy programs. DOE’s energy programs in nuclear fission, fossil fuels, conservation,

and renewable energy technologies have lost

proportionately more of their Federal support because it is believed that private sector financing

is more appropriate in these cases. Figure 1-6

shows the budgets of DOE’s larger energy R&D

programs during the 1980s.

Personnel Resources

The fusion program currently supports approximately 850 scientists, 700 engineers, and 770

technicians. s These researchers work primarily

at national laboratories and in university and college fusion programs. According to estimates by

DOE, the number of Ph.D. staff positions in the

fusion program has declined by almost 20 percent since 1983. Most of the fusion researchers

who have left the fusion program have found

work in other research programs within DOE and

the Department of Defense. Many former fusion

researchers, for example, are working on Strategic Defense Initiative projects,

SThOnlas G. Finn, Department of Energy, Office of Fusion Energy,

letter to the Office of Technology Assessment, Mar. 12, 1987. The

number of technicians represents only full-time staff associated with

experiments; shop people and administrative staff are not included.

Figures for scientists and engineers include university professors

and post-doctoral appointments; graduate student employees are

not included.

Participation in the Magnetic

Fusion Program

The Department of Energy’s Office of Fusion

Energy (OFE) conducts research through three

different groups: national laboratories, colleges

and universities, and private industry. Each of

these groups has different characteristics, and

each plays a unique role in the fusion program.

National Laboratories

It is estimated that national laboratories will

conduct over 70 percent of the magnetic fusion

R&D effort in fiscal year 1987. According to DOE,

the laboratories are “a unique tool that the United

States has available to carry on the kind of large

science that is required to address certain problems in fusion.” G Four laboratories conduct the

bulk of the Nation’s fusion research: Lawrence

Livermore National Laboratory in Livermore, CA;

Los Alamos National Laboratory in Los Alamos,

NM; Oak Ridge National Laboratory in Oak Ridge,

TN; and Princeton Plasma Physics Laboratory in

Princeton, NJ.

Universities and Colleges

Within the fusion program, universities and colleges provide education and training and historically have been a major source of innovative

ideas as well as scientific and technical advances.

It is estimated that the university and college programs will receive about 11 percent of the Federal fusion budget directly in fiscal year 1987. I n

addition, they will probably receive another 2 or

3 percent through the national laboratories.

Recent budget cuts have seriously affected

university and college fusion programs. Over 80

percent of these programs have budgets of less

than $1 million, and there are no other sources

of Federal funding for fusion research to replace

DOE appropriations. Since 1983, two-thirds of the

university and college fusion programs have reduced or eliminated their programs. The University Fusion Associates, an informal grouping of

individual researchers from universities and colbJOhn F. clarke, Director of the DOE Office of Fusion Energy,

“Planning for the Future, ” Journal of Fusion Energy, vol. 4, Nos.

2/3, June 1985, p. 202.
22 ● Starpower: The U.S. and the international Quest for Fusion Energy

Figure l-6.—Annual Appropriations of DOE Civilian R&D Programs (in currant dollars)

3.2

3.0

Ieges, anticipates that as many as half of the institutions represented by its members will eliminate their fusion programs between 1986 and

1989 if the university fusion budgets are not maintained. DOE, however, disputes this claim and

projects constant budgets (corrected for inflation)

for the university programs.

Private Industry

private industry can take a variety of different

roles in fusion research, depending on its level

of interest in the program and the status of fusion development. At the lowest level, industry

can serve as an advisor to DOE and the national

laboratories. As the research approaches the engineering stage, industry can begin to participate

directly by supplying components or contracting

with DOE. Ultimately, it is anticipated that industry will sponsor research and development

activities.

To date, industry and utility involvement in

magnetic fusion R&D has been advisory, with

limited cases of direct participation. This is due

largely to fusion’s long time horizon and the lack

of predictable, easily commercializable “spin-off”

technologies. Most current industrial participation is facilitated through subcontracts from national laboratories.
Ch. I.—Executive Summary ● 2 3

Photo credit: Plasma Fusion Center, MIT

The Alcator C tokamak at the Massachusetts Institute of Technology.

The transition of responsibility for fusion research and development from government to industry is a significant hurdle to be cleared before

fusion can be commercialized. Current DOE policy calls for any demonstration fusion reactor to

be built and operated by the private sector. Industries and utilities, on the other hand, may be

unwilling to risk a major investment in a new and

unproven technology.

There is considerable controversy over the

appropriate time for the private sector to become more involved in the research program.

Some argue that the willingness of industry to invest in fusion technology should not be used as

a criterion for determining its appropriate degree

of involvement. They maintain that early involvement of industry in fusion research is necessary

to ensure that the technology will be attractive

to its eventual users and marketable by the private sector. Others counter that, given present

and foreseeable future research budgets, there

are not enough opportunities for the private sector to develop and maintain a standing capability in fusion. These individuals believe that industry’s limited participation in fusion research in the

near-term will not preclude its eventual role in

demonstration and commercialization.

Chapter 6 of this report describes characteristics of fusion as a near-term research program—its

near-term benefits, its financial and personnel

needs, and its principal participants.
24 ● Starpower: The U.S.. and the International Quest for Fusion Energy

Photo credit: GA Technologies

The Ohmically Heated Toroidal Experiment at GA Technologies, Inc., which is the only major fusion experiment constructed

and operated largely with private funds.

FUSION AS AN INTERNATIONAL PROGRAM

The field of magnetic fusion research has a 30-

year history of international cooperation. The

leaders of the U.S. fusion community continue

to support cooperation, as does DOE. In the past,

the United States cooperated internationally in

a variety of exchanges that have produced useful information without seriously jeopardizing the

autonomy of the domestic fusion program. In recent years, in response to budgetary constraints

and the technical and scientific benefits of cooperation, DOE has begun cooperating more intensively in fusion, and the major fusion programs

have become more interdependent. For the future, DOE proposes undertaking cooperative projects that will require the participating fusion programs to become significantly interdependent:

indeed, DOE now sees more extensive international cooperation as a financial necessity.

Opportunities for Increased

Collaboration

Cooperation among the major world fusion

programs can be expected to continue at its current level, at the least, as long as each of the major fusion programs maintains a level of effort

sufficient to make it an attractive partner to the

others. In the future, it is also possible that a substantially expanded degree of collaboration may

take place. Such collaboration may take two forms:
Ch. I.—Executive Summary s 25

joint construction and operation of major facilities on a scale not yet attempted among the four

programs, and substantial additional joint planning among the world programs to minimize redundant research and to maximize the transfer of information and expertise among the programs.

Those who favor increased levels of collaboration believe that there will be important opportunities over the next decade. At the same time

that similarities in the status and goals of the major international fusion programs provide a technical basis for expanded cooperation, the comparable levels of achievement ensure that each

program can contribute to and benefit from collaboration. Moreover, commercial applications

of fusion technology are sufficiently far off that

competitive concerns should be minimal. Since

the programs may not remain comparable over

the long term, these pro-collaboration observers

maintain that the timing may not be as advantageous for collaboration in the future as it is now.

In particular, they worry that if recent funding

trends continue, the U.S. fusion program may fall

behind the other programs and might no longer

be viewed as a desirable partner.

Benefits and Liabilities

of Cooperation

International collaboration introduces a number of potential benefits and liabilities to the participants. Observers will weigh these features

differently, arriving at different conclusions about

the value of collaboration:

● Knowledge Sharing. All forms of cooperation involve sharing knowledge. Researchers can take advantage of one another’s experience, greatly aiding their own progress.

Some observers, however, are concerned

that collaboration could lead to exchange of

information that has adverse implications for

national security or technological competitiveness.

● Cost Sharing. Cooperation can save the partners money by spreading out the costs of experiments among the participants and avoiding duplication of effort. Some additional

costs may be added as a result of increased

administrative complexity, but barring un-

●

●

●

usual circumstances each partner should

spend less through collaboration than it

would to duplicate the research by itself.

Risk Sharing. The financial and programmatic costs of a collaborative project are

spread among a number of participants, minimizing the exposure of any one of them in

the event of failure. On the other hand,

through collaboration, each party opens itself up to the risk that withdrawal of any of

the other partners may jeopardize the success of the entire project. A partner may also

become dependent on others for the continuation of its own program. Finally, some

observers feel that the absence of competition and duplication among experimental facilities may increase the risk of technical

failure.

Diplomatic and Political Implications. Collaboration can be diplomatically motivated,

because it may improve relations and increase familiarity between the partners.

Some analysts welcome this additional aspect of collaboration; others fear that diplomatic motivations may override technical

ones, causing a project to be undertaken that

might not be judged attractive on its technical merits alone.

Domestic Implications. If the domestic program is neglected in order to support the collaboration, both the ability of the partner to

collaborate and the value of collaboration

to that partner may be compromised. Even

if the domestic program is not damaged, it

will be influenced by participation in collaboration. Becoming dependent on collaboration lessens the flexibility of the partners

to change research direction and emphasis.

On the other hand, collaboration can stabilize domestic efforts; the additional commitment given to a collaborative effort makes

it more difficult for domestic contributions

to that effort to be cut back.

Obstacles to International

Cooperation

The process of organizing and executing largescale collaboration presents challenges that must

be overcome by each of the partners. Among the
26 ● Starpower: The U.S. and the International Quest for Fusion Energy

challenges will be siting the facility, resolving the

technology transfer concerns of the parties and

making them compatible with an open exchange

of research results, resolving technical differences

among the parties, and overcoming a variety of

administrative obstacles including different institutional frameworks, different budget cycles,

different legal systems, and personnel needs.

Negotiating and executing workable agreements for international collaboration will undoubtedly be a difficult and time-consuming

process. Legal and institutional frameworks must

be devised that address the issues in a manner

acceptable to participants in the project.

The International Thermonuclear

Experimental Reactor

Currently, most of the effort in international collaboration is focused on a proposal to develop

a conceptual design for an international engineering test reactor, called the International Thermonuclear Experimental Reactor (ITER). Estimates indicate that building an engineering test reactor

will cost well over $1 billion and possibly several times this amount, which is far more than

the U.S. fusion program has spent on any one

facility in the past and is too expensive for the

United States to undertake alone without substantial increases in fusion funding. Therefore, DOE

is involved in discussions with the other worldwide fusion programs to jointly design, construct,

and operate ITER.

At this stage, only the conceptual design of ITER

is being considered by the potential collaborators; the U.S. Government recently issued a proposal to begin a joint planning activity on a conceptual design for the experiment, along with

supporting R&D. It is anticipated that the conceptual design phase of ITER will occur between

1988 and 1990 at a total estimated cost ranging

from $150 million to $200 million. The U.S. cost

of the undertaking is projected to be between $15

million and $20 million annually over the 3-year

program.

Since the U.S. Government proposal addresses

only the conceptual design phase of ITER, it

makes no commitment to future construction of

a collaborative experiment. Therefore, current

negotiations will not address the obstacles to international collaboration that would arise if and

when the decision were made to jointly construct

and operate the device. At the completion of the

conceptual design phase, interested parties

would be in a position to begin negotiations on

whether or not to proceed with construction. The

existence of a conceptual design would make it

easier to resolve many of the questions that would

arise should a subsequent decision be made to

build and operate ITER. In particular, it should

be possible to analyze concerns about technology transfer specificalIy and determine their implications for national security or industrial competitiveness.

International cooperation on the scale required for ITER is unprecedented for the United

States. Reaching agreement within the U.S. Government to initiate and maintain support for ITER

over the lifetime of the project will probably require a presidential decision. Even that, by itself,

is insufficient to guarantee the viability of a project

involving all branches of the U.S. Government

and extending over several presidential administrations.

At this time, DOE considers international collaboration on the scale of ITER to be crucial.

Given the seriousness of the obstacles, however,

it is possible that such collaboration may not occur, In the event that no major collaboration

takes place, either the U.S. fusion program will

have to be funded at a higher level or its schedule will have to be slowed down and revised.

International issues are discussed in chapter

7 of this report.
Chapter 2

Introduction and Overview
Chapter 2

Introduction and Overview

FUSION POWER

To geologists and physicists at the turn of the

century, the term “energy problem” referred not

to finding sources of energy for society, but to

identifying the one used by the sun. Most physicists believed that the source of the sun’s energy

was heat released as the sun slowly shrank under its own gravity, a process that would burn

out no more than 20 million years after the sun

was formed. Geologists, however, argued that

geological and fossil evidence showed that the

earth-assumed to be no older than the sun—

was in fact many times more than 20 million years

old.

Although many hypotheses were developed to

reconcile the two positions, it was not until 1938

that one explanation received virtually instantaneous and universal acclaim: the sun’s “energy

problem” was solved when nuclear fusion was

identified as its energy source. Through fusion,

the sun has been able to shine for nearly 5 billion years using only about half of its original fuel.

Nuclear fusion is the process by which the

nuclei—or central cores—of two atoms combine

or fuse together. The total mass of the final products is slightly less than the total mass of the original nuclei, and the difference—less than 1 percent of the original mass—is released as energy.

Nuclear fusion, in a sense, is the opposite of nuclear fission, the process utilized in existing nuclear powerplants. In a fission reaction, energy

is released when a heavy nuclei splits into smaller

pieces whose total mass is slightly less than that

of the original nucleus.

Nuclear fusion may be applicable to the energy

needs of humans. If the fusion process can be

utilized economically, it has the potential to provide society with an essentially unlimited source

of electricity. It may also offer significant environmental and safety advantages over other energy

technologies, characteristics that are particularly

appealing in a world where no energy technology is perfect. Since the 1950s, the potential payoff of fusion energy has motivated a worldwide

research effort.

The previous decades of research have shown

that fusion energy is extremely difficult to produce. Experiments planned for the next few years

shouId be able to assess fusion’s scientific feasibility as an energy source, but several decades

of additional research and development, and billions of additional dollars, will be needed to see

whether a marketable fusion reactor can be developed. Researchers in the United States, Western Europe, Japan, and the Soviet Union generally agree on the technical tasks yet to be done

to evaluate fusion’s potential. Policy makers in

these nations must now decide if, when, and how

to allocate the resources necessary to accomplish

these tasks.

The Allure

In the future, fusion power could bean attractive source of energy because it might offer a

combination of benefits unmatched by other

fuels. Compared to other energy technologies,

fusion could be:

Unlimited. A form of hydrogen found naturally in water is a potential fusion fuel, and

every gallon of water on earth contains the

fusion energy equivalent of 300 gallons of

gasoline.

Clean. Using fusion reactions to generate

power may be significantly cleaner than either fossil fuels or nuclear fission. Fusion,

unlike coal combustion, does not produce

carbon dioxide whose accumulation in the

atmosphere may affect world climate. Moreover, fusion will not contribute to acid rain

or other potential environmental damage

associated with fossiI fuels. Although fusion

reactors themselves will become radioactive,

the products of the fusion reaction are not

radioactive. With appropriate choice of struc29
—

30 . Starpower: The U.S. and the International Quest for Fusion Energy

●

tural materials, fusion reactors will produce

far less radioactive waste than fission reactors.

Safe. It may be possible to design fusion reactors in which “safe operation is assured by

physical properties, rather than by active

safety systems that might fail due to malfunction, operator error, or natural disaster.

Substantial further scientific and technological development is required to see whether these benefits can be attained,

Establishing Fusion’s Feasibility

Two requirements must be met before fusion

can be an attractive source of energy. First, fusion’s technological feasibility must be demonstrated by establishing the scientific and engineering understanding necessary to build an operating

fusion reactor. Second, fusion’s commercial feasibility must be demonstrated.

Technological feasibility is usually considered

in two stages: scientific feasibility and engineering feasibility. Scientific feasibility requires generating a fusion reaction that produces at least

as much energy as must be input into the plasma

to maintain the reaction. This milestone, called

breakeven, has not yet been reached, but it is

expected that breakeven will be accomplished

in existing machines by 1990.

Simply breaking even, however, does not show

that fusion can serve as a useful source of energy.

in addition, a fusion reaction must be created that

has high energy gain, producing an energy output many times higher than its energy input. No

existing experiment has the capability to produce

such a reaction, a task that is more significant and

more difficult to achieve than breakeven. However, the Department of Energy (DOE) has requested funds in its fiscal year 1988 budget to begin construction of an experiment to generate a

reaction with such high-gain that it should become self-sustaining, or ignited. At ignition, reactions will generate enough power to sustain the

fusion process even after external heating power

has been shut off.

After high gain or ignition has shown fusion’s

scientific feasibility, its engineering feasibility must

be demonstrated. This accomplishment will entail developing future reactor systems, subsystems,

and components that can function reliably under reactor operating conditions. Demonstrating

engineering feasibility will require an extensive

amount of research and development, and it will

be a technical achievement at least as impressive

as the scientific accomplishment of harnessing

controlled fusion reactions.

Although scientific feasibility and engineering

feasibility involve different issues, fusion science

and fusion engineering are interdependent: advancing scientific understanding of the fusion

process requires improved technological capabilities in experimental facilities, just as solving

the engineering problems posed by fusion reactor

design requires additional basic understanding in

a number of areas. Demonstrating both the scientific and engineering feasibility of fusion power

requires advances to be made in basic scientific

understanding as well as in technological capability.

The goal of fusion research is to establish fusion’s technological feasibility in a manner that

makes commercial feasibility likely. If and when

it becomes clear that generating electricity in a

fusion reactor is possible, such a reactor must

prove socially and environmentally acceptable

and economically attractive compared to its alternatives. Although dependent on the technical results of fusion research, fusion’s commercial feasibility also involves factors unrelated to the

technology itself, such as the status of other

energy technologies and the regulatory and licensing structure. Commercial feasibility ultimately will be determined by individuals and institutions that are not involved directly in fusion

research.

The Fusion Reaction

Only light elements can release energy through

fusion. While many different fusion reactions take

place in the stars, the one that can be used most

easily to generate power on earth involves hydrogen (H), the lightest element. Three forms, or isotopes, of hydrogen exist: protium, which is usually referred to simply as hydrogen, deuterium

(D), and tritium (T). The nuclei of these isotopes
Ch. 2.—Introduction and Overview “ 31

consist of a single proton and zero, one, or two

neutrons, respectively. Over 99.98 percent of all

hydrogen found in nature is the protium isotope.

Less than 0.02 percent (one part in 6,700) is composed of deuterium. Tritium is radioactive, with

a half-life of 121/4 years;1 it is practically nonexistent in nature, but it can be manufactured.2

The easiest fusion reaction to initiate combines

deuterium and tritium to form helium and a free

neutron, as shown in figure 2-1; a fission reaction

is also shown for comparison. The fusion reaction

shown—called a D-T reaction—liberates 17.6 million electron volts3 of energy. By way of comparison, burning a single atom of carbon (the combustible material in coal) releases only about 4

electron volts. Therefore, a single D-T fusion reaction is over 4 million times more energetic.

Four-fifths of the energy released in a D-T fusion reaction is carried off by the neutron as kinetic energy. I n a fusion reactor, it is anticipated

that neutrons would be captured in the material

surrounding the reaction chamber, where their

kinetic energy would be converted into heat.

One-fifth of the reaction energy, carried off by

the helium nucleus, would remain inside the reaction chamber, heating up the fuel and making

additional reactions possible.

The primary application of fusion will probably

be for electric power generation, using heat from

the fusion reaction to boil water to drive a steam

turbine that generates electricity. Advanced systems for converting fusion energy more directly

into electricity may also be possible. Other applications of fusion might use the neutrons themselves for various purposes, rather than just extracting their energy. It is also possible that, as

fusion development progresses, additional uses

of the technology might be found. The potential

I Radioactive materials decay over time as the nuclei of radioactive

atoms emit radiation and transform into other nuclei. The decay

rate is measured by the substance’s ha/f-/ife, which is the time required for half of the nuclei to be transformed.

2

Trace amounts of tritium are continually produced by cosmic

rays in the upper atmosphere. Most of the tritium now in the environment, however, was produced by atmospheric nuclear weapons tests In the 1950s.

30ne electron volt (eV) is the energy that a single electron can

pick up from a 1 -volt battery. It is equal to 1.6 X 10-’9 joules, 1.52

x 10”22 Btu, or 4.45 x 10-26 kilowatt-hours. One thousand electron volts is called a kiloelectron volt, or keV.

characteristics of fusion reactors used to produce

electricity are discussed in chapter 5; other possible applications of fusion are discussed in appendix A.

The D-T reaction is not the only one that can

generate fusion energy. One deuterium nucleus

can fuse with another in a D-D reaction. It is also

possible to use other light elements besides hydrogen as fuel. However, it is much harder to initiate fusion reactions with fuels other than deuterium and tritium, and many of these alternate

fuels produce less power for a given amount of

fuel than the D-T reaction does. Reactors using

alternate fuels would be more difficult to design

and build than D-T reactors producing the same

amount of energy. On the other hand, these alternate reactions may not require tritium production and/or may not generate as many neutrons

as the D-T reaction. Both tritium production and

neutron generation increase the amount of radioactive material contained in a reactor, a situation

that complicates the reactor’s design and can

raise environmental and safety issues.

Requirements for Fusion Reactions

Fusion reactions can only occur when the requirements of temperature, confinement time,

and density are simultaneously met. The minimum temperatures, confinement times, and densities needed to produce fusion power have been

known for decades. Achieving these conditions

in experiments, however, has proven extremely

difficult.

Temperature

Because the nuclei that must fuse have the

same electrical charge, they must be heated to

extremely high temperatures to overcome their

natural repulsion. Temperatures on the order of

100 million degrees Celsius (C) are required. No

matter exists in solid form at these temperatures;

individual atoms are broken down—ionized—

into their constituent electrons and nuclei. With

their outside electrons missing, the nuclei have

a positive electric charge and are called ions.

Matter in this state is called plasrna (figure 2-

2). Plasma is considered a fourth state of matter
32 . Starpower: The U.S. and the International Quest for Fusion Energy

Figure 2-1 .—The D-T Fusion Reaction and a Fission Reaction

● Proton

Key:

o Neutron

MeV: million electron volts

SOURCE: Adapted from Princeton Plasma Physics Laboratory, Information Bulletin NT-1: Fusion Power, 1984, p. 2 (fusion); Office of Technology Assessment (fission), 1987,
Ch. 2.—Introduction and Overview “ 33

Figure 2-2.— Gas and Plasma

because it has properties unlike solids, liquids,

or gases. Fusion research, critically dependent on

understanding plasmas, has led to the development of a new field of science called plasrna

physics.

The temperature of a plasma is a measure of

the average energy of the plasma particles and

is usually expressed in units of electron volts. A

plasma temperature of 1 electron volt, which is

about 11 ,600° C, corresponds roughly to each

particle in the plasma having an average energy

of 1 electron volt. In a plasma, the ions and the

electrons can have different temperatures; ion

temperature is most important and must exceed

about 10,000 electron volts for enough of the ions

to overcome their mutual repulsion to produce

appreciable amounts of fusion power.

Confinement Time

The goal of fusion research is not only to create a hot plasma but also to keep it hot long

enough to produce fusion power. [t is not sufficient simply to heat the fuel, because any substance that is hotter than its surroundings will cool

off. The rate at which the substance cools depends on its physical characteristics, its surroundings, and the temperature difference between the

two. The ability of a plasma to stay hot is represented by its confinement time, which is a measure of the time it would take to cool down to a

certain fraction of its initial temperature if no additional heat were added.

With an insufficient confinement time, it is impossible to reach breakeven or ignition. Even if

the plasma is heated hot enough for fusion reactions to start, heat would be lost faster than it

would be generated in those reactions, and the

reactions would not produce any net power.

Confinement times on the order of one second

are generally considered necessary for an ignited

plasma.

Density

The exact confinement time requirement depends on plasma density. The fusion reaction

rate, and therefore the amount of fusion power

produced by the plasma, goes down rapidly as

density drops. A plasma that is not dense enough

will not be able to generate power even if it is

very hot and retains its heat very well. The density required to reach breakeven or ignition increases as confinement time decreases. The prod-
—

34 . Starpower: The U.S. and the International Quest for Fusion Energy

uct of density and confinement time (called the

Lawson parameter) must exceed a minimum

threshold in order for a fusion plasma to ignite.4

Confining Fusion Plasmas

A fusion plasma cannot be contained in an ordinary vessel no matter how hot the vessel is

heated, because the plasma will be instantly

cooled far below the minimum temperature required for fusion whenever it comes into contact

with the vessel walls. There are three primary

ways to hold a plasma that avoid this obstacle.

Only one of these–magnetic confinement-is

discussed to any appreciable extent in this report.

Magnetic Confinement

Magnetic confinement relies on the fact that

because individual particles in a plasma are electrically charged, their motion is strongly affected

4

The minimum threshold for ignition, as defined by the Lawson

parameter, is 3 X 10~4 second-particles per cubic centimeter. This

means that a plasma with a density of 3 X 10’4 particles per cubic

centimeter must be confined for one second in order to ignite. As

mentioned above, if the density were increased to 3 x 1015 particles per cubic centimeter, then the confinement time requirement

would decrease to one-tenth (O. 1 ) of a second.

by magnetic fields. A charged particle moving in

a magnetic field will be bent at right angles to

both the direction of the field and its direction

of motion, with the result that the energetic particles making up a fusion plasma will trace spiral

orbits around magnetic field lines (figure 2-3).

Magnetically confined plasmas will tend to flow

along field lines but not across them, and a suitable configuration of magnetic fields can therefore confine a plasma. Many different kinds of

magnetic-confinement configurations are u rider

investigation, as described in chapter 4. In this

report, the word fusion refers to magnetic confinement fusion unless specifically noted otherwise.

Gravitational Confinement

A sufficiently large plasma can produce fusion

power while holding itself together with its own

gravitational field. This process, called gravitational confinement, permits fusion to take place

in the sun and other stars. It is impossible, however, to utilize gravitational confinement for fusion processes on earth. Even the planet Jupiter,

which is over 300 times more massive than earth,

does not have sufficient mass to produce gravitationally confined fusion.

SOURCE: Princeton Plasma Physics Laboratory, Information Bulletin NT-1: Fusion Power, 1984, p. 3,
Ch. 2.—Introduction and Overview “ 35

Inertial Confinement

In a hydrogen bomb, fusion fuel is heated and

compressed to such high densities that it need

be confined only for a very short time in order

to generate fusion power. The fuel’s own inertia

keeps it confined long enough for fusion reactions

to occur. A research effort is now underway to

study this inertial confinement process i n a controlled manner on a laboratory scale. This program has near-term military applications, due to

its close connection with weapons physics, and

may have longer term energy applications as well.

The energy applications of inertial confinement

fusion are generally considered less developed

than those of the magnetic confinement process.

Because of the direct links between this approach

and hydrogen bomb design, much of the research

in inertial confinement fusion is classified. The

inertial confinement approach is discussed in appendix B.

THE PURPOSE OF THIS STUDY

Increasing budgetary pressures, along with a

decreasing sense of urgency regarding energy

supply, have sharpened the competition for funding between one research program and another

and, perhaps more significantly, between energy

research programs and other components of the

Federal budget. At the same time, issues such as

the implications of increased fossil fuel usage on

the global climate and the long-term acceptability of nuclear power have raised serious concerns

about future energy supply.

In balancing the long-term potential of fusion

energy against shorter term, more immediate

pressures, the congressional committees with

jurisdiction over DOE’s magnetic fusion program

requested this study. In 1986, the House Committee on Science and Technology requested that

OTA review the magnetic fusion energy program,

citing that “. . . a number of factors have served

to decrease the sense of urgency with which the

DOE management and many members of the

Congress view the development of fusion power.”

Shortly afterward, the Senate Committee on

Energy and Natural Resources endorsed this request. These committees are faced with setting

policy for the fusion program, and they were interested in an independent analysis of the fusion

program as input to their budget authorization

deliberations.

in response, OTA undertook this assessment

of the magnetic fusion research and development

program in March 1986. The assessment examines the technical and scientific achievements and

objectives of the fusion program. It also analyzes

the program from three different, but related, perspectives:

1.

2.

3.

It considers the issues related to fusion’s role

as an energy research and development program, in particular those related to developing an attractive energy supply technology.

It analyzes the near-term, non-energy benefits of the fusion program and the financial

and personnel resources necessary to support the program.

It examines the increasing role of international collaboration in magnetic fusion research.

OTA’s assessment was carried out with the

assistance of a large number of experts reflecting different perspectives on the fusion program

–fusion scientists and engineers, nuclear engineers, environmental scientists, international relations experts, industry and utility executives,

consumer groups, economists, financial planners,

and energy policy analysts. As with all OTA studies,

an advisory panel representing these interests and

fields of expertise met periodically throughout the

course of the assessment to review and critique

interim products and proposals, to discuss fundamental issues affecting the analyses, and to review drafts of the report. Contractors and consultants also provided material in support of the

assessment.5

5Advlsory panel members, workshop participants, contractors,

and other contributors to this assessment are listed in the front of

this report.
36 . Starpower: The U.S. and the International Quest for Fusion Energy

Finally, OTA convened three workshops to

clarify important issues considered in the assessment and to review and expand upon contractors’ analysis. The first workshop dealt with general issues involved in fusion research. It focused

on the nature of the fusion research program, the

implications of current funding cuts on the program, and the main issues involved in decisions

about future courses of action.

The second workshop addressed issues in international collaboration in fusion research. Three

contractor reports, detailing the characteristics of

the major non-U.S. fusion programs and their

views of collaboration, were reviewed at the

workshop. The principal issues addressed were

the motivations and goals of foreign fusion programs, national security and competitiveness risks

of technology transfer through collaboration, and

other potential obstacles to collaboration,

The final workshop addressed fusion’s energy

context. Projections of electricity demand in the

21st century and their relevance to fusion were

presented by OTA consultants and reviewed. In

addition, the uncertainties inherent in forecasting supply and demand over times relevant to fusion were discussed. Alternative energy supply

technologies that might compete with fusion

were addressed, as were the implications of potential difficulties such as global climate change

and nuclear fission safety or environmental issues.

The material in this report is based on OTA staff

research, site visits, workshop discussions, advisory panel recommendations, and contractor and

consultant reports. The report is organized as

follows:

● Chapter 3 provides a brief history of the U.S.

fusion program, which, since its inception

in the 195os, has been almost entirely funded

by the U.S. Government.

●

●

●

●

●

Chapter 4 explains the technical underpinnings of fusion research and sets out the requirements for demonstrating fusion’s technological feasibility. Fusion research is one

of the Federal Government’s most futuristic

and technically complex undertakings. Physical theory and experimentation must advance the present state of the art if the goal

is to be reached; forefront technology must

be developed not only in the long-run, to

harness fusion, but in the short-run to construct each successive experiment.

Chapter 5 addresses the long-range energy

applications of fusion research. The anticipated characteristics of future fusion reactors

are discussed, including projected plant economic, safety, and environmental features.

Issues involved in commercializing the technology are also examined. In addition, factors that will be important in determining

whether and when fusion will penetrate

energy markets as a source of electricity are

discussed.

Chapter 6 discusses the character of current

fusion research and analyzes the value of the

fusion program in terms of its near-term,

non-energy benefits. Data on program participants, funding levels, and personnel levels

are summarized.

Chapter 7 examines the extremely important

role that international cooperation in fusion

research has had in the past and may have

in the future. Motivations for and obstacles

to future large-scale collaboration are assessed,

as well as possible models for such collaboration.

Finally, chapter 8 summarizes the critical issues facing the fusion program and presents

a series of policy paths for Congress to consider as it makes decisions on funding fusion

research. The implications of pursuing the

different paths are discussed.
Chapter 3

Fusion Research
CONTENTS

Page

Research Beginnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Nuclear Physics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Plasma Physics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Early Fusion Research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

The U.S. Fusion Program Through the Decades . . . . . . . . . . . . . . . . . . . . . . . . . . 40

The 1950s: Era of Optimism and Disillusionment. . . . . . . . . . . . . . . . . . . . . . . . 40

The 1960s:A Plateau . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

The 1970s: Rapid Growth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

The 1980s: Leveling Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Figures

Figure No. Page

3-1. Historical Magnetic Fusion R&D Funding, 1951-87 (in 1986 dollars) . . . . . . 41

3-2. Historical Magnetic Fusion R&D Funding, 1951-87 (in current dollars) .,.. 42
Chapter 3

History of Fusion Research

RESEARCH BEGINNINGS

Fusion research draws on two independent

branches of physics–nuclear physics and plasma

physics. Studying the fusion reaction itself is the

domain of nuclear physics. Studying the behavior

of matter u rider conditions necessary for fusion

reactions to take place is the focus of plasma

physics.

Nuclear Physics

Early in this century, the search for the causes

of radioactivity revealed that vast amounts of

energy were stored in an atom’s nucleus. As early

as 1920, this energy was hypothesized to be the

heat source that powered the sun and other stars.

With the discovery of the neutron in 1932 these

nuclear processes began to be understood, and

by the time efforts to control fusion reactions in

the laboratory began in the 195os, the nuclear

physics underlying laboratory fusion reactions

were well known. “Then, as now, ” noted a recent National Academy of Sciences panel reviewing physics research, “the obstacles to achieving controlled fusion lay not in our ignorance of

nuclear physics, but of plasma physics. ”2

I Most of the historical material in this chapter is based on Fusion: Science, Politics, and the Invention of a New Energy Source

(Cambridge, MA: MIT Press, 1982), a comprehensive and extensively documented history of the U.S. fusion program written by

Joan Lisa Bromberg under contract with the U.S. Department of

Energy. The book is restricted almost entirely to magnetic confinement fusion and covers a period ending in 1978. While Bromberg

was given access to unclassified and declassified DOE and national

laboratory records, the book does not represent the official position of DOE.

A more popularized history of the fusion program, covering inertial fusion as well as magnetic fusion and extending until 1983,

is found i n T.A. Heppenheimer, The Man-Made Sun: Hre Quest

for Fusion Power (Boston, MA: Little, Brown & Co., 1984),

2Natlonal Research Council, Panel on the Physics of Plasmas and

Fluids, Physics Survey Committee, Physics Through the 1990s:

P/asrnas and F/uids (Washington, DC: National Academy Press,

1986), p. 4,

Plasma Physics

Plasma physics, according to the same National

Academy review panel, is “the only major branch

of physics to come largely into being in the past

generation.”3 Its development drew upon a number of previously distinct and independent disciplines, pulling them together into a unified

methodology for the study of the plasma state.

Explaining plasmas could not begin until the

discovery of the electron in 1895 and the development of the atomic theory of matter. Between

1930 and 1950, the foundations of plasma physics

were laid, largely as a byproduct of investigations

on topics such as the earth’s outer atmosphere,

the sun, and various astrophysical phenomena.

The advent of space exploration and controlled

fusion research–the two major experimental

arenas for modern plasma physics—firmly established the field.

Early Fusion Research

The first probe into harnessing fusion power

took place during the Manhattan Project, the effort during World War II dedicated to developing an atomic bomb. Some physicists working on

the Manhattan Project in Los Alamos, New Mexico, began to consider whether the fusion process could be utilized in nuclear weapons. Such

investigations were not a high priority during the

war, however, because the national effort was

focused on developing weapons that utilized the

more immediately promising fission process.

In 1949, largely in response to the first Soviet

nuclear detonation, senior U.S. scientists and policymakers conducted an extensive, classified

(secret) debate about whether hydrogen bombs–

weapons that use the fusion process instead of

the fission process—could and should be developed. In 19s0, the debate ended when president

Truman approved a crash program to build such

jlbid., p, 6.

39

72-678 0 - 87 - 2
40 . Starpower: The U.S. and the International Quest for Fusion Energy

a weapon. The United States detonated its first

H-bomb in 1952.4

In the beginning, most research in thermonuclear fusion was weapons-related and classified. This research fell under the constraints of

the Atomic Energy Act of 1954, which mandated

that data concerning the “design, manufacture,

or utilization of atomic weapons, ” as well as “the

production of special nuclear material” and the

4Herbert York, “The Debate Over the Hydrogen Bomb, ” Scientific American, October 1975. There are many names for bombs

that use the fusion process: hydrogen bombs, H-bombs, and thermonuclear or hydrogen weapons. Such weapons can have many

times the explosive power of fission weapons.

“use of special nuclear material in the production of energy,” remain classified indefinitely unless specific action was taken to declassify its

Over the years, some of the emphasis in fusion

research shifted from weapons to reactors. Fusion reactors were sought not only to produce

“special nuclear materials’’—tritium and plutonium—needed for nuclear weapons, but also to

produce electricity. At the time, both energy production and materials production fell under the

restrictions of the Atomic Energy Act that mandated continued classification.

“’Special nuclear material,” as defined in the Atomic Energy Act

of 1954, is material capable of undergoing nuclear explosions.

THE U.S. FUSION PROGRAM THROUGH THE DECADES

The nature of the U.S. fusion research program

through each decade from its conception to the

present is summarized below. The funding profile for U.S. fusion research, both in constant and

current dollars, is shown in figures 3-1 and 3-2.

Data for these figures is provided in appendix C;

for more information on funding for magnetic fusion research, see chapter 6.

The U.S. Atomic Energy Commission (AEC) was

responsible for magnetic fusion research from

1951, when the program was formally undertaken, until 1974, when the AEC was disbanded

and replaced by the Energy Research and Development Administration (ERDA). In 1977, ERDA

in turn was disbanded and its responsibilities

transferred to the new Department of Energy

(DOE). Since 1977, DOE has managed the magnetic fusion research program.

The 1950s: Era of Optimism

and Disillusionment

Project Sherwood

From 1951 until 1958, fusion research was classified; during these years, the program was conducted under the code name “Project Sherwood.”

At the outset of Project Sherwood, both field scientists and program managers at the AEC believed

that fusion could yield an important technology

to supply future electricity needs. In pursuing fusion, scientists and AEC commissioners sought to

maintain U.S. scientific supremacy; there could

be significant political and economic advantage

should fusion lead to a commercially competitive new energy technology. Fusion research

would also support the U.S. weapons program.

The potential use of fusion reactors for generating weapons materials, as well as the possibility

of other military applications, was important to

the AEC; thus, during the early 1950s, fusion research grew along with military atomic research.

project Sherwood began optimistically in 1951.

At that time, it was estimated that spending about

$1 million over a period of 3 to 4 years would

be sufficient to learn whether a high-temperature

plasma could be confined by a magnetic field.

About that amount was budgeted for fusion research from 1951 to 1953. However, the problem proved harder than originally anticipated,

and in 1953 the fusion research program expanded. The personnel level increased from 8 in

1952 to 110 in 1955 and rose to over 200 people in 1956. Annual budgets increased from under

$1 million to $7 million over the same period.6

The United States established several fusion research centers. Federally funded efforts were con6Bromberg, Fusion, Op. Cit., P. 30.
Ch. 3.—History of Fusion Research ● 4 1

Figure 3-1 .—Historical Magnetic Fusion R&D Funding, 1951-87 (in 1988 dollars)

1955 1960 1965 1970

Year

ducted at Oak Ridge National Laboratory in Tennessee, Los Alamos Scientific Laboratory in New

Mexico, Lawrence Livermore Laboratory in California, and a number of universities, including

a major plasma physics laboratory at Princeton

University in New Jersey established primarily to

conduct fusion research. Private or corporatesponsored research began in 1956 at the General Electric Co. (GE) in New York and at the

newly created General Atomic Corp. in California. Several other companies dedicated a few staff

members to monitor the field.

Many different confinement schemes were explored during the early 1950s. Although proponents of the various schemes were careful to note

that practical applications lay at least 10 or 20

years in the future, the devices under study were

1975 1980

m

.

1985

.

SOURCE: U.S. Department of Energy, Office of Energy Research, letter to OTA project staff, Aug. 15, 1986.

thought to be capable of leading, in a straightforward process of extrapolation, to a commercial reactor. One report concluded in 1958:

With ingenuity, hard work, and a sprinkling of

good luck, it even seems reasonable to hope that

a full-scale power-producing thermonuclear device may be built within the next decade or two.7

In reality, very little was known about the behavior of matter under the conditions being studied, much less under reactor-like conditions. Experiments were trial-and-error operations, and

each one charted new ground. Results were often

7

Amasa S. Bishop, Project Sherwood.” The U.S. Program 

 (Reading, MA: Addison-Wesley Publishing Co., Inc.,

1958), p. 170. Bishop managed the AEC fusion program from 1953

to 1956 and again from 1965 to 1970.
42 . Starpower: The U.S. and the International Quest for Fusion Energy

Figure 3-2.—Historical Magnetic Fusion R&D Funding, 1951-87 (in currant dollars)

50

0L

1955 1980 1985 1970 1975 1980 1985

Year

SOURCE: U.S. Department of Energy, Office of Energy Research, letter to OTA project staff, Aug. 15, 1986.

ambiguous or misinterpreted, and the theoretical underpinnings of the research were not well

established. All devices investigated showed evidence of “instabilities,” or disturbances that grew

to the point where the plasma escaped confinement faster than expected. The devices studied

in the 1950s could not attain Lawson parameters

higher than about 1010 second-particles per cubic centimeter, a factor of about 10,000 less than

the minimum required to make net fusion power.8

‘The Lawson parameter is the product of density and confinement time (see 2, note 4). The units in which the Lawson parameter is expressed represent a density (particles per cubic centimeter) multiplied by a time (seconds), and have no immediate

physical significance. A product of 3 X second-particles per

cubic centimeter is considered the minimum for ignition in a D-T

reaction. (See discussion of “energy gain” in 4, pp. 67-68. )

Temperatures attained were about 100 electron

volts, in comparison to the minimum requirement

of 10,000 electron volts.9

Declassification

By the mid to late 1950s, the advantages of

declassifying Project Sherwood were recognized,

both within the AEC and among scientists in the

field. Some U.S. scientists had sought to delay

declassification of fusion research because they

were optimistic about harnessing controlled fusion reactions in the near future, and they rea9

An electron volt is a unit of energy. It is also used as a measure

of temperature, representing that temperature at which the average energy of plasma particles is roughly electron volt. (See 

2, note 3.)

44 ● Starpower: The U.S. and the International Quest for Fusion Energy

sense to classify fusion research, whose application in producing weapons material was still

hypothetical, after fission technology that was actually being used for that purpose was declassified.11

U.S. magnetic fusion research was declassified

in 1958 at the Second Geneva Conference on the

Peaceful Uses of Atomic Energy. Following declassification, it was apparent that the American, British, and Soviet programs were at more or less the

same level and were pursuing similar approaches

toward confining plasmas. Declassification opened

the door to widespread international cooperation

in fusion.

The 1960s: A Plateau

Fusion research in the United States proceeded

at a steady pace throughout the 1960s. The theoretical framework advanced, but discrepancies

between theoretical predictions and experimental

results were common. By the mid-1960s, Congress became impatient. In the late 1950s, members of Congress had believed that the Federal

program would beat the reactor prototype level

in 5 or 6 years. Since that time, fusion researchers realized that they had seriously underestimated the complexity of the problem. Therefore,

the researchers concentrated on studying plasma

behavior rather than on building reactor prototypes. Congress, however, worried that the researchers were building an array of different experiments that did not appear to be leading to

an attractive reactor.12 Thus, in 1963, the House

Appropriations Committee recommended a 16

percent cut in the program’s operating budget.

Much of the cut was restored, but the program

ended up with a budget of 7 percent less than

requested.

Enthusiasm for the fusion program cooled outside of Congress as well. While remaining supportive of fusion, AEC commissioners were more

interested in expanding the fission breeder reactor program .13 GE reviewed its corporate involvement in fusion in 1965 and concluded that

“the likelihood of an economically successful fu1 I Ibid., pp. 69, 72-73.

Izlbid., pp. 118-119.

IJlbid., p. 136.

sion electricity station being developed in the

foreseeable future is small.”14 GE proposed that

the AEC finance its research through a joint effort, but the AEC refused and GE phased out its

fusion program. While GE was reconsidering its

fusion program, the consortium of Texas utilities

that funded fusion research at General Atomic

in California withdrew its support.15 The AEC responded to this decision by funding much of

General Atomic’s fusion research itself in order

to preserve the expertise assembled there. In effect, this response created an additional national

laboratory.

In 1965, a prestigious outside review committee evaluated the fusion program. The committee found that the magnetic fusion program had

made significant progress, that the United States

needed to support research in order to develop

the technology, and that the program produced

“spin-off” technologies that could benefit the

economy. Moreover, the committee stated that

the United States would suffer a great loss of international stature if another country demonstrated the feasibility of fusion first. The committee recommended that the fusion budget increase

by 15 percent annually and that a new generation of experiments be funded to replace obsolete ones.16 After considerable deliberation within

the AEC and the Bureau of the Budget, an increase in funding was recommended, though not

of the magnitude suggested by the committee.

The Tokamak

By 1968, the highest temperatures that had

been achieved in a magnetic confinement fusion

device were only about 100 electron volts–not

appreciably higher than they were in the 1950s.

The quality of confinement, as measured by the

Lawson parameter, had increased by an order of

magnitude (factor of 10) to about 1011 secondparticles per cubic centimeter. In 1968, however,

Soviet scientists announced that they had exceeded the previous best values of each of these

parameters by an additional order of magnitude.

“1bid., p. 137.

I tThis consortium has continued to fund a modest level of fusion research at the University of Texas.

lbBromberg, Fusion, op. cit., pp. 138-139.
Ch. 3.—History of Fusion Research w 45

Photo credit: Princeton Plasma Physics Laboratory

Model C Stellarator at Princeton Plasma Physics Laboratory. Designed and built in the late 1950s, the Model C was

converted into the United States’ first tokamak in 1970.

Using a device named the “tokamak,” a Russian

acronym taken from the words for “toroidal

chamber with magnetic coil,” the Soviets claimed

to have generated ion temperatures of 500 electron volts, electron temperatures of twice that,

and a Lawson parameter of 1012 second-particles

per cubic centimeter.

The Soviet announcement both excited and

troubled the U.S. fusion community. U.S. program administrators worried that the Soviet

Union would beat the United States to demonstrating fusion’s feasibility. Some U.S. scientists

submitted proposals to build tokamaks in the

United States, while others argued that previous

plans to upgrade existing devices were more important. Many scientists were skeptical of Soviet

data, contending that it was ambiguous and not

sufficiently compelling to change the emphasis

of the U.S. program.

Early in 1969, the director of the Soviet fusion

effort invited a British team of scientists to bring

its own diagnostic equipment to Moscow to verify
—

46 . Starpower: The us. and the International Quest for Fusion Energy

Soviet research results. During the summer of

1969, the British team in Moscow announced its

preliminary findings: the Soviet results were genuine, and, in fact, the tokamak performed even

better than the Soviets had claimed. This announcement came shortly after the American scientific

community had decided to convert the premier

Princeton machine, the Model C stellarator, into

a tokamak. In addition, funds had been allocated

for the development of another tokamak at Oak

Ridge National Laboratory. After publication

the British findings, the U.S. program Iaunc

three more experimental tokamaks.

The 1970s: Rapid Growth

With the identification of the tokamak as

 of

ed

the

confinement concept most likely to reach reactorIevel conditions, the U.S. fusion program grew

rapidly. Between 1972 and 1979, the fusion program’s budget increased more than tenfold.

Three forces spurred this growth. First, uncertainty over long-range energy supply mobilized

public concern for finding new energy technologies. Second, fusion energy, with its potentially

inexhaustible fuel supply, looked especially attractive. Third, the growth of the environmental

movement and increasing opposition to nuclear

fission technology drew public attention to fusion

as an energy technology that might prove more

environmentally acceptable. The fusion program

capitalized on this public support; program leadership placed a very high priority on developing

a research plan that could lead to a demonstration reactor.

From Research to Development?

The emphasis on building a demonstration reactor dramatically changed the fusion program.

Previous fusion program plans had called for

“breakeven-equivalent” to be demonstrated in

a device containing only deuterium, to avoid the

complications introduced by use of tritium.17 The

new plans called for an experiment fueled with

deuterium and tritium (D-T), which would reach

breakeven by actually generating fusion power.

1 ~ritiu m is radioactive and difficu It to work with. More significantly, its use in fusion experiments generates neutrons that make

materials in the device radioactive.

During much of the 1970s, the director of the

fusion program was largely responsible for reorienting the program toward the use of tritium

in an experimental device. He sought to attain

breakeven with tritium for a number of reasons:18

●

●

●

●

Physics. The energy released in actual fusion

reactions involving tritium introduced a new

complication in device operation that could

significantly affect experimental behavior.

The director thought it was essential to study

the physical consequences of releasing fusion energy in a plasma.

Psychology. He also believed that too many

fusion scientists were interested in plasma

physics as a research enterprise, not as an

energy technology. Burning D-T, he thought,

wouId force them to come to grips with the

realities of fusion power instead of the abstractions of plasma physics.

Engineering. A D-T experiment would increase the amount of attention given to the

engineering aspects of a fusion reactor, departing from the near-total emphasis on

plasma physics in fusion research to date.

Politics. A D-T experiment would generate

actual fusion power for the first time. This

demonstration would dramatize to the public the capabilities of fusion in a more direct

way than simply achieving “breakeven-equivalent” conditions.19 Moreover, this demonstration had to take place soon enough so

that the fission breeder reactor would not become established as the long-run energy option of choice.

Many members of the fusion community opposed a D-T machine. They questioned whether

the scientific principles underlying tokamak operation were sufficiently known to take such a major step. Moreover, many felt that it was not necessary to construct an experiment at this point

in the research program that would involve radioactivity and thus more complications and more

expense.

18 Bromberg, Fusion, op. cit., PP. 204-205.

1

9

’’Breakeven-equivaIent” is the attainment of plasma conditions

in a deuterium-only plasma equivalent to those that, in a D-T

plasma, would produce breakeven. Breakeven-equivalent does not

require use of radioactive tritium and does not produce the neutron radiation generated in a breakeven D-T plasma.
Ch. 3.—History of Fusion Research ● 4 7

Photo credit: Princeton Plasma Physics Laboratory

The Tokamak Fusion Test Reactor at Princeton Plasma Physics Laboratory.

In mid-1 973, senior fusion researchers, fusion

program managers, and outside observers evaluated the plans to accelerate building a D-T machine. They concluded: 1 ) that scientific questions

should be answered in deuterium experiments,

which would be simpler and cheaper to build

than machines using tritium, but 2) that a 

burning experiment should be conducted on an

accelerated schedule.

During this period, congressional and public

concern about energy supply was increasing,

and, in June 1973, president Nixon announced

his intention to nearly double the budget proposed for energy research over the next 5 years.

By June 1974, the funding increases necessary to

pursue accelerated development of fusion were

appropriated. Planning began for a D-T burning

breakeven experiment, the Tokamak Fusion Test

Reactor (TFTR), to be constructed at the Princeton Plasma Physics Laboratory.

program organization also changed when Congress abolished the AEC in 1974 and transferred

its energy research programs to the Energy Research and Development Administration. ERDA

was a new agency with a broad mission in energy

research. It assumed management of AEC’s nuclear fission and fusion programs, as well as programs in solar and renewable technologies, fossil fuels, and conservation.

Concept Competition

The expansion of the tokamak program increased competition for funds among proponents
48 ● Starpower: The U.S. and the International Quest for Fusion Energy

of alternate confinement concepts. Most fusion

community leaders believed that the fusion program could not command the budget required

to construct more than one additional TFTR-class

experiment. Thus, there was some concern about

the role of the three remaining major fusion laboratories. Oak Ridge National Laboratory, which

had competed unsuccessfully with Princeton to

construct the tokamak breakeven experiment,

had tokamak experience that would be needed

to support the Princeton experiment. The future

was more uncertain for the non-tokamak research programs at Los Alamos and Lawrence

Livermore national laboratories.

Between the major concepts investigated at

these two labs, the “magnetic mirror” at Livermore was selected over the “theta pinch” at Los

Alamos to become the principal alternative to the

tokamak. Livermore had constructed a series of

mirror devices during the 1960s and 1970s, and,

in 1976, its proposal to build a greatly scaled-up

Mirror Fusion Test Facility (MFTF) was approved.

After design and construction of MFTF were

underway, researchers developed a design innovation that could improve the performance of the

mirror concept. This idea was tested by building

the Tandem Mirror Experiment (TMX) and found

to be valid. Even so, the improvement was too

small to justify changing the MFTF design, so construction proceeded as originally planned.

Livermore scientists then proposed another innovation that seemed to have the potential to

make a mirror reactor a viable competitor to a

tokamak reactor. This time, the gain appeared

to be sufficiently great to warrant modifying the

MFTF design, more than tripling its size. Moreover, Livermore scientists had so much confidence in the theory that they proposed to start

modifications to MFTF before testing the new

concept experimentally. In 1979, they proposed

to modify both TMX and MFTF in parallel, with

the smaller TMX-Upgrade (TMX-U) to be completed and operated to verify the new concept

at a time when substantial work still remained to

be done on the revised MFTF (now called MFTFB). In this way, any changes found to be necessary as a result of tests on TMX-U could be incorporated directly into MFTF-B during its construction. Construction of MFTF-B began in 1981.

Systems Studies

In addition to experiments on confinement

concepts, fusion program managers in the 1970s

began to consider design attributes of fusion reactors in a systematic way. Scientists and engineers began to address the engineering problems

that various confinement methods posed for reactor design, and “reactor relevance” soon became a driving force for additional research. Sustained and serious interest in these design studies,

also called systems studies, attracted the attention of people outside the fusion community.

Several individuals in electric utilities began to

follow fusion closely, and the utility research consortium, the Electric Power Research Institute

(EPRI), established a Fusion Advisory Committee.

World Effort

During the 1970s, the U.S. fusion program led

the world. It had the greatest breadth and depth

of confinement concepts under investigation, and

its attention to fusion systems and technology was

unmatched. However, programs in the Soviet

Union, Japan, and Western Europe grew during

the 1970s. Each program made plans to build a

TFTR-class tokamak to reach breakeven-equivaIent conditions: the Joint European Torus (JET) in

Europe, JT-60 in Japan, and the T-15 tokamak in

the Soviet Union. All of these machines except

the T-1 5 are now operational. The international

aspects of fusion research are discussed more

fully in chapter 7.

Program Reorientation

In 1977, president Carter incorporated the functions of ERDA, including the fusion program, into

a new agency, the Department of Energy. DOE

reemphasized support for nuclear fission, primarily due to concern over the proliferation aspects

of breeder reactors, and it increased support for

solar energy, conversion from oil and gas to coal,

and conservation .*0

The first director of the DOE Office of Energy

Research believed that the budget for the fusion

program was too large for fusion’s uncertain prospects. In his capacity as scientific advisor to the

2oBrom&rg, Fusion, op. cit., P. 235.
Ch. 3.—History of Fusion Research . 49

Photo credit: Lawrence Livermore National Laboratory

Installation of one of the end cell magnets for MFTF-B. Another view of this magnet is shown on p. 87.

Secretary of Energy, he commissioned a highIevel outside review of the program, a review that

he expected would recommend cutting the budget and relaxing the program’s emphasis on an

early demonstration reactor.21 On the contrary,

the review panel praised the management and

scientific achievements of the fusion program and

did not recommend budget cuts. Mostly as a reZ’ Ibid., p. 236.

suit of the panel’s findings, the Secretary of Energy

subsequently reaffirmed the near-term planning

of the fusion program. With few modifications,

DOE management supported maintaining current

budget levels, pushing towards early completion

and operation of TFTR, maintaining ongoing fusion system studies, and accelerating fusion technology development.

Although the short-term fusion program plans

continued much as before, the long-term strat-
50 . Starpower: The U.S. and the International Quest for Fusion Energy

egy under DOE in the late 1970s differed from

the ERDA strategy earlier in the decade. The review panel stated in its report that “the first objective of the program must be to determine the

highest potential of fusion as a practical source

of energy.” This meant not proceeding with construction of a tokamak device to succeed TFTR

until “a convincing case should be made that

Tokamaks can be engineered into attractive energy

producers.” 22 In effect, the committee recommended that the tokamak program be held up

at the TFTR stage until other devices, such as the

mirror, could be compared to it at relatively

equivalent stages of development.

Under DOE, the fusion program did not have

the sense of urgency that was so important earlier

in the decade. Fusion could not mitigate the

short-term oil and gas crisis facing the United

States. Furthermore, as a potentially inexhaustible long-range energy source (along with solar

energy and the fission breeder reactor), fusion

was not thought needed until well into the next

century. Therefore, there appeared to be no compelling reasons to develop a fusion demonstration plant rapidly .23

The 1980s: Leveling Off

The fusion program has continued to make

substantial technical progress during the 1980s.

Several world machines have the potential to

achieve breakeven, or breakeven-equivalent conditions, within the decade; in addition, significant

advances in plasma physics and fusion technology continue.24

ERAB Review of the Fusion Program,

1980

In 1980, the Energy Research Advisory Board

(ERAB), a standing committee that advises the

Secretary of Energy, established a committee to

review DOE’s fusion program. The committee’s

report evaluated technical progress in the fusion

zzFOster Committee, Final Report (DOE/ER-OO08, June 1978).

Quoted in T,A. Heppenheimer, The Man-Made Sun, op. cit., pp.

201-202.

zjBromberg, Fusion, op. cit., p. 247.

24ManY of the technica[ accomplishments in the fusion program

and the tasks still to be done are discussed in ch. 4 of this assessment.

program over the previous few years and found

many accomplishments that justified the panel’s

confidence that breakeven was near. The panel

concluded that:

. . . the United States is now ready to embark on

the next step toward the goal of achieving economic fusion power: Exploration of the engineering feasibility of fusion .25

The panel proposed that the program begin

planning a Fusion Engineering Device (FED),

which would provide a focus for development

of reactor-relevant technologies and components,

enable researchers to evaluate safety issues associated with fusion power, and facilitate investigation of additional plasma physics issues. This

device would be built and operated as part of a

broad program of engineering experimentation

and analysis to be conducted by a new fusion

engineering center. The ERAB panel recognized

that planning and constructing FED would require

a doubling of the fusion budget over the next 5

to 7 years, and it recommended this budget increase.

The Magnetic Fusion Energy

Engineering Act, 1980

Many of the recommendations of the ERAB

panel were incorporated into the Magnetic Fusion Energy Engineering Act (MFEE Act), passed

by Congress in September 1980.26 Passage of the

MFEE Act was largely a result of Representative

Mike McCormack’s (D-Washington) efforts. It

urged acceleration of the national effort in magnetic fusion research, development, and demonstration activities. Like the ERAB report, the act

recommended creation of a Magnetic Fusion

Engineering Center to coordinate major magnetic

fusion engineering devices.

The MFEE Act recommended that funding levels for magnetic fusion be doubled (in constant

dollars) within 7 years. However, it did not ap2t’’Report on the Department of Energy’s Magnetic Fusion Program,” prepared by the Fusion Review Panel of the Energy Research

Advisory Board, August 1980, as quoted in Fusion Energy: An Overview of the Magnetic Confinement Approach, /ts Objectives, and

Pace, a report prepared for the Subcommittee on Energy Research

and Production, House Committee on Science and Technology,

96th Cong., 2d sess., Serial GGG, December 1980, p. 133.

Zbpublic Law 96-386, signed into law on OCt. 7, 1980.
Ch. 3.—History of fusion Research ● 5 1

propriate these increases, and there was no follow-up. in effect, the act indicated that Congress

considered the fusion program worthwhile and

deserving of support but was unable or unwilling

to make a long-term commitment to substantially

increase expenditures. Actual appropriations in

the 1980s did not grow at the level specified in

the act and in fact continued the drop in constant dollar funding that began in 1977.

Reagan Administration Budgets

and Philosophy

Energy R&D budgets underwent radical cuts in

1981 at the beginning of the Reagan Administration. The Reagan Administration stated that development activity belonged in the private sector and that the government could encourage this

activity most effectively by staying out of it. Accordingly, DOE research budgets for solar energy,

fossil fuel technology, fission technology, and

energy conservation—those energy areas most

heavily weighted towards development or demonstration, as opposed to research—were substantially reduced. In contrast, the Reagan Administration continued to support government

funding for long-term, high-risk programs–e.g.,

fusion research–that would not attract private

investment. Therefore, although the fusion research budget has decreased in the 1980s, it has

not been cut as severely as some of DOE’s other

energy R&D programs.

With annual budget appropriations falling, the

ambitious plans of the 1970s, which culminated

in the MFEE Act of 1980, could not be implemented. Thus, the fusion program has had to

modify its program strategy; subsequent plans attempted to identify the most important aspects

of the fusion program to pursue.

The Comprehensive Program

Management Plan, 1983

The MFEE Act required that the Secretary of

Energy prepare a Comprehensive Program Management Plan (CPMP) outlining the fusion program’s strategy and schedule. This plan was completed by DOE and transmitted to Congress in

1983.27 The CPMP attempted to satisfy the emphases of the MFEE Act within the fiscal constraints imposed by the Reagan Administration.

The plan also sought to preserve the role of international leadership in fusion for the United

States.

The CPMP had a clear reactor emphasis, but

it was also consistent with Reagan Administration

philosophy towards development. The plan explicitly ruled out government construction of a

demonstration reactor, stating that:

The primary objectives of the [fusion] program

are designed to provide a technical basis for decisions by the private sector on whether to proceed with the commercial development of fusion

energy. Proceeding with a Federally funded demonstration plant is not part of this plan .28

The CPMP stated that within the next decade,

the fusion program would select a plasma confinement concept to undergo further development as a power reactor core. The plan defined

two stages that would permit a decision to be

made to build a demonstration reactor by the

year 2000.

ERAB Review of the Fusion Program,

1983

An additional provision of the MFEE Act established a technical panel on magnetic fusion as

an ERAB subcommittee. The subcommittee was

mandated to conduct a triennial review of the

fusion program, with the first such review to be

conducted in 1983.

The subcommittee’s report29 recognized that

budgetary constraints had made it impossible to

accomplish the goals of the MFEE Act on the timescale envisioned. The panel recommended that

DOE abandon the CPMP, stating that it would

force the program to make a choice between tanz7Compreben5;ve Program Management Plan (CPMP) for Magnetic Fusion Energy, June 1983. Submitted to the House Science

and Technology Committee by the Secretary of Energy pursuant

to the Magnetic Fusion Energy Engineering Act.

Zslbid., p. 2.

29 Energy Research Advisory Board, Magnetic Fusion Energy Research and ~eve/opment, Final Report prepared by the Technical

Panel on Magnetic Fusion of the Energy Research Advisory Board,

DOE/S-0026, January 1984.
52 ● Starpower: The U.S. and the International Quest for Fusion Energy

dem mirror and tokamak confinement concepts

before constructing another major device, a choice

that in turn would require delaying progress on

the tokamak. The paneI also noted that the CPMP’s

schedule called for construction of a next-generation engineering test reactor—a major facility

intended to explore engineering aspects of fusion

–before necessary technology development

could be completed.

As a revised program strategy, the ERAB panel

recommended that a tokamak follow-up device

to TFTR be built to study scientific issues. The

panel recommended that the reactor engineering efforts be postponed until additional resources

were available, and that a strong and innovative

base program be maintained in plasma physics,

technology development, and alternative confinement concepts.

The Magnetic Fusion Program Plan, 1985

DOE revised its program plan in response to

the criticisms of the ERAB subcommittee. In 1985,

DOE issued the Magnetic Fusion Program Plan

(MFPP), which stated that “the goal of the magnetic fusion program is to establish the scientific

and technological base required for fusion

energy. ”3° Unlike the CPMP, however, the MFPP

lessened the reactor emphasis, concentrated

more on the science and engineering requirements, and relaxed the schedule for fusion development:

The schedule for completing magnetic fusion

development is directly related to the technical,

economic, and political uncertainties associated

with energy supply, which are likely to exist for

several decades. The Magnetic Fusion Program

Plan is a strategy for solving fusion’s technical

problems within a time frame keyed to resolution

of other areas of energy development.31

Like the CPMP, the MFPP did not extend to

construction of a fusion demonstration reactor.

The plan laid out key technical issues that must

be resolved by the fusion program and set out

a goal of international collaboration, rather than

30U. S. Department of Energy, Office of Energy Research, A4agrretic Fusion Program Han, DOE/ER-0214, February 1985, Executive Summary.

311 bid .

international leadership, for the U.S. fusion

program.

ERAB Review of the Fusion Program,

1986

The second triennial review of the magnetic fusion program was completed by the ERAB subcommittee on magnetic fusion in November

1986. 32 The subcommittee endorsed the fusion

program’s direction, strategy, and plan and reaffirmed the need to investigate fusion energy as

“an attractive energy source of great potential for

the future.” The panel specifically considered two

issues of great importance to the future direction

of the program: 1 ) the construction of a Compact

Ignition Tokamak (CIT) as an experiment that

would extend scientific understanding beyond

that obtainable in TFTR; and 2) the role of international collaboration in an engineering test reactor project.

The Compact Ignition Tokamak.–Several

years of TFTR operation have shown continued

progress both in understanding and in achieving

confinement. TFTR has attained Lawson parameters above 1014 second-particles per cubic centimeter (a factor of 10,000 improvement over

1950’s results) and ion temperatures of 20,000

electron volts (a factor of 200 improvement). Attainment of actual breakeven when tritium is introduced seems highly probable, and the fusion

community has been actively exploring options

for a next step beyond TFTR. This has led to DOE

recommendations for CIT construction.

CIT will explore the physics associated with ignited plasmas. The ERAB subcommittee concluded

that CIT is “an essential and timely project,”33

both because it will address a fundamental physics

issue and because it will provide technical information and experience valuable to the engineering test reactor. ERAB recommended providing

an increment to the magnetic fusion program

budget to prevent funding for CIT from being

taken from other program areas. The construction cost of CIT, in 1986 dollars, has been esti32 Energy ResearchAdvisory Board, Repofl of the Technical pane/

on Magnetic Fusion of the Energy Research Advisory Board, prepared for the U.S. Department of Energy, November 1986.

JJlbid,, p. 1.
Ch. 3.—History of Fusion Research . 53

mated at $300 million for the facility, plus about

$60 million for diagnostic equipment and associated R&D. This estimate assumes that the facility will be located at Princeton Plasma Physics

Laboratory, where, according to DOE, site credits

will save about $200 million.34

The Role of International Collaboration.–The

subcommittee endorsed current DOE efforts in

international collaboration. In particular, the

panel supported the idea of constructing an international engineering test reactor. As envisioned,

this device—called the International Thermonuclear Experimental Reactor (lTER)—will be a large

ldlbid., p. 11, site credits refer to the savings that result from constructing the project at a location that already has some of the

needed equipment in place. By constructing CIT at Princeton, the

experiment will be able to take advantage of the existing T~R power

supplles and other equipment.

experimental facility designed to explore engineering and technological issues relevant to fusion reactors. The ERAB subcommittee stated that

“the United States should consider reaching out

to other nations to establish a multinational structure for fusion relationships. ”35 However, ERAB

also recognized the inherent complexity and uncertainty of major international collaborations,

pointing out that “some realistic consideration

must be given to the possibility that international

collaboration on a large scale may not come

about.” 36 At present, DOE is investigating the potential of undertaking a joint planning activity

with the other major fusion powers on a conceptual design for ITER, along with supporting R&D.

Jslbid., p. 14.

JGlbid,, p. 1 T. A detailed discussion of international collaboration on ITER and other projects can be found in ch. 7 of this

assessment.
Chapter 4

Fusion Science and Technology
Chapter 4

Fusion Science and Technology

Great progress has been made over the past

35 years of fusion research. Nevertheless, many

scientific and technological issues have yet to be

resolved before fusion reactors can be designed

and built. Fundamental questions in plasma science remain, especially involving the behavior

of plasmas that actually produce fusion power.

Other plasma science questions involve the behavior and operation of the various confinement

concepts that might be used to hold fusion

plasmas.

To date, engineering issues have not been studied as extensively as plasma science issues. For

many years, engineering studies were deferred

for lack of funds; science had a higher funding

priority. In addition, fusion technologies that require a source of fusion power to be tested and

developed have had to await a device that could

supply the power. Until recently, the fusion science database has not been sufficient to permit

such a device to be designed with confidence.

This chapter discusses the various confinement

concepts under study, the systems required in a

fusion reactor, and the issues that must be resolved before such systems can be built. It then

outlines the research plan required to resolve

these issues and estimates the amount of time and

money that such a research plan will take.

CONFINEMENT CONCEPTS’

Most of the fusion program’s research has focused on different magnetic confinement concepts that can be used to create, confine, and

understand the behavior of plasmas. In all of

these concepts, magnetic fields are used to confine the plasma; the concepts differ in the shape

of the fields and the manner in which they are

generated. These differences have implications

for the requirements, complexity, and cost of the

engineering systems that surround the plasma.

1 Th is chapter d Iscusses on Iy magnetic confinement approaches.

Other approaches to fusion are discussed In app. B. The concepts

mentioned In this section are described in greater detail in pp. 156-

204 ot’ Physics Through the 19905: P/asmas and F/uids, by the National Research Council (Wa~hington, DC: National Academy Press,

1 986).

Table 4-1 .—Classification of

Table 4-1 lists the principal confinement schemes

presently under investigation in the United States

and classifies them according to their level of development. The concepts are described in the following section.

At this stage of the research program, it is not

known which confinement concept can best

form the basis of a fusion reactor. The tokamak

is much more developed than the others, and

tokamaks are expected to demonstrate the basic

scientific requirements for fusion within a few

years. However, several alternate concepts are

under investigation in order to gain a better understanding of the confinement process and to

explore possibilities for improving reactor performance.

Confinement Concepts

Well-developed Moderately developed Developing

knowledge base knowledge base knowledge base

Conventional tokamak Advanced tokamak Spheromak

Tandem mirror Field-reversed configuration

Stellarator Dense Z-pinch

Reversed-field pinch

SOURCE Adapted from Argonne National Laboratory, Fusion Power Program, Technical Planning Activity Final Report,

commissioned by the U S Department of Energy, Off Ice of Fusion Energy, AN UFPP-87-1, January 1987, p 15

57
58 ● Starpower: The U.S. and the International Quest for Fusion Energy

The major scientific questions to be answered

for each confinement approach are whether and

with what confidence the conditions necessary

for a sustained, power-producing fusion reaction

can be simultaneously satisfied in a commercialscale reactor. Much of the experimental and

theoretical work in confinement studies involves

the identification and testing of scaling relationships that predict the performance of future devices from the results of previous experiments.

ideally, such scaling models should be derivable

from the basic laws of physics. However, the behavior of plasmas confined in magnetic fields is

so complicated that a general theory has not yet

been found. With some simplifying assumptions,

limited theoretical models have been developed,

but they are not broad enough to extrapolate the

behavior of a concept to an unexplored range.

Without a sound theoretical base, the risk of taking too large a step is great. A series of intermediate-scale experiments is needed to bridge the

gap between concept development and a fullscale reactor.

Even with the tokamak—the most studied confinement concept–scaling properties are not fully

understood. Although tokamaks have attained

by far the best experimental performance of any

confinement concept, no proven theoretical explanation of how that performance scales with

parameters such as size, magnetic field, and

plasma current has yet been derived. Without

a complete theoretical basis, “empirical” scaling

relationships deduced from past observations

must be used. Such empirical relationships may

well prove sufficient for designing a machine capable of forming reactor-scale plasmas before a

fundamental theoretical understanding of tokamak behavior is reached.

“Closed” Concepts

In “closed” magnetic confinement configurations, the plasma is contained by magnetic lines

of force that do not lead out of the device. Closed

configurations all have the basic shape of a doughnut or inner tube, which is called a “torus. ” A

magnetic field can encircle a torus in two different directions (figure 4-1 ). A field running the long

way around the torus, in the direction that the

tread runs around a tire, is called a “toroidal”

Figure 4-1 .—Tokamak Magnetic Fields

SOURCE: Princeton Plasma Physics Laboratory Information Bulletin NT-1: Fusion Power, 1984, p. 4.

field. This field is generally created by external

magnet coils, called toroidal field coils, through

which the plasma torus passes. A magnetic field

perpendicular to the toroidal field, encircling the

torus the short way, is called a “poloidal” field.

This field is generated by electrical currents induced to flow within the plasma itself. Together,

toroidal and poloidal magnetic fields form the total magnetic field that confines the plasma.
Ch. 4.—Fusion Science and Technology ● 5 9

Conventional Tokamak

In a tokamak, the principal confining magnetic

field is toroidal, and it is generated by large external magnets encircling the plasma. This field

alone, however, is not sufficient to confine the

plasma. A secondary poloidal field, generated by

plasma currents, is also required. The combination of poloidal and toroidal fields produces a total field that twists around the torus and is able

to confine the plasma (figure 4-1).

The tokamak concept was developed in the Soviet Union, and, since the Iate 1960s, it has been

the primary confinement concept in all four of

the world’s major fusion research programs. It

has also served as the principal workhorse for

developing plasma technology. The scientific

progress of the tokamak is far ahead of any other

concept. Major world tokamaks are listed in table 4-2.

Advanced Tokamak

Various features now under investigation may

substantially improve tokamak performance. Modifying the shape of the plasma cross-section can

increase the maximum plasma pressure that can

be confined with a given magnetic field. The

Doublet II I-D (D III-D) tokamak at GA Technologies and the Princeton Beta Experiment Modification (PBX-M) tokamak at Princeton Plasma

Physics Laboratory are being used to investigate

shaped plasmas according to this principle, Other

variants on tokamak design would permit more

compact fusion cores to be constructed, which

could lead to less expensive reactors; these improvements are under study.

Still other improvements would permit tokamaks to run continuously. The technique typically used today to drive the plasma current in

a tokamak can be run only in pulses. Technologies for driving continuous, or steady-state,

plasma currents are being investigated at a number of different experimental facilities.

Stellarator

The stellarator is a toroidal device in which

both the toroidal and poloidal confining fields are

generated by external magnets and do not depend on electric currents within the plasma. The

external magnets are consequently more complicated than those of a tokamak (figure 4-2).

However, the absence of plasma current in a stelIarator enables steady-state operation to be

achieved more directly without the need for current drive.

The stellarator concept was invented in the

United States. After the discovery of the tokamak

in the late 1960s, however, the United States converted its stellarators into tokamaks. The stellarator concept was kept alive primarily by research

Table 4-2.—Major World Tokamaksa

Device Location Status

JET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . European Community (United Kingdom) Operating

D III-D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United States (GA Technologies) Operating

Alcator C-Mod . . . . . . . . . i . . . . . . . . . . . . . . . . . . . . . . . United States (MIT) Under construction

T-14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . U.S.S.R. (Kurchatov) Under construction

TFTR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United States (PPPL) Operating

JT-60 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Japan (Naka-machi) Operating

T-15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . U.S.S.R. (Kurchatov) Under construction

ASDEX-Upgrade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Federal Republic of Germany (Garching) Under construction

Tore Supra. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . France (Cadarache) Under construction

Frascati Tokamak Upgrade . . . . . . . . . . . . . . . . . . . . . . Italy (Frascati) Under construction

PBX-M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United States (PPPL) Under construction

TEXTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Federal Republic of Germany (Julich) Operating

aListed in decreaing order of plasma current, one of the many parameters that determines tokamak capability. NO single factor by itself measures capability well; 

current is used here only to give a rough distinction between those devices at the top of the list and those at the bottom. Ranking by size, magnetic field, or other

parameter would rearrange the list somewhat.

NOTE: This table includes only the largest tokamaks. The World Survey of Activities in Corrtrolled Fusion Research, 1986 Edition (published in Nuclear Fusion, Special

Supplement 1966) lists a total of 77 existing and proposed tokamaks at 54 sites in 26 countries.

SOURCE Office of Technology Assessment, 1987
60 ● Starpower: The U.S. and the International Quest for Fusion Energy

Figure 4-2. —Magnet Coils for the Advanced Toroidal Facility, A Stellarator

SOURCE Oak Ridge National Laboratory

in the Soviet Union, Europe, and Japan, and, due

to good results, the United States has recently revived its stellarator effort. Stellarators today perform as well as comparably sized tokamaks.

Major world stellarator facilities that are operating or under construction are listed in table 4-3.

Not shown on the table is the Large Helical System proposed to be built in Japan at a cost several times that of the largest stellarator machine

now u

the new Japanese device would be the largest

operational non-tokamak fusion experiment,

Reversed-Field Pinch

In a reversed-field pinch, the toroidal magnetic

field is generated primarily by external magnets

and the poloidal field primarily by plasma currents. The toroidal and poloidal fields are comparable in strength, and the toroidal field reverses

nder construction; if built and operated, direction near the outside of the plasma, giving

Table 4-3.—Major World Stellaratorsa

Device Location Status

ATF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United States (ORNL) Under construction

Wendelstein VII-AS . . . . . . . . . . . . . . . . . . . . . . . . . . . . Federal Republic of Germany (Garching) Under construction

URAGAN-2M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . U.S.S.R. (Kharkov) Under construction

Heliotron-E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Japan (Kyoto University) Operating

URAGAN-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . U.S.S.R. (Kharkov) Operating

CHS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Japan (Nagoya University) Under construction

L-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . U.S.S.R. (Lebedev) Operating

H-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Australia (Canberra) Under construction

aListed in order of decreasing stored magnetic energy, a parameter which in turn depends both on magnetic field strength and plasma 

SOURCE Office of Technology Assessment, 1987; from data provided by Oak Ridge National Laboratory,
Ch. 4.—Fusion Science and Technology “ 61

Figure 4-3.— Reversed. Field Pinch

Toroidal field

windings

SOURCE: Adapted from National Research Council, Physics Through the 1990s:

Plasmas and FluIds (Washington, DC: National Academy Press, 1988).

the concept its name (see figure 4-3). In a tokamak, the toroidal field dominates and points in

the same direction throughout the plasma.

The reversed-field pinch generates more of its

magnetic field from plasma currents and less from

external magnets, permitting its external magnets

to be smaller than those of a comparably performing tokamak. The nature of the magnetic

fields in a reversed-field pinch may also permit

steady-state plasma currents to be driven in a

much simpler manner than is applicable in a tokamak. Moreover, a reversed-field pinch plasma

may be able to heat itself to reactor temperatures

without the complex and costly external heating

systems required by tokamaks.

Los AIamos National Laboratory in New Mexico is the center of U.S. reversed-field pinch research. The Confinement Physics Research Facility (CPRF) to be built there will hold the largest

reversed-field pinch device in the United States.

A variant of the reversed-field pinch, the Ohmically Heated Toroidal Experiment, or OHTE, was

built at GA Technologies in San Diego, California. Reversed-field pinch research is also conducted in both Europe and Japan. Table 4-4 lists

the major world reversed-field pinches.

Spheromak

The spheromak is one of a class of less developed confinement concepts called “compact

toroids,” which do not have toroidal field coils

linking the plasma loop and therefore avoid the

engineering problem of constructing rings locked

within rings. Conceptually, if the torodial field

coils and inner walls of a reversed-field pinch

were removed and the central hole were shrunk

to nothing, the resultant plasma would be that

of the spheromak. Its overall shape is spherical;

although the internal magnetic field has both

toroidal and poloidal components, the device has

no central hole or external field coil linking the

plasma (figure 4-4). The plasma chamber lies entirely within the external magnets. If the spheromak can progress to reactor scale, its small size

and simplicity may lead to considerable engineering advantages. However, the present state of

knowledge of spheromak physics is rudimentary.

Table 4.4.—Major World Reversed-Field Pinchesa

Device Location Status

CPRF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United States (LANL) Under construction

RFX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Italy (Padua) Under construction

OHTE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United States (GA Technologies) Operating

HBTX 1-B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United Kingdom (Culham) Operating

ZT-40M . . . ! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United States (LANL) Operating

MST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United States (University of Wisconsin) Under construction

ETA BETA 11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ., Italy (Padua) Operating

Repute I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Japan (Tokyo University) Operating

TPE-1RM(15) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Japan (Tsukuba University) Operating

STP-3M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Japan (Nagoya University) Operating

aListed in order of decreasing plasma current, a rough measure of reversed-field pinch performance.

SOURCE: Office of Technology Assessment, 1987; from data supplied by the Los Alamos National Laboratory.
62 “ Starpower: The U.S. and the International Quest for Fusion Energy

Figure 4-4.—Spheromak

Spheromak research at Los Alamos National

Laboratory was terminated in 1987 due to fiscal

constraints, and another major U.S. device at

Princeton Plasma Physics Laboratory is to be terminated in fiscal year 1988. The remaining U.S.

spheromak research effort takes place at the University of Maryland. Spheromaks also are being

studied in Japan and the United Kingdom. Major world spheromak devices are listed in table

4-5.

Field= Reversed Configuration

The field-reversed configuration (FRC) is another

form of compact toroid. Despite the similar name,

it does not resemble the reversed-field pinch. It

is unusual among closed magnetic confinement

concepts in providing confinement with only

poloidal fields; the FRC has no toroidal field. The

plasma is greatly elongated in the poloidal direction and from the outside has a cylindrical shape

(figure 4-5).

Like the spheromak, the FRC does not have external magnets penetrating a hole in its center;

all the magnets are located outside the cylindrical plasma. The FRC also has the particular virtue of providing extremely high plasma pressure

for a given amount of magnetic field strength. if

its confining field is increased in strength, the FRC

plasma will be compressed and heated. Such

heating may be sufficient to reach reactor conditions, eliminating the need for external heating. Existing FRC plasmas are stable, but whether

stability can be achieved in reactor-sized FRC

plasmas is uncertain. A new facility, LSX, is under

construction at Spectra Technologies in Bellevue,

Washington, to investigate the stability of larger

plasmas.

U.S. FRC research started at the Naval Research

Laboratory in Washington, D. C., in the late 1960s.

Increased effort in the United States in the late

1970s, centered at Los Alamos, was undertaken

largely in response to experimental results obtained earlier in the decade from the Soviet Union

Table 4-5.—Major World Spheromaksa

Device Location Status
Ch. 4.—Fusion Science and Technology “ 63

Figure 4-5.— Field-Reversed Configuration

SOURCE: National Research Council, Physics Through the 1990s: Plasmas and

Fluids (Washington, DC National Academy Press, 1988),

and the Federal Republic of Germany. Soviet research has continued, but German and British research programs have stopped. Meanwhile, a

program in Japan has begun. Major field-reversed

configuration experiments around the world are

listed in table 4-6.

"Open” Concepts

plasmas in open magnetic confinement devices

are confined by magnetic fields that do not close

back on themselves within the device but rather

extend well outside the device. Since plasma particles can easily travel along magnetic field lines,

some additional mechanism is required to reduce

the rate at which plasma escapes out the ends

of an open confinement device.

Magnetic Mirrors

Fusion plasmas can be confined in an openended tube by strengthening, and thereby compressing, the magnetic fields near the ends.

Strengthening the magnetic field near the ends

“reflects” plasma particles back into the center

much as narrowing the ends of a sausage helps

keep in the meat. However, the ends of a simp/e magnetic mirror (figure 4-6a) are not otherwise sealed. Just as the meat eventually forces its

way out of an unsealed sausage when squeezed,

a simple magnetic mirror cannot confine a plasma

well enough to generate fusion power. In addition, simple mirrors are usually unstable, with the

plasma as a whole tending to slip out sideways.

A variation of the simple mirror is the minimum-B mirror (figure 4-6 b), one version of which

uses a coil shaped like the seam on a baseball

to create a magnetic field that is lowest in strength

at the center and increases in strength towards

the outside. Particles leaving the center tend to

be reflected back by the increasing magnetic field

at the outside, just as particles leaving the simple mirror tend to be reflected back at the ends.

This configuration is stable, and there is no tendency for the plasma as a whole to escape. However, despite these improvements, the minimumB mirror cannot confine a plasma well enough

to generate net fusion power.

The tandem mirror (figure 4-6c) improves the

simple magnetic mirror by utilizing additional

mirrors to improve the plugging at each end.

These plugs, called end cells, are themselves magnetic mirrors. Rather than trapping the main

plasma, the end cells hold particles that generate an electric field. This electric field, in turn,

keeps the plasma in the central cell from escapable 4.6.—Major World Field-Reversed Configurationse

Device Location Status

LSX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United States (Spectra Technologies) Under construction

FRX-C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United States (LANL) Operating

BN, TOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . U.S.S.R. (Kurchatov) Operating

TRX-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . United States (Spectra Technologies) Operating

OCT, PIACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Japan (Osaka University) Operating

NUCTE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Japan (Nihon University) Operating

aListed approximately by decreasing order of size; similarly sized devices at the same institution are listed together.

SOURCE Office of Technology Assessment, 1987; from information supplied by the Los Alamos National Laboratory.
64 ● Starpower: The U.S. and the International Quest for Fusion Energy

Figure 4-6.—Magnetic Mirrors

(a) Simple mirror (b) Minimum-B mirror

Plasma

/

SOURCE: Lawrence Livermore National Laboratory, “Evolution of the Tandem Mirror,” Energy and Technology Review, November

1986

ing. While particle losses from the end cells are

high, these losses can be compensated by injecting new particles.

The tandem mirror concept was developed

simultaneously in the United States and the Soviet Union in the late 1970s. The Mirror Fusion

Test Facility B (MFTF-B), located at Lawrence

Livermore National Laboratory in California, is

the largest mirror device in the world and the

largest non-tokamak magnetic confinement fusion experiment. Budget cuts, however, forced

MFTF-B to be moth balled before it could be used

experimentally. The Tandem Mirror Experiment

Upgrade (TMX-U) at Livermore, a smaller version

of MFTF-B, was terminated as well, and the TARA

device at the Massachusetts Institute of Technology will be shut down in 1988. At that point,

Phaedrus at the University of Wisconsin will be

the only operational U.S. mirror machine. Mirror research is still conducted in the Soviet Union

and Japan. Table 4-7 presents a list of major world

tandem mirror facilities.

Dense Z= Pinch

In this concept, a fiber of frozen deuteriumtritium fuel is suddenly vaporized and turned into

plasma by passing a strong electric current through

it. This current heats the plasma while simultaneously generating a strong magnetic field encircling

the plasma column (figure 4-7), “pinching” it long

enough for fusion reactions to occur. Many devices investigated in the earliest days of fusion

research in the 1950s operated in a similar manner, but they were abandoned because their

plasmas had severe instabilities and were unable to approach the confinement times needed

to generate fusion power.

The dense z-pinch differs from the 1950s pinches

in several important aspects that, as calcuIations

and experiments have shown, improve stability.

Crucial to the modern experiments are precisely

controlled, highly capable power supplies that

would have been impossible to build with 195os

technology, and the use of solid, rather than gase-
—

Ch. 4.—Fusion Science and Technology ● 6 5

Table 4-7.—Major World Tandem Mirrorsa

Device Location Status

MFTF-B . . . . . . United States (LLNL) Moth balled

TMX-U . . . . . . . United States (LLNL) Mothballed

Gamma-10 . . . .Japan (Tsukuba University) Operating

TARA . . . . . . . . United States (MIT) To be terminated, fiscal year 1988

Phaedrus . . . . . United States (University of Wisconsin) Operating

Ambal M . . . . . USSR (Novosibirsk) Under construction

aListed in decreasing order of size.

SOURCE: Office of Technology Assessment, 1987; from data supplied by the Lawrence Livermore National Laboratory.

Figure 4-7. —Dense Z-Pinch

SOURCE: Office of Technology Assessment, 1987

OUS, fuel to initiate the discharge. However, it is

much too early to tell whether this concept can

be developed successfully. If the concept can be

developed, the device has the potential to be far

smaller and far less expensive than devices based

on other concepts. External magnets are not

needed since the plasma current supplies the entire confining field. Dense z-pinch research is taking place in the United States at two facilities: the

Naval Research Laboratory and Los Alamos National Laboratory.

Conclusions Concerning

Confinement Approaches

A number of general conclusions can be drawn

from studies of the confinement concepts that

have evolved over the past 10 to 15 years:

●

●

●

Many fusion concepts are under study because the frontrunner tokamak, while likely

to be scientifically feasible, may yet be found

weak in some critical area or less economically attractive than alternatives. Features

being studied in alternate concepts include

eased conditions for steady-state operation,

reduced external magnet complexity and

cost, and improved use of the magnetic field.

Searching for optimum reactor configurations and developing further understanding

of the fusion process mandate that the range

of concepts under investigation not be

prematurely narrowed.

The tokamak concept is by far the most

developed, and it has attained plasma conditions closest to those needed in a fusion

reactor. At present and for the next several

years, studies of reactor-like plasmas will be

done with tokamaks because no other concept has yet proven that it can reach reactor

conditions. A number of other confinement

concepts have features that might make

them preferable to the tokamak if they are

capable of progressing to an equivalent stage

of performance. It remains to be seen which

of these concepts will attain that performance level, what their development will cost,

and to what degree the tokamak concept itself will further improve.

Different confinement studies complement

each other. Knowledge obtained through research on a specific concept often can be

generalized. Throughout the history of fusion

research, plasma science issues originally investigated because of their relevance to a

particular concept have become important

to studies of other concepts as well.

A great deal of progress in understanding

fusion plasmas and confinement concepts

has been made to date. Many concepts
66 ● Starpower: The U.S. and the International Quest for Fusion Energ y

●

●

studied earlier, such as the simple magnetic

mirror, are no longer studied today because

they cannot compare attractively to improved

or alternate concepts. At the same time, as

in the case of the dense z-pinch, problems

once considered intractable may be solved

with additional scientific understanding and

more advanced technology.

Research on all confinement concepts has

benefited from international cooperation.

Studies undertaken by different groups in

different countries enhance each other significantly. Furthermore, advances by one

program have frequently stimulated addi- ●

tional progress in other programs. international cooperation in fusion research is discussed further in chapter 7.

Not all confinement concepts can be develrequire study at greater levels of capability

before their potential as reactor candidates

can be assessed. Moreover, since this has

largely been an empirical program, advanced

studies will require larger and increasingly

more expensive facilities. Fiscal constraints

will almost certainly require that not all of

the concepts be “promoted” to subsequent

stages of development. Criteria such as development cost, characteristics of the end

product, and likelihood of success must be

developed for selecting which concepts are

to be pursued further.

progress in fusion science depends on progress in fusion technology. Time after time,

the exploration of new ranges of plasma behavior has been made possible by the development of new heating, fueling, and plasma

oped to reactor scale. Promising concepts shaping technologies.

SCIENTIFIC PROGRESS AND REACTOR DESIGN

Different Dimensions of Progress

To form the basis of a viable fusion reactor, a

confinement concept must meet two objectives.

First, it must satisfy scientific performance requirements—temperature, density, and confinement

time—necessary for a plasma to produce fusion

power. progress towards those requirements is

easy to measure.

Second, a confinement concept must demonstrate “reactor potential. ” Unlike scientific performance, reactor potential is difficult to measure. A viable reactor must be built, operated, and

maintained reliably, and it must be economically,

environmentally, and socially acceptable. While

fusion’s acceptability in these respects depends

on factors external to fusion technology, it also

depends on the choice of confinement concept.

Each concept may have different advantages,

and, in the absence of quantitative measures, the

process of i dentifying the concepts t hat offer t he

most attractive reactors depends in large part on

the innovation and technological optimism of the

reactor designer. Also, attributes of an attractive

reactor can be identified today, but the relative

importance of these attributes may change as our

understanding of fusion technology and future

societal needs improves.

No matter how it is evaluated, reactor potential is a requirement that, along with scientific performance, must be satisfied by at least one confinement concept before fusion power can be

realized. Figure 4-8 shows two different paths by

which a concept can develop toward commercial use. Along the “performance-driven” path,

a concept first demonstrates the ability to attain

plasma parameters near those required to produce fusion power; subsequently, innovations or

successive refinements show that the concept’s

scientific capabilities can be used in a viable reactor design. Alternatively, along the “conceptimprovement-driven” path, features that are attractive in a fusion reactor—e.g., compact size,

ease of maintenance, simple construction, and

reliable operation—are apparent before the scientific performance necessary to produce fusion

power is demonstrated.

The actual development of any given confinement concept will fall somewhere between these

extremes. Development of the tokamak appears

to be closer to the performance-driven curve. Its

scientific performance, along with its use in de-
Ch. 4.—Fusion Science and Technology ● 6 7

Figure 4-8.—Alternate Paths for Concept Development

SOURCE Adapted from Argonne National Laboratory, Technical Planning Activity: Final Report, commissioned by the U.S. Department of Energy, Office of Energy

Research, AN L/FPP-87-1, January 1987, figure 1.5, p. 56.

veloping plasma technology and diagnostics, has

been the primary motivation for study to date;

improvements to the basic tokamak concept are

currently focused on improving reactor potential. Other concepts are more concept-improvement-driven in that their features might make

them preferable to the tokamak if they can reach

reactor scale. However, the ability of other concepts to attain the necessary plasma conditions

is much less certain because their experimental

databases are less developed.

Scientific Progress

Energy Gain

An important measure of scientific progress

towards attaining reactor-relevant conditions is

energy gain, denoted as “Q. ” Energy gain is the

ratio of the fusion power output that a device generates to the input power injected into the plasma.

Input and output power are measured at some

instant after the plasma has reached its operating density and temperature. In experimental

plasmas that do not contain tritium and therefore

do not produce significant amounts of fusion

power, an “equivalent Q“ is measured. It is defined as the Q that would be produced by the

plasma if it were fueled equally by both deuterium and tritium (D-T) and if it had attained the

same plasma parameters. z

The numerator of the Q ratio includes all the

fusion power produced by the plasma, even

though most of the output power (80 percent)

“’Equivalent Q“ is either calculated from the measured plasma

density and temperature or derived from actual measurements of

deuterium-deuterium (D-D) fusion reactions. Since the ratio between the D-T reaction rate and the D-D reaction rate under the

same conditions IS believed known, a measurement of D-D reactions can be used to infer what the D-T fusion yield would be

under the same conditions.
68 “ Starpower: The U.S. and the International Quest for Fusion Energy

immediately escapes from the plasma via energetic neutrons. The denominator of the ratio–

the power used to heat the plasma—greatly underestimates the amount of power actually consumed. Losses incurred in generating heating

power and delivering it to the plasma are not included, nor is the power needed for the confining magnets, vacuum system, and other support

systems. In present-generation experiments, the

power excluded from the definition of Q is as

much as 35 times greater than the power accounted for in this ratio.3

Q excludes most of the power drawn by a fusion experiment because it is a scientific measure that is not intended to gauge engineering

progress. Present experiments, needing only to

operate for short pulses, have not been designed

to minimize consumed power; to lessen construction cost, they use magnets that are far less efficient than those likely to be used in future reactors. Similarly, the inefficiencies in generating

the externally applied plasma heating power are

not included because auxiliary heat is not required once a plasma generates enough fusion

power to become self-sustaining. Even so, some

external power will be required in any steadystate plasma device except the stellarator to maintain electrical currents within the plasma.

Figure 4-9 shows the plasma temperatures and

confinement parameters needed to obtain Qs of

at least 1, a condition known as “breakeven. ”

The plasma temperatures and confinement parameters that have been attained experimentally

by various confinement configurations are also

shown. No device has yet reached breakeven,

although tokamak experiments have clearly come

the closest.

Ignition

The most significant region in figure 4-9 is ignition in the top right corner. An ignited D-T

plasma not only generates net fusion power but

also retains enough heat to continue producing

fusion reactions without external heat. The Q of

an ignited plasma is infinite, since the plasma genJsee specifications for the Tokamak Fusion Test Reactor at the

Princeton Plasma Physics Laboratory, footnote 4 below.

crates output power without auxiliary input power

from external sources. (Power to drive currents

in the plasma and to cool the magnets to their

operating temperature will be required even for

ignited plasmas, but, as stated above, this power

is not included in Q.)

Successfully reaching ignition—or at least successfully generating a plasma that produces many

times more power than is input into it—will be

a major milestone in determining fusion’s technological feasibility. The energy and the reaction

products generated in a plasma producing appreciable amounts of fusion power will significantly

affect the plasma’s behavior. Understanding these

effects may be crucial to utilizing self-sustaining

fusion reactions in reactors, and these effects cannot be studied under breakeven conditions alone.

Breakeven

The breakeven curve in figure 4-9 shows the

conditions under which a plasma generates as

much power through fusion reactions as is injected into it to maintain the reactions. Although

reaching breakeven will be a major accomplishment, it will not have the technical significance

of reaching ignition. Due to the way that energy

gain is defined, the breakeven threshold in some

respects is arbitrary, and it depends significantly

on the manner in which the plasma is heated.

Crossing the threshold does not cause a significant change in plasma behavior and in no way

indicates that the experiment is able to power itself. Problems that are not fully evident under

breakeven conditions may yet be encountered

on the way to ignition.

The breakeven curve in figure 4-9 is calculated

for plasmas that are uniformly heated. If the

plasma is heated in such a way that a small fraction of the plasma particles become much hotter than the rest, this fraction will produce a disproportionate amount of fusion power and the

breakeven requirements can be substantially lowered. For this reason, plasmas heated with neutral beams can reach breakeven under conditions

that would not be sufficient without the use of

neutral beams.

Neutral beams are extremely hot jets of neutral atoms that can penetrate the confining mag-
Ch. 4.—Fusion Science and Technology ● 6 9

10

1

0.1

Figure 4-9.— Plasma Parameters Achieved by Various Confinement Concepts

Confinement parameter (particle –see cm-3)

KEY: S-1: Spheromak-1; Princeton Plasma Physics Laboratory, Princeton, NJ.

TMX-U: Tandem Mirror Experiment Upgrade; Lawrence Livermore National Laboratory, Livermore, CA.

ZT-40M: Toroidal Z-pinch, -40, Modified; Los Alamos National Laboratory, Los Alamos, NM.

FRX-C: Field-Reversed Experiment C; Los Alamos National Laboratory, Los Alamos, NM.

OHTE: Ohmically Heated Toroidal Experiment; GA Technologies, Inc., San Diego, CA.

Gamma-IO: University of Tsukuba, Ibaraki, Japan.

WVII-A: Wendelstein VII-A; Institute for Plasma Physics, Garching, Federal Republic of Germany.

HEL-E: Heliotron-E; Kyoto University, Kyoto, Japan.

D Ill: Doublet Ill; GA Technologies, Inc., San Diego, CA.

JET: Joint European Torus; JET Joint Undertaking, Abingdon, United Kingdom.

TFTR: Tokamak Fusion Test Reactor; Princeton Plasma Physics Laboratory, Princeton, NJ.

ALC-C: Alcator C; Massachusetts Institute of Technology, Cambridge, MA.

SOURCE Office of Technology Assessment, 1987.

netic fields to enter the plasma. Beam atoms collide with particles inside the plasma and become

electrically charged, thereby becoming trapped

by the magnetic field. Through collisions, much

of the energy carried by the beams is transferred

to the “target” plasma, heating it up. In the process, the beam particles themselves cool down.

However, it will take many collisions for the

beam particles to cool down to the temperature

of the target plasma. As long as the beams are

on, the most recently injected beam particles are

significantly hotter than the original plasma particles. (Once the beams are turned off, the injected particles cool down to the temperature of

the remaining plasma.) Since the fusion reaction

rate increases very rapidly with temperature, the

hotter particles from the neutral beam have a

much higher probability of generating fusion reactions than other particles in the plasma. in this

manner, a beam-heated plasma can achieve

breakeven with plasma parameters up to a factor of 10 lower than those needed for plasmas

heated by other mechanisms. However, since the
70 ● Starpower: The U.S. and the International Quest for Fusion Energy

beams themselves require so much power to

operate, it is not expected that beam-heated

plasmas will be used in reactors. Therefore, the

lower breakeven threshold for beam-heated

plasmas may not translate into lower requirements for a practical reactor.

The Tokamak Fusion Test Reactor (TFTR) at

Princeton Plasma Physics Laboratory was designed to take advantage of beam heating. It is

expected that breakeven-equivalent (breakeven

conditions in a plasma not containing tritium) will

be obtained sometime between fall 1987 and

spring 1988. Experiments to realize true breakeven using tritium are scheduled for the end of

1990. These achievements will be important because, for the first time, a significant amount of

heat from fusion power will be produced in a

magnetic fusion device. Moreover, successful D-T

operation of TFTR will provide important tritiumhandling experience necessary for future reactor

operation.

Nevertheless, TFTR–not being an engineering

facility–does not address most of the technological issues that must be resolved before a fusion

reactor can be built. Moreover, it will not reach

ignition, and the advantage it derives from using

neutral beams will probably not translate into a

workable reactor. It does not incorporate advanced physics aspects that have been identified

since its design in the 1970s. TFTR will not—and

never was intended to—have the capability to

generate electricity from the fusion power it will

produce. Even on attaining breakeven, the TFTR

experiment as a whole—as opposed to the TFTR

plasma alone—will produce less than 3 percent

of the power it will consume.4

State of the Art

Temperature and Confinement.–Figure 4-9

shows results that have been attained by each

4

TFTR is being upgraded to deliver up to 27 megawatts of neutral beam power to the plasma. To reach breakeven, where the

fusion power generated equals the external power injected into

the plasma, 27 megawatts of fusion power would have to be generated in the plasma. If reaching breakeven were to require TFTR

to draw near the maximum amount of power available from its electrical supply, it could consume close to 1,000 megawatts of electricity. This amount IS 37 times greater than the fusion power to

be produced at breakeven.

of the confinement concepts to date. Tokamak

experiments have clearly made the most progress

in terms of coming the closest to the ignition

region.

TFTR, in particular, has reached the highest

temperature and confinement parameters of any

magnetic fusion experiment. In 1986, TFTR attained ion temperatures of 20 kiloelectron volts

(kev) or more than 200 million degrees C, well

over the temperature needed for breakeven or

ignition. However, these high-temperature results

were obtained in a relatively low-density plasma

having a confinement parameter of 1013 secondparticles per cubic centimeter, which is about half

of the confinement parameter needed to reach

breakeven at that temperature. The equivalent

Q actually attained by the plasma was 0.23. Use

of neutral beam heating under these conditions

reduces the breakeven threshold by almost a factor of four; a plasma heated to 20 keV without

the use of neutral beams would need a confinement parameter 7.5 times higher than was attained to reach equivalent breakeven.

In a separate experiment at a lower temperature of 1.5 keV, TFTR reached a confinement parameter of 1.5 X 1014 second-particles per cubic

centimeter. Had this confinement been attained

at a temperature of 20 keV, TFTR would have

been well above equivalent breakeven, coming

close to meeting the equivalent ignition condition. However, in practice, TFTR will not be able

to attain temperature and confinement values this

high simultaneously. Temperature can be raised

at the expense of confinement, and vice versa,

but the product of the two–which determines

equivalent Q—is difficult to increase. With additional neutral beam power and other improvements, TFTR may well be able to raise its equivalent Q from 0.23 to 1 and reach equivalent

breakeven. However, it is extremely unlikely that

equivalent Qs much greater than 1 are attainable in TFTR.

Beta.–The beta parameter, also called the

“magnetic field utilization factor, ” measures the

efficiency with which the energy of the magnetic

field is used to confine the energy of the plasma.

Beta is defined as the ratio of the plasma pres-
Ch. 4.—Fusion Science and Technology c 71

Photo credit: Princeton Plasma Physics Laboratory

The PBX tokamak at Princeton Plasma Physics

Laboratory.

sure to the magnetic field pressures Record tokamak values for beta of 5 percent, in the PBX experiment at Princeton Plasma Physics Laboratory,

and 6 percent, in the D II I-D experiment at GA

Technologies, have been attained. These results

are especially important in that they generally

validate theoretical models that predict how further improvements in beta can be obtained.

In a fusion reactor, the fusion power output per

unit volume of the plasma would be proportional

to beta squared times the magnetic field strength

to the fourth power. Since tokamaks have relatively low betas compared to many of the other

confinement concepts currently studied, improving the beta of tokamaks can be useful. Betas

greater than 8 percent are indicated in some system studies as being necessary for economical

performance,6 and values considerably exceed-

~plasma pressure IS equal to plasma temperature times density

and is proportional to the plasma energy per unit volume; magnetic field pressure, which is proportional to the square of the magnetic field strength, is a measure of the energy stored in the magnetic field per unit volume.

Typical reactor studies indicate that the plasma in an operating

fusion reactor WIII have a pressure several times that of the earth’s

atmosphere at sea level, The plasma density, however, will only

be about 1/1 00,000 the density of’ the atmosphere at sea level That

so tew par-t lcles can exert such a h lgh pressure IS a measure ot thel r

extreme tern peratu re about 10,000 electron volts, or more than

100 million degrees C.

6For ~xam Pie, J, Sheffield, et a[., Cost Assewnent of.? ~eflerlc

Magnet/c Fus/orr Rex-tor, oak Rlcige National Laboratory ,

(3RNLKM-931 1, March 1986, p. 5.

ing that have been obtained by certain other confinement concepts (albeit to date at much poorer

temperatures and confinement parameters). However, physical phenomena in the plasma prevent

beta values from being increased indefinitely.

These phenomena, which differ from concept to

concept, are not completely understood; gaining additional understanding in this area is a high

priority.

Low beta values can also be compensated by

raising the magnetic field strength. Whereas raising beta primarily involves plasma physics issues,

the issues involved in raising the magnetic field

strength are primarily engineering-related: stronger

magnetic fields are more difficuIt and expensive

to generate and place greater stress on the magnet

structures. At some field strength, the advantages

of stronger magnetic fields will be outweighed

by the additional expense of the magnets.

Scaling.–Understanding how tokamak performance can be expected to improve is crucial

to evaluating the tokamak’s potential for future

reactors as well as to designing next-generation

tokamak experiments. As mentioned earlier, the

complete theoretical mechanism determining

tokamak scaling has yet to be understood. Observationally, plasma confinement has been found

to improve with increased plasma size. Empirical data also show that tokamak confinement improves when plasma density is increased, but that

this behavior holds only for ohmically heated

plasmas. Non-ohmically heated plasmas follow

what has come to be known as “L (Low) -mode”

scaling, in which confinement degrades as increasing amounts of external power are injected.

A few years ago, experiments on the German

Axisymmetric Divertor Experiment (ASDEX) discovered a mode of tokamak behavior described

by a more favorable scaling, labeled “H (High)-

mode. ” In this mode, performance even with

auxiliary heating behaved more like the original,

ohmically heated plasmas. However, H-mode

scaling could be achieved only with a particuIar

combination of device hardware and operating

conditions. Subsequently, additional work at

other tokamaks has broadened the range of conditions under which this more favorable behavior

can be found. The challenge to tokamak researchers is to obtain H-mode scaling in configu rations and operating regimes that are also con-
72 . Starpower: The U.S. and the International Quest for Fusion Energy

Photo credit: Commission of the European Communities

The ASDEX tokamak at the Max-Planck Institute for

Plasma Physics, Garching, Federal Republic

of Germany.

ducive to attaining reactor-like temperatures and

densities.

Reactor Design

Just as an automobile is much more than spark

plugs and cylinders, a fusion reactor will contain

In

many systems besides those that heat and confine the plasma. Fusion’s overall engineering feasibility will depend on supporting the fusion reaction, converting the power released into a more

usable form of energy, and ensuring operation

in a safe and environmentally acceptable manner. Developing and building these associated

systems and integrating them into a functional

whole will require a technological development

effort at least as impressive as the scientific

challenge of creating and understanding fusion

plasmas.

The following section describes the systems in

a fusion reactor. Since the tokamak confinement

concept and the D-T reaction are the most extensively studied, a tokamak-based reactor fueled

with D-T is used as an example. However, most

of the systems described here would be found,

in some form, in reactors based on other concepts as well.

The overall fusion generating station (figure 4-

10) consists of a fusion power core, containing

the systems that support and recover energy from

the fusion reaction, and the balance of plant that

converts this energy to electricity using equipFigure 4-10.—Systems in a Fusion Electric Generating Station

Rejected

heat

Fusion power core

inside

Balance of

plant -

Electric power

out to grid
Ch. 4.—Fusion Science and Technology “ 73

ment similar to that found in present electricity

generating stations. Features that might convert

fusion power to electricity more directly in advanced fusion reactors are described in a subsequent section.

Fusion Power Core

The fusion power core, shown schematically

in figure 4-11, is the heart of a fusion generating

station. It consists of the plasma chamber, the surrounding blanket and first wall systems that recover the fusion energy and breed tritium fuel,

the magnet coils generating the necessary magnetic fields, shields for the magnets, and the fueling, heating, and impurity control systems. Before an acceptable design for a fusion power core

can be developed, the behavior of fusion plasmas

must be understood under all conditions that

might be encountered. Furthermore, significant

Figure 4-11.—Systems in the Fusion Power Core

Electromagnetic

radiation

Neutrons

SOURCE.
74 . Starpower: The U.S. and the International Quest for Fusion Energy

advances must be made in plasrna technologies,

which confine and maintain the plasma, and nuc/ear technologies, which recover heat from the

plasma, breed fuel, and ensure safe operation.

Balance of Plant

Balance of plant generally describes the systems

of a fusion generating station outside of the fusion power core. In the example shown in figure 4-11, the balance-of-plant resembles systems

found in other types of electric generating stations. These systems use heat provided by the fusion core to produce steam that drives turbines

and generates electricity. The steam is cooled by

passing through the turbines, and the remaining

heat in the steam is exhausted through cooling

towers or similar mechanisms.

More advanced systems that convert plasma

energy directly into electricity also may be possible. Fusion reactors incorporating such systems

could be made more efficient than those using

steam generators and turbines.

FUSION POWER CORE SYSTEMS

The Fusion Plasma

At the center of a fusion reactor, literally and

figuratively, is the fusion plasma. A number of

supporting technology systems create and maintain the plasma conditions required for fusion reactions to occur. These technologies confine the

plasma, heat and fuel it, remove wastes and impurities, and, in some cases, drive electric currents within the plasma. They also recover heat,

breed fuel, and provide shielding.

Further development of many of these plasma

technologies is required before they will be capable of producing a reactor-scale plasma. Furthermore, each of these supporting systems affects plasma behavior, and the interactions are

incompletely understood. progress in both plasma

technology and plasma science is therefore

needed before reactor-scale fusion p

be created.

Heating

Description.–Some heat loss from

lasmas can

I a plasma

is inevitable (see box 4-A), but, with good confinement, the losses can be made up by external

heating and/or by fusion self-heating. Different

mechanisms for heating the plasma, illustrated

in figure 4-12, are listed below.

Ohmic Heating. -Like an electric heater, a

plasma will heat up when an electrical current

is passed through it. However, the hotter a

plasma gets, the better it conducts electricity and

therefore the harder it is to heat further. As a result, ohmic heating is not sufficient to reach ignition in many configurations.

Neutral Beam Heating. –Energetic charged or

neutral particles can be used to heat fusion

plasmas. However, the same magnetic fields that

prevent the plasma from escaping also prevent

charged particles on the outside from easily getting in. Therefore, beams of energetic neutral (uncharged) particles that can cross the field lines

are usually preferred for heating the plasma.

Radiofrequency Heating. -Electromagnetic radiation at specific frequencies can heat a plasma

like a microwave oven heats food. Radiofrequency

or microwave power beamed into a plasma at

the proper frequency is absorbed by particles in

the plasma. These particles transfer energy to the

rest of the plasma through collisions.

Compression Heating. –Increasing the confining magnetic fields can heat a plasma by compressing it. This technique has been used in tokamak devices and is one reason for studying the

field-reversed configuration confinement approach. As stated earlier, there is hope that compression may be sufficient to heat an FRC plasma

to ignition.

Fusion Self-Heating.–The products of a D-T fusion reaction are a helium nucleus—an alpha

particle–and a neutron. The neutron, carrying

most of the reaction energy, is electrically uncharged and escapes from the plasma without reacting further. The alpha particle, carrying the rest

of the energy from the fusion reaction, is charged

and remains trapped within the confining mag-
Ch. 4.—Fusion Science and Technology ● 7 5

Photo credit: GA Technologies Inc

View inside vacuum vessel of the D II I-D tokamak at GA Technologies, San Diego, California.

The plasma is contained within this vessel.

netic fields. Hundreds of times hotter than the gigahertz (billions of cycles per second), are unsurrounding plasma, the alpha particle heats der study. Each frequency range involves differother plasma particles through collisions. ent technologies for generation and transmission.

Status.– Recent system studies show that radiofrequency (RF) heating offers significant advantages over neutral beam heating. Consequently,

the U.S. neutral beam research program has been

reduced while the RF heating program has grown.

Various types of RF heating, using different frequencies of radiation from tens of megahertz (millions of cycles per second) to over a hundred

Issues.—Additional research and development

(R&D) in heating technologies is essential to meet

the needs of future experiments and reactors. Key

technical issues in RF heating are the development of sufficiently powerful sources of radiofrequency power (tens of megawatts), particularly

at higher frequencies, and the development of

launchers or antennas to transmit this power into
the plasma, particularly at lower frequencies.

Resolution of these issues will require technological development as well as improved understanding of the interaction between radio waves and

plasmas.

Since no ignited plasma has yet been produced,

the effects of fusion self-heating on plasma confinement and other plasma properties are not

experimentally known. Confinement could degrade, just as it does with other forms of auxiliary

heating. Although self-heating can be simulated

in some ways in non-ignited plasmas, its effects

can be fully studied only upon reaching high

energy gain or ignition. The ignition milestone,

therefore, is crucial to the fusion program, and

understanding the behavior of ignited plasmas is

one of the program’s highest scientific priorities.

Fueling

Description. –Any fusion reactor that operates

in pulses exceeding a few seconds in length must

be fueled to replace particles that escape the

plasma and, to a lesser extent, those that are consumed by fusion reactions. Firing pellets of frozen deuterium and tritium into the plasma currently appears to be the best approach for fueling.

Both pneumatic (compressed gas) and centrifugal

(sling) injectors have been used (figure 4-13).

Neutral beam fueling has been used in experiments, but fueling reactors in this way would take

excessive amounts of power.

Status.–Pellets up to 4 millimeters in diameter

have been fired into experimental plasmas at

speeds of up to 2 kilometers per second and at
Ch. 4.—Fusion Science and Technology . 77

Figure 4-12.—Plasma Heating Mechanisms

Radiofrequency

heating

hydrogen atoms Magnetic deflector

/ /

Hydrogen

ion

Neutralizer source

Neutral injection Accelerator

heating

SOURCE. Oak Ridge National Laboratory

repetition rates ofs to 40 pellets per second. U.S.

development of pellet fueling technology, centered at Oak Ridge National Laboratory, is well

ahead of fueling technology development elsewhere in the world. By building state-of-the-art

pellet injectors for use on foreign experiments,

the United States is able in return to gain access

to foreign experimental facilities.

Issues.—Reactor-scale plasmas will be denser,

hotter, and perhaps bigger than the plasmas made

o date in fusion experiments; moreover, reactor

pIasmas will contain energetic alpha particles. All

these factors will make it much more difficult for

pellets to penetrate reactor plasmas than plasmas

Photo credit: Princeton Plasma Physics Laboratory

made in present-day facilities. Penetration to the

center of the plasma, most desirable from a theoretical point of view, probably will be extremely

Princeton Large Torus at PPPL, showing waveguides difficult in reactor plasmas. Experiments are now

for the RF heating system. underway to understand how deeply a pellet
78 ● Starpower: The U.S. and the International Quest for Fusion Energy

Figure 4-13.—Centrifugal Pellet Injection

SOURCE: Oak Ridge National Laboratory

must penetrate. Tokamaks, for example, appear

to have a mechanism, not yet understood, that

transports fuel to the center of the plasma. Fuel

might be brought into the center more effectively

in some of the alternate confinement concepts

with turbulent plasmas, such as the reversed-field

pinch or the spheromak.

If deeper penetration is required than can now

be attained, either larger pellets or higher injection speeds will be needed. Larger pellets are not

difficult to produce, but they may disturb the

plasma too much; additional work needs to be

done to determine how fuel pellets affect plasma

behavior, If larger pellets cannot be used, higher

injection speed will be required, which is technologically much more difficult. Improving present techniques is unlikely to increase injection

speeds by more than about a factor of 2. New

techniques capable of producing much higher injection speeds are being investigated, but the

pellets themselves may not survive injection at
Ch. 4.—Fusion Science and Technology ● 7 9

these speeds due to fundamental limitations in

their mechanical properties.7

Current Drive

Description.–Several confinement concepts,

including the tokamak, require generation of an

electric current inside the plasma. In most present

experiments, this current is generated by a transformer. In a transformer, varying the electric current in one coil of wire generates a magnetic field

that changes with time. This field passes through

a nearby second coil of wire—or in this case the

conducting plasma—and generates an electric

current in that coil or plasma. Varying the magnetic field is essential; a constant magnetic field

cannot generate current.

in tokamak experiments, a coil located in the

“doughnut hole” in the center of the plasma

chamber serves as one coil of the transformer.

Passing a steadily increasing current through this

coil creates an increasing magnetic field, which

generates current in the plasma. When the current in the first coil levels off at its maximum

value, its magnetic field becomes constant, and

the current in the plasma peaks and then starts

to decay. If the fusion plasma requires a plasma

current, its pulse length is limited by the maximum magnetic field of the first coil and the length

of time taken for the plasma current to decay.8

Status.–Techniques are now being studied for

generating continuous plasma currents, rather

than pulsed ones, because steady-state reactors

are preferable to ones that operate i n puIses. g Injecting radiofrequency power or neutral beams

into the plasma might be able to generate such

steady-state currents in tokamaks. The injected

power or beams generate currents either by

7Argon ne National Laboratory, Fusion Power Program, Technica/ Planning Activity: Find/ Report, commissioned by the U.S. Department of Energy, Office of Fusion Energy, AN L/FPP-87-l, january 1987, p. 189.

81n tokamaks, this decay time can be thousands of seconds. For

confinement concepts with plasmas that are more resistive to electric currents, the decay time is shorter, on the order of hundreds

of seconds. Operating for periods of time longer than the decay

time requires non-transformer current drive mechanisms.

9Components in pulsed systems undergo periodic stresses not

experienced in steady-state systems. Pulsed reactors also require

some form of energy storage to ellminate variations in their electrical output.

“pushing” directly on electrons in the plasma or

by selectively heating particles traveling in one

direction. Experiments have confirmed the theory of radiofrequency current drive and have succeeded in sustaining tokamak current pulses for

several seconds.

Some other confinement concepts, such as the

reversed-field pinch or the spheromak, can generate plasma currents with small, periodic variations in the external magnetic fields. Such currentdrive technologies do not involve complex external systems.

Issues.–The principal issues involving steadystate current drive are cost and efficiency, especially under reactor conditions. I n particular, the

radiofrequency technique becomes less efficient

as the plasma density increases. This inefficiency

could pose problems because reactors will probably operate at higher densities to maximize generated power. At this time, it is not known whether

the efficiency of continuous current drive can

be increased to the point where it could replace

the pulsed transformers now used in tokamaks.

However, radiofrequency current drive might

also be used to augment the puIsed transformer

by starting up the plasma current in a period of

low-density operation. Once the plasma current

was started, the density could be raised and the

transformer used to sustain the current. The radiofrequency current drive together with the

transformer would be able to generate longer lasting pulses than the transformer alone.

Reaction Product and Impurity Control

Description .–Alpha particles, which build up

as reaction products in steady-state or very longpulse fusion reactors, will have to be removed

so that they do not lessen the output power by

diluting the fuel and increasing energy loss by radiation, Devices that collect ions at the plasma

edge can be used to remove alpha particles from

the plasma. Alpha particles, when combined with

electrons that are also collected at the plasma

edge, form helium gas that can be harmIessly released. Unburned fuel ions also will be collected;

these will be converted to deuterium and tritium

gas, which will have to be separated from the

helium and reinfected into the plasma.
80 ● Starpower: The U.S. and the International Quest for Fusion Energy

The same devices that collect ions at the plasma

edge help prevent impurities from entering the

plasma. Even small amounts of impurities can

cool the plasma by greatly accelerating the rate

at which energy is radiated away.

Status.–Two types of devices are being considered for these tasks: pumped limiters and

diverter-s. A limiter is a block of heat-resistant material that, when placed inside the reaction chamber, defines the plasma boundary by intercepting particles at the plasma edge. A variant, the

pumped limiter, combines a limiter with a vacuum

pump to remove the material collected by the

limiter. A divertor generates a particular magnetic

field configuration in which ions diffusing out of

the fusion plasma, as well as those knocked out

of the vessel walls and drifting towards the

plasma, are diverted away and collected by external plates.

Both limiters and diverters are in direct contact with the plasma edge. Although temperatures

at the edge are far below the 100-million-degree

C temperatures found in the plasma center, these

components will nevertheless get very hot. All

the energy injected into or produced by the

plasma that is not carried away by neutrons or

radiated away as electromagnetic energy is eventually deposited on the limiter or divertor plates

by electrons and ions. Therefore, these devices

must withstand high heat loads under energetic

ion and neutral particle bombardment while being exposed to intense neutron radiation. In a fusion environment, they will become radioactive

due to neutron-induced reactions and, to a much

lesser extent, to permeation with tritium. Their

reliability must be high since they will be located

deep within the reactor, inside the vacuum vessel, where maintenance will be difficult.

issues.–A key issue for reaction product and

impurity control will be the choice between

pumped limiters and diverters. The devices not

only have different efficiencies but have different effects on plasma confinement. Limiters are

simpler, but diverters may have operational advantages. 10 More R&D is necessary to investigate

issues such as the conditioning and cleaning of

surfaces in contact with the plasma, the erosion

of these surfaces and redeposition of their materials elsewhere in the plasma chamber, the effects of high heat loads, the development of cooling systems, and the degree and effects of tritium

permeation.

Burn Control

Description. —When a fusion reactor plasma

is ignited, it provides its own heat and no longer

depends on external heating. Two opposing tendencies make it difficult to determine how stable, or self-regulating, an ignited plasma will be.

An ignited plasma may be inherently unstable

due to the strong temperature dependence of the

fusion reaction rate. If, for whatever reason, a hot

spot forms in the plasma, the fusion reaction rate

there will go up. As a result, more fusion power

will be generated in that area, heating it further

and compounding the original problem.

If the plasma particles mix with sufficient speed,

hot spots that form will not persist long enough

to grow. If, on the other hand, the mixing is slow,

this thermal instability might make it very difficult to maintain a steady reaction. Formation and

growth of hot spots could cause output power

levels to fluctuate considerably, and in the worst

case these hot spots could grow until much of

the fuel present in the reaction chamber was consumed. The amount of fuel would not be large—

at most a few seconds’ worth-making this process more of an operational problem than a safety

one. The reactor would have to be designed so

that it could not be damaged, and its contents

not be released, by the maximum amount of

energy that could be produced in this way.

Countering this possible instability is a selfregulating mechanism that limits the maximum

attainable value of the beta parameter. Any instability that heated the plasma would increase

the plasma beta, which is proportional to temperature. However, since the power generated

by a fusion reactor is proportional to beta squared,

a reactor would probably already be operating

IOThe H.mode of tokamak operation, in which confinement properties are significantly improved, is seen in tokamaks with diverters. This mode, now thought to depend on processes occurring

at the plasma edge, may be difficult to reproduce with Iim iters.
Ch. 4.—Fusion Science and Technology ● 8 1

at the highest value of beta consistent with good

performance. Further increases in beta would degrade plasma confinement and increase energy

loss. These increased losses would cool the

plasma back down, counteracting the initial instabiIity.

These beta-limiting processes could maintain

a steady reactor power level. The plasma would

tend to operate just under the limiting beta value,

and, by adjusting the magnetic field or the plasma

density, the power level corresponding to the

limiting beta value could be controlled.

Status and Issues.– It is impossible, without

creating and studying an ignited plasma, to determine how a plasma will behave in the face of

the two opposing tendencies described above.

Neither the causes of beta-limiting processes nor

their effects on the plasma are fully understood

in general. More research is necessary before the

ability of these processes to stabilize a fusion

plasma can be determined.

The processes that control the reaction rate and

burn stability of an ignited plasma are probably

the most device-dependent and least understood

of any aspect of burning plasma behavior. 11 Even

for tokamaks, the properties that determine stability have been studied only under conditions

well short of ignition; still less is known about the

properties of other confinement concepts. If these

issues are indeed concept-specific, only limited

information from a burning plasma experiment

using one confinement concept can be used to

predict the behavior of another.

The Fusion Blanket and First Wall

The region immediately surrounding the fusion

plasma in a reactor is called the blanket; the part

of the blanket immediately facing the plasma is

called the first wall. In some designs, the first wall

is a separate structure; most often, however, the

first wall refers to the front portion of the blanket that may contain special cooling channels.

The blanket serves several functions. Cooling

systems in the blanket remove the heat generated by fusion reactions and transfer it to other

parts of the facility to generate electricity. Depending on plant design and materials selection,

these cooling systems also might be needed to

remove afterheat from the radioactive decay of

materials in the blanket after a plant shutdown.

In addition, the tritium fuel required by the reactor is produced, or “bred,” in the blanket. Furthermore, the blanket must support itself and any

other structures that are mounted on it.

The safety of the plant will be greatly influenced

by the blanket breeder, coolant, and other subsystems. Since the blanket will perform multiple

functions, its development will require an integrated R&D program. This program must have

two primary aspects: it must develop the capability to predict the behavior of blanket components and systems under actual reactor usage,

and it must develop technologies that can produce fuel and recover energy in the blanket while

maintaining attractive economic, safety, and environmental features.

Intense irradiation by neutrons produced in the

fusion plasma will make blanket components

radioactive, with the level of induced radioactivity

depending on the materials with which these

components are made. Tritium bred within the

blanket will add to the blanket’s total radioactive

inventory. As the largest repository of radioactive

materials in a fusion plant, the blanket will be the

focus of environmental and safety concerns.12

The discussion below focuses on blankets that

would be used in fusion reactors that generate

electricity. Reactors used for other purposes,

some of which are discussed in appendix A,

would have different blanket designs.

Description

Energy Conversion.–The first wall is heated

by radiation from the plasma as well as by energy

carried by particles leaking out of the plasma.

Energetic neutrons produced in the plasma penetrate the blanket, where they slow down and convert their kinetic energy into heat. coolant circuIating within the blanket and first wall transfers

this heat to other areas of the plant, where it is

I I Argonne Nat I. na I La t)orato ry, Technic,;/ P/arming ActI\It)’: F;-

na/ Report, op. cit., p. 155. I J plant safety characterlst ICS are d ISCU JSed tu rther I n ch. J
82 . Starpower: The U.S.. and the International Quest for Fusion Energy

used to generate electricity. The coolant also prevents blanket and first wall components from

overheating during reactor operation; depending on plant design, coolant also may be needed

to prevent overheating after plant shutdown,

whether scheduled or emergency. Depending on

the level of radioactivity within the blanket and

coolant, secondary heat exchangers like those

now used in nuclear fission plants may be required to isolate the coolant.

Fusion neutrons slow down by colliding with

the nuclei of blanket materials, transferring energy

to the blanket in the process. Additional heat is

also generated in reactions that occur when the

neutrons are captured by materials in the blanket. Depending on their energy, the neutrons

travel up to several centimeters between collisions. Collisions change the neutrons’ directions,

and a blanket thickness of from one-half meter

to one meter is enough to capture most of the

neutron energy.

Tritium Breeding.–Through reactions with fusion neutrons, the nuclei in the blanket can be

changed into other nuclei that are either stable

or radioactive. In particular, if a fusion neutron

is captured by a lithium nucleus, it will induce

a reaction that produces tritium (see box 4-B).1

3

Therefore, the presence of lithium in the blanket is necessary for tritium breeding.

The number of tritium nuclei produced in the

fusion blanket per tritium nucleus consumed in

the fusion plasma, called the breeding ratio, must

be at least 1 for the reactor to be self-sufficient

in tritium supply. Accounting for losses and imperfections in the blanket, as well as uncertainties in the data used to calculate tritium breeding rates, this ratio probably should be in the

range of 1.1 to 1.2.

Lithium can be contained in the blanket in either solid or liquid form. Lithium metal has a low

melting point (186 o C) and excellent heat transfer properties, making it attractive as a coolant

in addition to its use in breeding tritium. However, in its pure form, liquid lithium can be highly

1 JLithium is a reactive metal that does not occur in its pure form

in nature. However, chemical compounds containing lithium are

found in many minerals and in the waters of many mineral springs.

Fuel resources for fusion are discussed in ch. 5.

reactive and may pose safety problems i n fusion

reactors. Liquid lithium’s reactivity can be lessened by alloying it with molten lead, but the

addition of lead substantially increases the production of undesired radioactive materials in the

blanket.

Liquid metal coolants can be avoided by separating the function of cooling the blanket from

that of breeding tritium. A non-lithium-containing

fluid can be used as the coolant, and solid lithium-containing compounds can be used to produce tritium. However, solid lithium compounds

contain other elements, such as oxygen and aluminum, that would capture some of the fusion

neutrons and lower the breeding ratio. To com-
Ch. 4.—Fusion Science and Technology ● 8 3

pensate for the lost neutrons, substances called

neutron rnultipliers can be added to the blanket.

Neutron multipliers convert one very fast fusion

neutron to two or more slower neutrons by

means of a nuclear reaction.

Recovering the tritium from solid breeder materials is more difficult than from liquid breeders.

When tritium is bred in a liquid coolant, the coolant carries the tritium directly outside the blanket where it can be extracted. Tritium produced

in solid lithium-containing compounds, on the

other hand, must first diffuse out of those compounds before it can be collected and flushed

out of the blanket by a circulating stream of

helium gas.

Blanket Structure.—The heat loads, neutron

fluxes, and radiation levels found in the blanket

place stringent requirements on the materials

with which the blanket is made. Conditions are

most severe at the first wall, which is bombarded

by neutron and electromagnetic radiation from

the plasma, by neutral particles, and by plasma

electrons and ions that escape confinement. First

wall issues are similar to many of the issues associated with limiters and diverters (discussed previously in the section on “The Fusion Plasma, ”

under the heading “Reaction Products and impurity Control”), which undergo even higher heat

and particle fluxes than the first wall.

Neutron irradiation introduces two major problems in the blanket materials. First, irradiation can

lead to brittleness, swelling, and deformation of

the reactor structural materials. During the service lives of first wall and blanket components,

each atom in those components will be displaced

several hundred times by collisions with fusion

neutrons. The amount of radiation damage that

the blanket materials can withstand determines

component lifetimes and also places an upper

limit on reactor power for a blanket of a given

size.

Second, neutron irradiation makes the blanket

radioactive. Not all the neutrons penetrating the

blanket will be captured in lithium to breed

tritium, Some will be absorbed by other blanket

materials, making those materials radioactive.

I J BerylI I u m ~ ncj lead are common Iy used I n rea~to r stud I es Js

neutron mu Itlpliers,

Other fusion neutrons will penetrate the blanket

to make reactor structures outside the blanket

radioactive. Since the degree of radioactivity generated within the reactor structure strongly depends on the reactor’s composition, development and use of /ow-activation materials that do

not generate long-lived radioactive products

under neutron bombardment will greatly lessen

induced radioactivity,

Due to radiation damage, blanket and first wall

components in a fusion reactor wil I require periodic replacement. After their removal, the old

components will constitute a source of radioactive waste. ’ 5

Impact on Fusion Reactor Design .–Although

the blanket and first wall components themselves

may not represent a large fraction of the cost of

a fusion reactor, blanket design has a substantial influence on total reactor cost. The blanket

thickness (along with that of the shield, described

below) determines the size and cost of the magnets, which are substantially more expensive than

the blanket. The blanket coolant temperature determines the overall efficiency with which the

plant converts fusion power into electricity, directly affecting the cost of electricity. The selection of materials in the blanket determines the

amount of long-term radioactive waste and the

amount of heat produced by radioactive decay

in the blanket after plant shutdown; both the

waste and the heat affect the reactor’s environmental and safety aspects. Finally, the ability of

the blanket materials to withstand heat loads and

neutron irradiation levels determines the amount

of fusion power that can be generated in a plant

of a given physical size, which has a significant

effect on reactor size and cost and on its behavior

during accidents.

Status and Issues

A wide variety of designs have been proposed

for the blanket and first wall. However, since the

1 sAccord ! ng to Argonne National Laboratory, Technical P/.lnn/nL~

Acti\ity: F/na/ Repor?, op. cit., p. 283, the amount ot long-l{~ed

(more than 5 years) radioactive waste depends primarily on the

amounts of copper, molybcien u m, nitrogen, niobium, and nickel

used In the blanket. Radioacti\lty levels, radioactive wastes from

fusion reactors, and Iow-activation materials are discussed tu rther

In ch. 5.
84 . Starpower: The U.S. and the International Quest for Fusion Energy

fusion research program has concentrated to date

primarily on plasma science issues, relatively little experimental work has been done on blanket design or fusion nuclear technologies in general. As the program moves from establishing

scientific feasibility to demonstrating engineering

feasibility, engineering issues will become much

more important.

Tritium Self-Sufficiency .-Engineering designs

must be developed to produce tritium at a rate

equal to the rate of consumption in the plasma

plus an additional margin, The extra tritium, 10

to 20 percent of the amount consumed in the

plasma, is needed to compensate for losses due

to radioactive decay and to provide the initial inventory to start up new reactors. Improvements

in calculating neutron flow through the reactor

structure and in collecting additional basic nuclear data such as reaction rates are necessary

to develop adequate engineering designs. Experimental verification of the calculation methods

and data is also required to demonstrate tritium

self-sufficiency.

Structural Materials.–Structural materials in

the first wall and deeper in the blanket must be

developed that can withstand neutron-induced

effects such as swelling, brittleness, and deformation. Stainless steel alloys already have been

identified that appear to show adequate performance under neutron fluxes at the low end of those

expected in a reactor. However, these materials

produce more radioactive products than may be

desirable for commercial reactors. Developing

low-activation materials that also have acceptable

physical properties under irradiation remains a

significant challenge. The task will require further

basic research in materials science as well as

progress in materials technology.

Non-Structural Blanket Materials.–The tritiumbreeding properties of various lithium-containing

materials must be studied and compared. The

choice between solid and liquid breeder materials, in particular, will greatly affect overall blanket design. in addition to lithium, other materials may be required in the blanket such as

neutron multipliers and moderators (which slow

down neutrons to make them more easily absorbed in the blanket). Insulators, or materials that

do not conduct electricity, also maybe required

for high radiation areas inside the reactor. Since

a typical effect of radiation damage on insulators

is to increase electrical conductivity, developing

materials that will remain insulators under high

radiation fluxes is a challenging task.

Special Materials.–Other materials requirements for a fusion reactor may include special

materials to coat plasma-facing surfaces to minimize their effect on the plasma, coatings or claddings used to form barriers to contain tritium, and

advanced superconducting magnet materials (described in the section on magnets, below). Many

of the specific requirements for these materials

have not yet been determined.

Compatibility.–Certain combinations of materials, each suitable for a particular task, may in

combination prove unacceptable in a reactor design. For example, liquid lithium reacts violently

with water, so a liquid lithium-cooled blanket design would probably prohibit use of water as an

additional coolant.

Tritium Permeation and Recovery.–Once produced inside the blanket, tritium must be recovered and removed. However, tritium will permeate many materials that are continuously exposed

to it. Its interactions with blanket materials under the conditions inside a fusion reactor will

have to be understood. In particular, tritium may

be difficult to collect from solid breeder materials.

Liquid Metal Flow.—Liquid metal coolants in

a fusion reactor will be subject to strong magnetic

fields created both by the plasma and by external magnets. Liquid metals are conductors of

electricity; when electrical conductors move

through magnetic fields, voltages and currents are

generated.16 The currents induced in the coolant, in turn, are subject to forces from the magnetic field that oppose the motion of the coolant, increasing coolant pressure and adding to

the power required for pumping.

The Shield

Description and Status

Since many neutrons will penetrate all the way

through the blanket during fusion reactor operIGThis process IS the basis of electrical generators.
Ch. 4.—Fusion Science and Technology ● 8 5

ation, a shield may be required between the blanket and the magnet coils.17 The shield may be

composed of materials such as steel and water,

will probably contain a circulating coolant, and

would have a thickness from tens of centimeters

to over a meter. The shield would provide extra

protection to the magnets and could reflect escaping neutrons back into the blanket to improve

the efficiency of tritium breeding. Additional

shielding wouId probably surround the entire reactor core, perhaps in the form of thick walls for

the enclosing building.

Most existing fusion experiments have not been

designed to use tritium and are incapable of generating significant amounts of fusion power. Consequently, shielding has generally not been an

important issue for the research program. It has,

however, been a factor in the design of devices

such as TFTR and the Joint European Torus that

are intended to use tritium. As future machines

are designed that will generate appreciable amounts

of fusion power, shielding will become more important.

Issues

The intensity of the incident neutron radiation;

the size, shape, and effectiveness of the shield;

and the permissible levels of neutron irradiation

penetrating the shield must all be determined to

evaluate shielding requirements. As improved

magnet materials are developed that are less sensitive to neutron radiation, shielding requirements

for plant components will lessen. However, protection of plant personnel alone will require substantial shielding.

The Magnets

Description

The external confining magnetic fields in a fusion reactor are generated by large electric currents flowing through magnet coils surrounding

the plasma. These magnets must withstand tremendous mechanical forces,

.. —-—-—. .

I Plf the magnets are superconducting, the shield will be requl red.

If they are made of copper, the shield may not be necessary. However, without a shield, the coils would require periodic replacement. See the following section on magnets.

The most important choice concerning design

of the magnets is whether they will be made of

superconducting materials or of conventional

conductors such as copper. Copper is an excellent conductor of electricity but nevertheless has

sufficient resistance to electric currents that a

great deal of power is wasted as heat when the

magnet is running. This heat must be removed

by cooling systems. Superconducting coils lose

all resistance to electricity when cooled sufficiently; below a temperature called the critical

temperature, their magnetic fields can be sustained without any additional power. However,

power is required to establish the fields initially,

and a small amount of refrigeration power is required to keep superconducting magnets at their

operating temperature. No heat is generated inside a superconducting magnet, but heat that

leaks in from the outside must be removed.

Although recent discoveries could revolutionize the field (see “issues” section below), all superconducting materials that have so far been

used in large magnets have critical temperatures

within about 20° K of absolute zero. The only

substance that does not freeze solid at these temperatures is helium, and the only way to cool superconducting magnets to these temperatures is

to circulate liquid helium through them. Use of

liquid helium makes superconducting magnets

more complicated and expensive to build than

copper magnets; superconducting magnets also

require thicker shields. However, superconducting magnets require much less electricity to run,

substantially lowering their operating costs.

Conceptual design studies typically have shown

that the operational savings from using superconducting magnets in commercial fusion reactors

would more than compensate for their higher initial cost. However, there may be exceptions,

especially for confinement concepts with higher

beta values that are able to confine fusion plasmas

at lower magnetic field strengths. At lower field

strengths, copper magnets, which do not require

as much shielding as superconducting magnets,

can be made to fit more closely around the

plasma chamber. The resultant reduction in size

of the magnet/shield combination might reduce

its cost enough to outweigh the operational inefficiencies of copper magnets.
86 . Starpower: The U.S. and the International Quest for Fusion Energy

Whereas the magnets in future fusion reactors

will operate for long pulses, if not continuously,

magnets in present-day fusion experimental facilities generally operate only for several seconds

at a time. For pulses this short, the cost of electricity is less of a factor in determining magnet

design, making the simpler construction of copper magnets preferable in most cases. A notable

exception is the MFTF-B device at Lawrence Livermore National Laboratory, which was built with

superconducting magnets because copper coils

would have been prohibitively expensive to operate even for 30-second puIses.

Status

The first fusion device built with superconducting magnets was the Soviet T-7 tokamak, completed 7 years before any Western fusion device

using superconducting magnets. The Soviets are

now building T-1 5, a much larger superconducting tokamak. Difficulties with the T-1 5 magnets

have been among the reasons that the project’s

completion has been delayed for several years;

however, these difficulties apparently have been

resolved. The Tore Supra tokamak being built in

France will also use superconducting magnets

and will probably exceed the parameters of T15.18 In the United States, MFTF-B was completed

in 1986; its superconducting magnets have been

successfuIly tested at their operating conditions.

Overall, DOE considers U.S. magnet development to be comparable to that in Europe and Japan and ahead of that in the Soviet Union.19

Generally, magnet development has been associated with individual fusion confinement experiments rather than with facilities dedicated specifically to magnet development. A major exception

is the Large Coil Task, an international program

to build and test superconducting magnets. Magnets developed through the Large Coil Task have

161 nformation on Soviet tokamak development IS from an oral

presentation on “Assessment of Soviet Magnetic Fusion Research”

by Ronald C. Davidson, Director of the Plasma Fusion Center, Massachusetts Institute of Technology, to the Magnetic Fusion Advisory Committee, Princeton, Nj, May 19, 1987.

l~lnternational comparisons are from a presentation by R.J. Dowling, Director of the Division of Development and Technology, Office of Fusion Energy, U.S. Department of Energy, to the Energy

Research Advisory Board, Sub-Panel on Magnetic Fusion, Washington, DC, May 29, 1986.

worked very well and have exceeded their original design specifications. 20

Issues

Recent discovery of new superconducting materials with critical temperatures far above those

of previously known materials, and possibly with

the capability to reach very high magnetic field

strengths, will have a profound impact on a great

many fields, including fusion. Materials have been

identified with critical temperatures higher than

the 77 Kelvin (–196° C) threshold that would

permit use of liquid nitrogen as a refrigerant. Liquid nitrogen is cheaper and easier to handle than

liquid helium, and its use could reduce the cost

and complexity of superconducting magnets.

However, the discovery of these “high-temperature’ superconductors does not necessarily

mean that they can soon be utilized in fusion applications. Little is known about the physical

processes underlying superconductivity in these

materials, and they present great engineering

challenges. They are difficult to fabricate into

magnet coils, and they may not be able to withstand the forces exerted in fusion magnets. Although their current-carrying capability is improving, they may not be able to carry high enough

currents under high magnetic fields to be useful

in large-scale magnets. Moreover, their response

to neutron irradiation is not known. If these materials are highly susceptible to radiation damage,

their use in fusion magnets could be difficult.

Conversely, if they proved more resistant to radiation effects than previous superconducting

materials, thinner shields and correspondingly

smaller magnets could be used.

Further research is required to see whether the

new superconducting materials can be used in

practical applications. The great economic advantage that they would have in numerous applications ensures that much of this research will be

undertaken independently of the fusion program.

However, fusion does have particular requirements for large, high-field magnets that may not

otherwise be investigated.

zOThe Large Coi I Task is discussed further in ch. 7.
Ch. 4.—Fusion Science and Technology ● 8 7

 - . 3
88 . Starpower: The U.S. and the International Quest for Fusion Energy

Issues for superconducting fusion magnet materials include further development and investigation of the new high-temperature materials. If

these new materials prove unacceptable for fusion, improvements in the strength, workability,

and maximum current capacity of the previously

known superconductors will be important. Issues

for copper magnets include fully exploiting copper’s strength and developing joints (needed to

assemble and maintain the magnet) that can carry

large electric currents.

Fuel Processing

Description

Tritium fuel contained in the exhaust from the

plasma, or generated in the reactor blanket, must

be extracted, purified, and supplied back to the

fueling systems for injection into the plasma. Considerable experience has been developed in handling tritium, particularly within the nuclear weapons program, making tritium technology more

highly developed than many of the other nuclear

technologies required for fusion. However, this

experience is applicable primarily to handling the

tritium in a fusion reactor once it has been

produced and separated. The task of extracting

tritium from a blanket under reactor conditions

while at the same time generating electric power

with high efficiency has yet to be done.

Status

To acquire experience with tritium handling for

fusion applications, DOE has built and is operating the Tritium Systems Test Assembly (TSTA) at

Los Alamos National Laboratory. A prototype of

the tritium processing and handling facilities

needed for a full-scale fusion reactor, TSTA includes plant safety equipment such as a room

atmosphere detritiation system. TSTA operators

have developed system maintenance procedures

that minimize or eliminate tritium release. This

system, however, does not duplicate the production or extraction of tritium from a fusion blanket.

Issues

Specific issues involved with tritium processing include monitoring, accountability, and safety.

Being radioactive, tritium cannot be allowed to

diffuse out of the reactor structure. if tritium collects on inaccessible surfaces within the reactor,

it cannot be completely recovered, and it will

make those surfaces radioactive. Developing tritium processing systems will require additional research in measuring basic tritium properties such

as diffusivity, volubility, and oxidation chemistry.

Safety needs include developing and maintaining the capability to contain and recover tritium

from air and from water coolants (if any) in the

event of tritium contamination.

Remote Maintenance

Due to their inventory of radioactive tritium

and the activation of their structural components,

the interior of all subsequent fusion experiments

that burn D-T will become too radioactive for

hands-on maintenance. Therefore, remote maintenance is a key issue not only for future power

reactors, but also for near-term D-T experiments.

Nearly all aspects of the research program, from

design of experiments to operation and maintenance to decommissioning, will be affected by

the need for remote maintenance.
Ch. 4.–Fusion Science and Technology “ 89

Photo credit Oak Ridge National Laboratory

The Swiss superconducting magnet coil being installed in the International Fusion Superconducting Magnet Test Facility

(Large Coil Task) at Oak Ridge National Laboratory.

The fusion program at present is relying on tenance requirements for fusion facilities will inactivities outside the fusion community for gen- clude transporters able to move heavy loads (over

eral development of remote maintenance equip- 100 tons) with precision alignment; manipulators

ment. Much work in remote manipulation and made of nonmagnetic material that can operate

remote maintenance has been done, but some under high vacuum conditions; and rapid and

applications are likely to be unique to fusion and precise remote cutting, welding, and leak detecwill require special development. Remote main- tion equipment. The first challenge in this field
90 “ Starpower: The U.S. and the International Quest for Fusion Energy

Photo credit: Los Alamos National Laboratory

The Tritium Systems Test Assembly at Los Alamos National Laboratory

will be identification of the remote maintenance quently, needs for test facilities and reactors must

requirements for near-term facilities and the de- be identified and assessed.

velopment of any necessary equipment. SubseADVANCED FUEL AND ENERGY CONVERSION CONCEPTS

Even though the fusion power core systems described in the previous section have not yet been

developed, researchers already are designing reactors using more advanced concepts. Improvements described below are not mere refinements

of the systems already described; they are qualitatively new features that may be much more attractive. In general, these improvements involve

use of either advanced fuels or advanced methods of converting fusion energy into useful forms.

Advanced Fuels

The fusion power core described in the previous section uses D-T fuel because it is by far the

most reactive of all potential fusion fuels. This

reactivity can be increased still further by aligning the internal spins of the deuterium and tritium

nuclei, a technique known as spin polarization.

If the spins can be aligned initially, the magnetic

field of the fusion reactor will tend to keep them
Ch. 4.—Fusion Science and Technology ● 9 1

in alignment. Therefore, research is ongoing at

Princeton Plasma Physics Laboratory to develop

intense sources of spin-polarized fuel.

The principal disadvantage of D-T fuel is that

the D-T reaction produces energetic neutrons that

cause radiation damage and induce radioactivity in reactor structures. Moreover, reactors using

D-T must breed their own tritium, substantially

adding to reactor complexity and radioactivity

levels. For these reasons, the possibility of using

other fuels in fusion reactors is being investigated.

Fuels other than D-T require higher temperatures and Lawson confinement parameters to

reach ignition and higher beta values to perform

economically. Achieving these parameters will require stronger magnetic fields, higher plasma currents, and substantial improvements in other

plasma technologies beyond those needed to

reach ignition with D-T fuel—a task that in itself

has not yet been accomplished. However, reactions that use advanced fuels would have a

number of advantages:

c They wouId require little to no tritium, reducing or eliminating the need for the blanket to breed tritium and permitting a much

wider range of blanket designs. Tritium inventories would be smaller and the consequent radioactivity levels would be lower.

● They would generate fewer and lower energy

neutrons, alleviating radiation damage and

minimizing radioactive wastes.

● They might permit the use of more efficient

methods to generate electricity from fusion

energy. I n advanced fuel fusion reactions,

more energy is released i n the form of energetic charged particles, such as protons or

alpha particles, than is the case in the D-T

reaction. Therefore, these advanced fuels

may be amenable to various techniques that

generate electricity directly from the fusion

plasma or from plasma-generated radiation

without having to first convert the energy

into heat. (See the following section on “Advanced Energy Conversion.”)

Table 4-8 presents five fusion fuel cycles, including the “baseline” D-T cycle and four possibilities for advanced fuel cycles. Of the advanced

cycles, the D-3He cycle is currently drawing the

most attention within the fusion community. The

primary reaction produces no neutrons, and neutrons resulting from corollary D-D reactions can

be minimized by using a mixture consisting mostly

of 3He or by using spin-polarization. 21

ZI Deuterium, being relatively scarce i n a 3He -rich mixture, would

be much more likely to react with a 3He nucleus than with another

deuterium nucleus, making D-D reactions relatively rare. However,

one consequence of this mode ot operation, in addition to minimizing neutron generation, wou Id be the lessening of output power

since most of the 3He nuclei would be unable to find D nuclel with

which to react. Increasing the ratio of D to ‘He to more nearly equal

proportions, theretore, would increase both the output power and

the neutron generation.

Spin polarization suppresses the D-D reaction rate because, unlike the D-T reaction, two deuterium nuclel whose spins are allgned

are Jess likely to react with each other,

Table 4-8.—Fusion Fuel Cyclesa
92 ● Starpower: The U.S. and the International Quest for Fusion Energy

However, the D-3He reaction is much more difficult to start than the D-T reaction. The minimum

temperature required to ignite D-3He is several

times higher than that needed for D-T; the minimum confinement parameter is about 10 times

higher. Given that the requirements for igniting

D-T have not yet been experimentally achieved,

attaining conditions sufficient to ignite D- 3He is

considerably farther off. On top of its technological requirements,

3

H e is scarce. It is an isotop e

of helium with one fewer neutron than natural

helium (4He), and it occurs on earth only as the

end-product of tritium decay. The only way to

collect 3He is to make tritium and wait for it to

decay or to breed 3He as the product of another

advanced fuel fusion reaction, the D-D reaction.

Due to the scarcity of 3He, the D-3He reaction

has been considered primarily an academic curiosity until recently.

Today, a resurgence of excitement about 3He

comes with the discovery that it is found in substantial amounts in the uppermost layers of soil

on the moon. Analysis of moon rocks brought

back by the Apollo missions shows that 3H e,

which is constantly emitted by the sun and carried by the solar wind, is deposited and retained

in the lunar surface. In principle, a rocket with

the cargo volume of the space shuttle could carry

back enough liquid 3He to generate all the electricity now used in the United States in one year.

Of course, the technology to recover 3He from

the moon would not be available for decades,

and the energy and capital investment required

to mine, refine, liquefy, and transport the 3H e

have yet to be evaluated.22

Advanced Energy Conversion

Despite the very high-level technology in the

fusion core, a baseline fusion reactor would generate electricity in much the same way that present-day fossil fuel and nuclear fission powerplants

do. Heat produced in the reactor would be used

to boil water into steam, which would pass through

turbines to drive generators. Through this process, about 35 to 40 percent of the energy produced in the fusion reaction would be converted

————

~~Use of lunar ‘He is discussed in “Lunar Source ot ‘He for Commercial Fusion Power, ” by L.J. Wittenberg, J.F, Santarius, and G.L

Kulclnski, Fus/on Technology 10(2): 167, 1986.

into electricity, with the remainder discharged as

waste heat. This efficiency, roughly the same as

that of fossil fuel and nuclear fission generating

stations, is determined primarily by the process

of generating electricity from the energy in the

steam. Efficiency could be raised if advanced,

high temperature materials in the blanket and first

wall of a fusion reactor permitted higher coolant

temperatures to be used.

If the intermediate step of heating steam could

be bypassed, a higher percentage of the energy

released in fusion reactions couId be converted

into electricity. Several techniques to integrate

generation of electricity directly into the fusion

power core have been conceived. One of these,

applicable to D-T reactors as well as to advanced

fuel reactors, would convert energy carried off

by escaping charged particles directly to electricity by collecting the particles on plates. This

technique is most applicable to open confinement concepts, in which charged particles can

be allowed to escape along magnetic field lines.

Other techniques, which can work with closed

confinement concepts, require plasma temperatures significantly higher than the 10- to 15-

kiloelectron-volt D-T ignition temperatures. Very

hot plasmas radiate more energy away in the form

of microwave radiation than cooler plasmas do,23

and it appears that this radiation could be captured at the first wall or in the blanket and converted directly into electricity. These “direct conversion” techniques would be better suited to

advanced fuels, which not only burn at higher

temperatures than D-T but also produce most of

their energy in the form of energetic charged particles. Unlike neutrons, which escape from the

plasma without heating it, charged particles are

retained within the plasma. The D-T reaction, in

which only 20 percent of the energy is given to

charged particles, is less suitable for techniques

that recover energy directly from the plasma.

Several direct conversion techniques that may

convert well over 35 percent of the fusion energy

to electricity have been identified. Until they can

be tested experimentally under conditions similar to those in an advanced fusion reactor, they

must be considered speculative. Nevertheless,

they provide a tantalizing goal.

J ‘See Item 2 In box 4-A, ‘ ‘Plasma Energy Lo\s Mec hanisnl~ ‘‘
Ch. 4.—Fusion Science and Technology ● 9 3

RESEARCH PROGRESS AND FUTURE DIRECTIONS

In 35 years of fusion research, the technological requirements for designing a fusion reactor

have become clearer, and considerable progress

has been made towards meeting them. Improved

understanding, based on both experiments and

increased computational ability, is providing

much of the predictive capability needed to design, and eventually to optimize, future plasma

experiments and fusion reactors.

Major advances in plasma research have been

made possible by progress in tokamak plasma

technologies:

. By the 1960s, experiments demonstrated the

crucial importance of attaining high vacuum

and low impurity levels in the plasma to

achieve high densities, temperatures, and

confinement times.

● In the mid-197os, neutral beam technology

was first used to heat plasmas to temperatures several times higher than those previously attained. High-performance, high-field

copper magnets were used to obtain high

Lawson confinement parameters in compact

tokamak plasmas.

● The development in the late 1970s of pellet

injectors to fuel plasma discharges led to further advances in plasma density and confinement. Development of the poloidal divertor

at about the same time led to the discovery

of the “H-mode,” a mode of tokamak behavior that was not subject to degraded confinement when auxiliary heating was used.

● I n the early 1980s, advances in high-power

radiofrequency technology gave experimenters

new tools to modify the temperature, current, and density distributions within the

plasma. Much of this new capability has yet

to be exploited.

These accomplishments have contributed to

the steady progress in plasma parameters plotted in figure 4-14. Figure 4-14(a) shows the product of the temperature, density, and confinement

time that has been achieved simultaneously in

various experiments over the last 20 years. Since

all three of these parameters must be high simultaneously for the product to be high, this product provides a rough measure of how well these

three requirements have been simultaneously

achieved.

The next figure, 4-1 4(b), plots the temperature

alone and compares it to the minimum temperature below which neither breakeven nor ignition can occur no matter how high the density

and confinement time. The TFTR point shows

temperatures well into the reactor regime and far

above that needed for ignition. However, the fact

that the corresponding TFTR point in figure 4-

14(a) is below the ignition threshold indicates that

high temperature is not sufficient; the product of

density and confinement time must also be high

for ignition.

Figure 4-1 4(c) shows progress in the parameter beta, the ratio of plasma pressure to magnetic

field pressure. Note that devices that have achieved

high values on one of the three plots often have

not been the ones that have gotten the highest

values in others. Future devices will have to

achieve high values in all areas simultaneously.

The Technical Planning Activity

The technological issues to be resolved betore

fusion’s potential as a power producer can be

assessed have been examined in detail in the

Technical Planning Activity (TPA), an analysis

commissioned by DOE’s Office of Fusion Energy

and coordinated by Argonne National Laboratory. 24 Over 50 scientists and engineers from the

fusion community identified and analyzed the

tasks and milestones that constitute the research

needed to reach the goal of the DOE fusion program: the establishment of the “scientific and

technological base required to carry out an assessment of the economic and environmental aspects

of fusion energy. ”25 According to DOE’s assignment to TPA, the assessment of fusion wouId be

culminated by the construction and operation of

“one or more integrated fusion faciIities . . . in

the post 2000 period. ”26

24 Argon “e N~tl~nc~ I L~bratc)ry, ~6Thf7;cd/ P/JfJfllf7~ Acfll 1~)”” ‘/-

nc7/ Report, op. cit.

251 bid., “Technical Pl~nnlng Acti\ @ Mlsslon Statement, ” p. 348

‘blblci.
94 “ Starpower: The U.S. and the International Quest for Fusion Energy

A)

Figure 4-14.-Progress in Tokamak Parameters

20

10

5

0.5

0.2

0.1

B)

6

1965 1970 1975 1980 1985 1990 1965 1970 1975 1980 1985 1990

Year

5

2

1970 1975 1980 1985 1990

The nature of an integrated fusion facility is not

specified by either DOE or TPA. The TPA report

describes it only as “the beginning of the commercialization phase of fusion” that could “perhaps” take the form of a demonstration power

reactor. 27 The decision to proceed with an integrated facility is scheduled in the TPA report

in the year 2005.

Key Technical Issues and Facilities

DOE defines four “key technical issues” that

must be resolved: magnetic confinement systems,

zTlbid., p. 26. On p. 11 of the TPA report, table S.2 provides “representative goals” for an integrated fusion facility (IFF) and for a

commercial power reactor. Comparing the two sets of goals shows

that the IFF falls well short of commercial performance. h would

only produce from one-sixth to one-third the heat generated by

a commercial-scale reactor, and it would have considerably lower

availability and shorter lifetime than a commercial plant. The IFF

described by these parameters, therefore, could not be considered

to be a “demonstration” power reactor.

properties of burning plasmas, fusion materials,

and fusion nuclear technology .18 For each of

these issues, TPA set technical goals and determined requirements for facilities that could reach

these goals.

Magnetic Confinement Systems

The key issue in confinement systems is the development of confinement concepts that would

be suitable for commercial fusion reactors. Progress here will require that a series of facilities be

built for whichever concepts are judged worthy

of further development. A preliminary experiment that investigates basic characteristics of a

new concept can be done for a few million dollars or less. An experiment that looks promising

can be followed up by a larger “proof-of-conw .s. @partrnent of Energy, Office of Energy Research, Magnetic Fusion Program P/an, DOE/ER-0214, February 1985, p. 6.
Ch. 4.—Fusion Science and Technology ● 9 5

cept” experiment, costing up to tens of millions

of dollars; such a device would explore the scaling properties of the concept and determine

whether it offers the potential for extrapolation

to a reactor.

If the results are promising, a “proof-of-principle” experiment would then be required to provide confidence that the concept could be scaled

up to reactor-level conditions. The JET, TFTR, and

JT-60 tokamaks are in this category. They are not

themselves reactor-level devices, but they will enable decisions to be made about whether to proceed to the final stage of concept development:

demonstration of reactor-level plasma conditions,

including fueling, burn control, ash removal, and

other functions necessary for reactor operation.

No reactor-level devices have yet been built for

any concept, including the tokamak.

Cost is very difficult to estimate for a future

proof-of-principle or reactor-level device. The

TPA report estimates costs ranging from 100 miiIion to several hundred million dollars or more.29

The costs of the existing JET, TFTR, and JT-60 devices range between $600 million and $950 million dollars,30 but these devices perform many

functions in addition to proof-of-principle for the

tokamak concept. There is no reason to think that

proof-of-principle devices for other confinement

concepts would be as expensive. A reactor-scale

device for a particular concept would have more

stringent technical requirements than its proofof-principle device and presumably would be

more expensive. However, the cost of a reactorIevel device depends on whether it would serve

other functions such as the long-pulse burn, nuclear technology demonstration, or system integration functions discussed below.

In addition to generic device requirements for

selected alternate confinement concepts, TPA

also set a requirement for additional tokamaks

to investigate features such as shaped plasmas (to

29 Argonne National Laboratory, Technical P/arming Activ;tY: Final Report, op. cit., table S. 12, p. 44 and table S. 16, p. 48.

JOU .s, Congress, House Committee on Science and Technology,

Task Force on Science Policy, Science Policy Study Background

Report No. 4: World Inventory of “Big Science” Research lnstrurnents and Facilities, Serial DD, prepared by the Congressional Research Service, Library of Congress, 99th Cong., 2d sess., December 1986, pp. 111, 121, and 127.

follow up on the PBX-M and D II I-D results discussed in the earlier sections “Advanced Tokamak, ” p. 59, and “Beta,” p. 70), steady-state

tokamak operation, and high-magnetic-field approaches to tokamak confinement.31

Properties of Burning Plasmas

Some of the most critical scientific issues yet

to be resolved in the fusion program involve the

behavior of ignited, or burning, plasmas. These

issues include the effects of self-heating on confinement and the effects of energetic alpha particles on plasma stability, burn control, and fueling.

Effects such as these, which existing experiments

cannot yet address, can profoundly influence fusion’s feasibility. TFTR may be able to provide

some information about the effects of alpha particle generation if it attains near-breakeven conditions in D-T operation. However, TFTR does

not have the capability to reach ignition and

therefore will not be able to resolve burning

plasma issues definitively. The European JET device should also have the capability to reach and

perhaps exceed breakeven, but it too will not be

able to resolve many of the burning plasma

issues.

According to TPA, two different tasks are required to study burning plasma issues fully. One

is a short-pulse ignition demonstration to create

a self-sustaining fusion reaction. The second is

a long-burn demonstration to maintain a self-sustaining fusion reaction long enough to study effects such as the evolution of the plasma under

steady-state burn and the buildup of reaction

products. These two tasks could be done in separate facilities or in the same facility.

For fiscal year 1988, DOE has requested funds

to start building a Compact Ignition Tokamak

(CIT) to study short-pulse ignition issues (figure

4-15). This device, to be located immediately adjacent to TFTR at Princeton Plasma Physics Laboratory, is anticipated to cost about $360 million

(including diagnostic equipment and associated

R&D) and will take advantage of existing equipment at the site. Operation is scheduled to be31 Argonne National Laboratory, Technical P/arming Act;v;~y: Fina/ Report, op. cit., p. 79.
96 . Starpower: The U.S. and the International Quest for Fusion Energy

SHIELD 

Figure Preliminary Design

SOURCE: Princeton Plasma Physics Laboratory, 1987.

gin in 1993, and annual operating cost is estimated at about $75 million. According to a review

by a panel of the Magnetic Fusion Advisory Committee (M FAC)32, CIT will be able to study most

of the effects that generation of alpha particles

might have in a fusion plasma.

Ever since TFTR was designed in the mid- 1970s,

the design for a successor device has been a topic

of active interest in the fusion community. As far

 Committee is a committee 

 of scientists and engineers from academia, national laboratories, and industry that advises DOE on technical matters 

 fusion research. An (Panel XIV, chaired by Dale

Meade of Princeton Plasma Physics Laboratory) reviewed plans for

 in the Report on Assessment Phenomena

 Feb. 10, 1986. The report was reviewed by the full in Advisory

Committee on Compact Experiments (Charge XIV),

submitted to Dr. Alvin Director, Off Ice of Energy Research, Department Energy, Washington, DC, February 1986.

back as 1977, proposals were made for compact,

high-magnetic-field tokamak devices using highperformance copper magnets; this is the approach

that was selected for CIT. Other proposals, which

were ultimately not adopted, called for long-pulse

tokamaks using superconducting magnets and

costing well over over $1 billion. The CIT design

is intended to focus on scientific aspects of the

fusion process, and it will not necessarily form

the engineering basis for future fusion reactors:

ClT’s copper magnets consume amounts of electricity that would be prohibitive for commercial

purposes, they cannot operate for longer than a

few seconds at a time without overheating, and

their compact size does not provide enough

room for a blanket to recover fusion energy or

breed tritium. But CIT will have the ability to resolve critical physics uncertainties sooner and at

lower cost than an experiment having more of
Ch. 4.—Fusion Science and Technology ● 9 7

the engineering features that a reactor wouId require. Moreover, although specifics of the CIT design may not be applicable to future reactors, the

overall approach of high-field, high-performance

magnets in fact may be relevant if such magnets

can be made with superconducting technology.

CIT is being designed through a national effort

with wide-based technical support, and the project has been endorsed by MFAC as a “cost-effective means for resolving the technical issues

of ignited tokamak plasmas.”33 MFAC determined

that the “existing tokamak data base is adequate,

with credible extrapolation, to proceed with the

design of the ClT,” and that by fiscal year 1988

“we shouId have acquired sufficient information

from present large machines to support proceeding with the construction of the CIT.”34 MFA C

also stated that CIT “should be part of a balanced

overall fusion program, “ implying that it should

not drain funds away from “other essential elements . . . in the DOE Magnetic Fusion Program

Plan. ”

35

Long-term burn issues, which cannot be addressed by CIT, will require another device in the

future. Even if constructed solely to study physics

issues, such a device would probably cost at least

$1 billion. If other functions such as nuclear technology testing were incorporated, the cost would

be even higher.

Fusion Materials

According to TPA, “the ultimate economics

and acceptability of fusion energy, as with most

other energy sources, will depend to a large extent on the limitations of materials for the various components.”36 Addressing the specific material issues identified earlier in the chapter

requires faciIities for testing and evaluating candidate materials. Some of this testing can be done

by exposing materials to neutrons in fission reactors. Fission-generated neutrons, however, dif33Magnefic Fusion Advisory Committee Report on compact ignition Experiments (Charge X/V), letter from MFAC chair Fred L.

Rlbe to Dr. Alvin Trlvelpiece, Director, Office of Energy Research,

Department of Energy, Feb. 24, 1986.

]~1 bid,

3jlbid.

16 Argonne N~tlona [ Laboratory, Techrr/ca/ ~/.3flfl;~gAct/~;ty: FIrra/ Report, op. cit., p, 259,

fer in energy and effects from fusion-generated

neutrons; tests of materials in fission reactors have

to be carefully arranged in order to provide

meaningful data on fusion neutron effects.

Eventually, a high-intensity source of 14-millionelectron-volt (14-MeV) neutrons will be required

to evaluate the lifetime potential of most materials. To accelerate the effects of aging, the test facility must generate neutron irradiation levels significantly higher than those expected in a reactor.

Such levels could be provided by a device such

as a driven fusion reactor, which would generate fusion neutrons but consume more power

than it generated. Such a device would be completely impractical as an energy source, but could

bean effective method of generating high fusion

neutron intensity over a small volume (1 O to

1,000 cubic centimeters).

TPA estimates that a materials irradiation test

facility would cost from $150 million to $250 million and would take about 4 years to build. Materials testing would also require several additional facilities each costing $10 million or less.

Fusion Nuclear Technology

Fusion nuclear technologies are those involved

with the recovery of energy from the fusion reaction and the breeding and recovery of tritium

needed to replace the tritium consumed in the

reaction. Most of the nuclear technology functions of a fusion reactor are incorporated in the

first wall, blanket, and shield.

The first wall/blanket test program is currently

at a very early stage. However, the characteristics of the required experiments have been defined in the FINESSE study .37 A number of experiments, each costing about $5 million, will be

important for guiding the future of the program.

Several larger experiments will be needed to follow upon the earlier ones; each of these will cost

up to tens of millions of dollars to build and $1

million or more a year to operate .38

j~he FINESSE study IS a 3-year study done to r DOE Ink o I \ I ng

organizations and scientists from the U n ited States, ELI rope a nci

Japan. The study produced many pub]lcatlons; one example IS ‘A

Study of the Issues and Experiments (or Fusion Nuclear Technology,” by M. A. Abdou, et al., Fwon Technology 8, November 1985.

IBArgonne Nationa I Laboratory, Technic a/ f’/.? nngng Ac~l~’lty. FI -

na/ Reporf, op. cit., table 4.13, pp. 234-236.
98 ● Starpower: The U.S. and the International Quest for Fusion Energy

After individual facilities enable blanket concepts and components to be designed and the

number of options to be reduced, a large-scale

nuclear technology demonstration facility will be

required to integrate these components and test

them under fusion reactor conditions. Such a

large-scale device must not only produce enough

fusion power to provide a realistic environment

for nuclear technology testing, but it must also

incorporate development and construction of the

individual nuclear technology systems themselves.

If this device is also intended to address the

physics issues associated with long-term fusion

burns, it will become still more complex and expensive.

One possibility, identified by the FINESSE study

and reviewed and adopted by TPA, is building

a nuclear technology demonstration facility that

does not simultaneously serve as the long-burn

physics test facility. A device built solely to study

nuclear technologies would need a source of

fusion-generated 14-MeV neutrons, but this source

would not need to be an ignited plasma. Such

a device could test scaled-down versions of nuclear technology components, provided that

these results could be applied with confidence

to reactor-sized versions. TPA estimated that such

a nuclear-technology-only device would cost

about $1 billion and would take 5 to 6 years to

build. TPA did not estimate operating costs for

this device.

TPA identified as a second possibility an engineering test reactor (ETR) that would include both

long-term burn physics and nuclear technology

studies. Such a device would require an ignited

or near-ignited plasma, making it big enough to

accommodate full-size nuclear technology components. Both the more stringent physics requirements and the need for full-scale nuclear technology components would make an ETR much

more expensive than a nuclear-technology-onIy

facility. TPA estimated the cost to build an ETR

at about $3 billion. It did not estimate operating

costs but said that the experience with TFTR

would suggest $150 million annually.39

WIt is not clear how this estimate of $150 million is obtained; it

is not computed merely by assuming the annual operating expense

of a device to be a specific fraction of its capital cost. Were the

estimate made in this manner, it would be considerably higher.

If a nuclear-technology-only device is built instead of an ETR, an additional device would be

required specifically to study long-term burn. This

additional experiment would probably cost more

than $1 billion. Further expense would come later

when the tested nuclear technology systems were

scaled to reactor-level and integrated with a

reactor-sized plasma. Thus, the cost of an ETR

cannot be compared only to the cost of a nuclear

technology device plus a long-term burn device.

Although DOE recognizes the need for an ETR

or equivalent, it has no plans to build one. The

Japanese and European programs each have

plans to design such a device independently, but

neither has yet committed to its construction. The

Soviet and the U.S. fusion programs, on the other

hand, appear to prefer international collaboration on such a facility. The U.S. Government has

proposed to the other major fusion programs that

conceptual design of an international engineering test reactor, called the International Thermonuclear Experimental Reactor (ITER), be jointly

undertaken. The U.S. proposal does not extend

to multinational construction of such a device.

However, at the conclusion of the conceptual design effort, the parties could decide whether they

wanted to proceed with construction, either independently or jointly. Possible avenues of future international collaboration in fusion research

are discussed in chapter 7.

Resource Requirements

Schedule

TPA identified six major decision points that determine the course and schedule of future fusion

research, leading up to the overall assessment of

fusion’s potential. In figure 4-16, each decision

is pegged to a key technical issue and to a year.

The ratio of annual operating expense to capital expense for TFTR

is about 15 percent, and that projected for CIT is about the same

if the value of existing facilities at Princeton Plasma Physics Laboratory is included in ClT’s capital cost. Applying this 15 percent

ratio to an engineering test reactor would predict annual operating expenses of close to $500 million.

However, fusion scientists argue that there is no reason to believe the ratio of operating expense to capital expense to be the

same for an ETR as it is for significantly smaller devices. They agree

that the more a device costs to build, the more it will cost to operate. However, they maintain that there is no reason to expect capital and operating costs to increase at the same rate,
Ch. 4.—Fusion Science and Technology “ 99

Figure 4-16.-Top Level Decision Points in the Magnetic Fusion Program

SOURCE: Argonne National Laboratory, Technical Planning Activity: Final Report, commissioned by the U.S. Department of Energy, Office of Fusion Energy, ANL/FPP-87-1,

January 1987, figure S.8, p. 23.

TPA did not examine all the possible scenarios

resulting from different timings and outcomes for

these decisions but instead adopted a “reference

scenario” believed to reflect current DOE planning. The years in figure 4-16 are taken from the

reference scenario, which is shown in greater detail in figure 4-17.

In the reference scenario, the decision to proceed with CIT as the short-term burn experiment

is made in 1987. By about 1990, the decision is

made to combine nuclear technology studies and

long-term burn physics issues in a single engineering test reactor, possibly ITER. At about the same

time, decisions are made concerning the nature

of a materials testing facility and the selection of

confinement concepts to be tested at the proofof-principle scale. By 1997, certain alternate confinement concepts successfully showing proofof-principle are selected for reactor-scale demonstration, and the overall assessment of fusion

is targeted for 2005. TPA does not conclude that

the reference scenario is fastest, cheapest, or most

assured of success. Rather, it shows that an exhaustive process of technical review has not uncovered any inconsistencies.

cost

TPA estimates that the worldwide research required between 1987 and 2005 under the reference scenario will cost in the range of $20 billion. This cost does not include an integrated

fusion facility, demonstration reactor, or any

other facility constructed after the assessment of

fusion in 2005. Total operating cost worldwide

is judged to be relatively constant at about $800

million annually, and total yearly funding for fusion research increases to about $1.5 billion in

the mid-1990s when construction cost is added.

The total construction budget is estimated at

about $6 billion, half of which is required for an

engineering test reactor.

TPA acknowledges that the ground rules used

for cost projection could have been applied more
January 1987, figure S.1O, p. 27.

uniformly, that no iterative review of the cost estimates was undertaken, and that no effort was

made to estimate the resources required for alternate research scenarios. Nevertheless, the report

states that the information gathered is sufficient

to present “a broad view of the resources required for a full assessment of the commercial

potential of fusion.”40

Some critics of TPA’s cost estimates argue that,

since TPA was not charged with designing, managing, and executing an actual research strategy—

indeed, TPA was forbidden from performing such

programmatic planning, which is strictly DOE’s

domain–the total cost represents a sum of “wish

lists” rather than a realistic budget. According to

these critics, without the requirement to conduct

the politically difficult task of eliminating research

that, although useful, may not be necessary, the

 Laboratory, 

 Report, op. cit., p. 28.

estimated total cost is higher than an actual manager would spend when faced with fiscal constraints. Similarly, these critics complain that any

study done by experts from a single field has an

inherent bias towards overestimating that field’s

research requirements. Researchers in a field are

presumed to have an interest in maintaining or

increasing their field’s funding, these critics argue, and the researchers would not have any incentive to prepare a study underestimating the

cost of research if such a study might be used as

justification for cutting the field’s research budget.

Other critics, however, feel that any bias in

TPA’s estimated total is likely to be in the direction of underestimating the total rather than inflating it. Since each technical aspect of the study

was analyzed by experts in the field, some degree of technical optimism is probably inherent

at each stage; unanticipated difficulties would

drive the cost of the research program above

TPA’s estimates. Moreover, these critics suggest,
Ch. 4.—Fusion Science and Technology ● 101

it would not be in the collective interest of the

fusion community to estimate a higher total cost

than necessary, since continued support of the

fusion program depends on perceptions that its

benefits are worth its cost. Overestimating the total cost could threaten the program’s support.

The process by which TPA estimated the total cost of future fusion research involved a wide

degree of fusion community participation, and

OTA can find no evidence that the estimate is

flawed. However, OTA also recognizes that while

the researchers in any technical field are the

most qualified to estimate costs of experiments

in that field, they are also the beneficiaries of

support given to the field. Therefore, their estimates may be influenced by non-technical factors, although it is not clear whether the estimate would be too high or too low as a result.

Summary

Probability of Success

It seems likely that at the conclusion of the research program, fusion’s technological feasibility—the ability to use fusion power to generate

electricity—can be shown. The fusion program

has made steady progress over the last 35 years

on the key technical issues. It is still possible that

fusion’s scientific feasibility will be impossible to

demonstrate, due to surprises in the behavior of

a plasma that generates substantial amounts of

fusion power. However, successfully attaining ignition in CIT will resolve most of the scientific uncertainties.

Most of the subsequent scientific and engineering challenges in designing and building a reactor

have been identified. Once scientific feasibility

is established, a concerted and well-funded research effort should be able to develop a reactor

that produces fusion power. However, it cannot yet be determined whether or not such a

fusion reactor will be commercially attractive.

Characteristics and prospects of fusion as a commercial energy source are discussed in chapter 5.

Findings

Estimates of the annual worldwide funding required to evaluate fusion’s potential early in the

next century are several times today’s annual U.S.

fusion research budget. The estimated annual

worldwide funding is, however, on the order of

the amount now spent each year by all the world’s

major fusion programs put together. The funding estimates suggest three possibilities to U.S.

policy makers for continuing the U.S. fusion research program:

1. With funding levels several times their present level and with a significant measure of

technical success, the U.S. fusion program

can decide on its own whether or not to begin the demonstration and commercialization of fusion power in the early part of the

next century.

2. If the major world fusion programs can collaborate and plan their research efforts to

complement each other and eliminate duplication, and if the effort has a significant

measure of technical success, a collective

assessment to proceed with fusion’s development could be made early in the 21st century. In this case, only modest increases in

funding would be required for each of the

world’s fusion programs, with the exact

amount of the increases depending on how

well the programs were able to avoid duplication of research.

3. If major international collaboration is not attained, and if the U.S. fusion budget is not

increased to the point where the necessary

research can be carried out domestically, the

United States cannot assess fusion’s potential until later in the next century.

These possibilities form the basis of the policy

options discussed in greater detail in chapter 8,
Chapter 5

Fusion as an Energy Program 
CONTENTS

Page

Characteristics of Fusion Electric Generating Stations. . . . . . . . . . . . . . . . . . . . . . . 105

Risk and Severity of Accident . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..106

Occupational Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............108

Environmental Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .............109

Nuclear Proliferation Potential . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ......112

Resource Supplies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................113

cost. . . . . . . . . . . . ● * * *, . . * ***..*... 6.**.....*...*.*. . ..............113

The Supply of and Demand for Fusion Power . . . . . . . . . . . .................116

The Availability of Fusion Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .......116

The Desirabitity of Fusion Power.... . . . . . . . . . . . . . . . . . . . . . . . . . .

Comparisons of Long-Term Electricity Generating Technologies. . . . .

Fusion’s Energy Context . . . . . . . . . . . . . . . . . . .:....

Conclusions . . . . .. .. .. .. .. .. .. .. .. ... ... ... ..$..

Characteristics of Fusion Reactors . . . . . . . . . . . . . . . .

Timetable for Fusion Power . . . . . . . . . . . . . . . . . . . . .

Figure No.

5-1. Post-Shutdown Radioactivity Levels . . . . . . . . . . . . .

5-2. Post-Shutdown Afterheat Level s . . . . . . . . . . . . . . .

5-3. Projections of Global Primary Energy Consumption

—

. . . . . . . . . . . . .

. . . . . . . . . . . . .

. . . . . . . . . . . . .

. . . . . . . . . . . . .

.**..... . . . . .

. . . . . . . . . . . . .

to 2050. . . . . .

Table No.

5-1. Principal Locations of Potential Hazardous Agents

in D-T Fusion Reactors . . . . . . . . . . . . . . . . . . . . . . .

5-2. Utility Requirements Summary . . . . . . . . . . . . . . . . .

5-3. Comparison of Prospective Long-Range Electricity Supply Options

. . . . . . . . . . . . .

. . . . . . ● ✎ ✎ ✎ ✎ ✎ ✎

. . . . . . . 117

. . . . . . . 119

....*O . 123

. . . . . . . 127

. . . . . . . 127

. . . . . . . 127

Page

. . . . . . . 110

● . . . . . . 111

. . . . . . . 126

Page

. . . . . . . 109

. . . . . . . 118

. . . . . . . 124
Chapter 5

Fusion as an Energy Program

The primary long-term goal of U.S. fusion research is to develop a fusion reactor that is an

attractive source of electricity. ’ The overall role

that fusion might play in the future energy supply of the United States depends on the charac-

] Fusion a I so may be \a I uable I n a n u m her cd non-electric appl Icatlons, descrl bed i n ap~). A.

teristics of such a fusion reactor and on the characteristics of other energy technologies with

which fusion will compete. It is too early to evaluate either of these characteristics: fusion’s commercial prospects are not yet known and neither

are the prospects of developments i n other technologies. However, preliminary analyses can be

performed on the basis of fusion system studies

conducted to date.

CHARACTERISTICS OF FUSION ELECTRIC GENERATING STATIONS

Pre-conceptual designs and feasibility studies

for fusion generating stations were developed as

long ago as 1954.2 However, it was not until the

early 1970s that studies began to simultaneously

address the plasma physics, structural materials,

operating characteristics, economics, and environmental implications of fusion reactors.3 During the late 1970s and early 1980s, comprehensive system studies and comparative models were

developed to evaluate the interdependence of fusion reactor performance and various scientific

and technological parameters.

These studies represent a mix of technological

optimism and conservatism. They optimistically

assume that the research and development (R&D)

effort mapped out in chapter 4 of this assessment

will be successfully completed and that it will

permit a fusion reactor to be designed and built.

At the same time, studies are inherently conservative in that they cannot account for as-yetunforeseen developments and innovations i n fusion and competing technologies.

The studies have been especially valuable in

identifying improvements in fusion physics or

technology that appear to have the greatest po2L. Spitzer, Jr., et al., Problems of the Stellarator as a Usefu/ Power

Source, NYO 6047 (Princeton, NJ: Princeton University, 1954),

‘The evol ut Ion of fusion reactor stud Ies 15 d i scussed I n FujIorJ Reactor Desgn: On the RoJd to Comrnercl.]/iz~ tlon, by G. L Ku ICI nskl, Fusion Engineering Program, NUC Iear En~lneerlng Department,

Unwerslty of Wlsconsln, LJWFDM-5.29, Nlachson, \Vl, May 31, 1983,

p. 3.

tential for making fusion reactors attractive and

competitive. Their value to the fusion program

notwithstanding, system studies should not be

considered definitive assessments of future fusion

reactors. Given that the scientific and technological base for fusion has not yet been established,

fusion system studies are inherently based on incomplete information, and the values calculated

for reactor parameters such as capital cost and

cost-of-electricity must be considered highIy uncertain. As a result of the technical progress made

in fusion research, system studies today describe

reactors that are very different from those envisioned 30 years ago. It is likely that the fusion reactor that eventually enters the marketplace will

make today’s designs appear just as dated.

The discussion that follows identifies generic

features of future fusion reactors as well as factors that depend on particular design choices. The

focus is on reactors that produce electricity from

fusion alone, called pure fusion reactors, as distinguished from fusion reactors that draw part of

their energy from fission or that are used to make

fissionable fuel.4 Much of the discussion draws

on comparisons of fusion technology to presentgeneration light-water reactor fission technology,

the closest analog to fusion for which significant

operational data exists. Fusion and fission plants

105
106 ● Starpower: The U.S. and the International Quest for Fusion Energy

are comparable because both are nuclear technologies suited for central-station power generation, and because they share some of the same

environmental and safety concerns. However,

the further that a technology is extrapolated beyond present experience, the less certain any of

its features become. As a resuIt, all characterizations of future systems—including the ones in this

chapter—should be treated with extreme caution.

Risk and Severity of Accident

The D-T fusion process has several advantages

over fission that should make it easier to assure

the safety of a fusion reactor than of a fission reactor. This statement does not imply that existing fission reactors are unsafe, or that fission technology will not continue to develop and improve.

However, assuring public safety with fusion technology should be easier for the following reasons:

● Fusion reactors cannot sustain runaway reactions. Fuel will be continuously injected,

and the amount contained inside the reactor

vessel at any given time would only operate the reactor for a short period (probably

seconds or less). A fission reactor, on the

other hand, contains several years of fuel in

its core—a far greater amount of stored energy

potentially available for release. Moreover,

the conditions necessary to sustain a fusion

reaction are difficult to maintain; any significant system malfunction would stop the reaction.

● Fusion reactors should require simpler postshutdown or emergency cooling systems

than fission reactors, if such systems are

needed at all. Due to the decay of radioactive materials in the reactor, both fusion

and fission reactors will continue to generate heat at a small fraction of the full power

rate after they have been shut down. I n a

fission reactor, this decay heat, or afterheat,

is largely due to fission byproducts that accumulate in the spent fuel rods. In a fusion

reactor, afterheat results mostly from radioactivity induced in the reactor structural materials, and the afterheat level is highly dependent on the choice of those materials.

With appropriate materials choices, afterheat

from fusion reactors should be much less

than from fission reactors.

potential accidents that could occur in fusion reactors should be less serious than

those that could take place in fission reactors.

With suitable materials choices, the radioactive inventory of a fusion reactor should

be considerably less hazardous than that of

a fission reactor. Fusion reactors would not

contain biologically active fission products

such as strontium and iodine. Moreover, the

radioactive materials in a fusion reactor

would generally be less likely to be released

in an accident than wouId those in a fission

reactor, since they would largely be bound

as metallic structural elements. The only

volatile or biologically active radioactive

component in a fusion reactor would be the

active tritium inventory; gaseous and volatile radioactive products in a fission reactor

would be present in amounts orders of magnitude greater.

recent study of fusion’s environmental, safety,

and economic attributes quantitatively compares

the safety of fusion and fission designs. s This

study, referred to here as the ESECOM report,

sorts various fission and fusion reactor designs

into four categories according to the means by

which prompt off-site fatalities are prevented in

the event of an accident. Some of the designs

studied depend on active safety systems to prevent off-site fatalities. These reactors can be safe,

but demonstrating their safety involves certifying

that the safety systems will work as expected during all conceivable accidents. In other designs,

Jjohn Holdren, et al., Exp/oring the Cornpetiti~7e Pofentia/ ofMa~-

netic Fusion Energy: The Interaction ot’fconomics With Safety and

Environmental Characteristics, excerpts from the Report of the Senior Committee on Economic, Safety, and Environmental Aspects

of Magnetic Fusion Energy (ESECOM). Interim results from this study

were presented to the Magnetic Fusion Advisory Committee in

Princeton, NJ, on May 19, 1987; the full report should be published

as a Lawrence Livermore National Laboratory report in September 1987. This study will be cited hereinafter as the ESECOM report.

ESECOM analyzed and compared the environmental, safety, and

economic aspects of eight pure fusion reactor designs, two fission/fusion hybrids, and four types of fission reactor. Of the pure fusion

reactors, six were tokamaks and two were reversed-tield pinches;

both the hybrid reactors were tokamak-based.
Ch. 5.—Fusion as an Energy Program ● 107

and the safety of these systems is much easier to

demonstrate. 6

The levels of safety assurance derived by

ESECOM, ordered by increasing ease of demonstrability, are:

● Level 4: Active Protection. This level of protection depends on the proper operation of

active safety systems to ensure safety.7 It is

extremely difficult to certify that such systems

will indeed work as expected in case of accident. These systems must be designed to

respond to particular contingencies, and

deciding which accident scenarios should be

covered is not easy. Furthermore, as the

1986 Chernobyl accident in the Soviet Union

showed, active safety systems can be disconnected. At this level of protection, it is impossible to eliminate the risk of operator

error.

● Level 3: Small-Scale Passive Protection. At

this level, safety does not depend on active

safety systems. Moreover, failure of compobThe analysis in this study computes ‘‘worst-case” radiation exposures to members of the public by calculating the maximum radiation dose deliverable to an individual at the worst possible location at the plant boundary, under weather conditions that keep

the radiation from dispersing. Effects that would serve to mitigate

the delivered dose, such as buildings, rain, or fallout, were not included (except that the effect of buildings on the wind pattern was

included). Absence of prompt fatalities corresponds to limiting the

‘‘worst-case” dose to under 200 reins, an amount of radiation exposure generally accepted to be the minimum capable of causing

a prompt fatality in the absence of medical treatment. This radiation dose is about 2,000 times the total dosage typically received

in one year due to cosmic rays and other naturally occurring sources

of radiation.

In addition to prompt radiation dose, the study also considered

the long-term dose from ground contamination due to an accident.

However, these long-term dosages were not used to define the categories of safety assurance. Long-term effects of radiation release

are more difficult to determine than prompt effects because the

effects of long-term, low-level exposure to radiation are highly controversial. Estimates of the cancer fatalities resulting from a given

long-term, low-level exposure vary by more than a factor of 10.

7U rider the ESECOM analysis, any system such as an emergency

cooling system that would have to be activated or powered at the

time of an accident, or any system that would have to be actively

turned off, is considered an active system. A containment building is considered an active system under this definition since penetrations such as airlocks, ventilation systems, and plumbing are managed by active systems. Therefore, designs relying significantly on

containment buildings to prevent escape of radiation could not

achieve a rating higher than Level 4.

nents such as relief valves and pump seals—

in conjunction with the failure of any active

systems—could be tolerated without risking

off-site fatalities. However, ensuring safety

at this level requires assuming the integrity

of key systems such as coolant loops, as well

as maintaining the large-scale physical integrity of the overall structure. It would have

to be proven that passive design features

alone could keep these critical components

or systems from being damaged under credible accident scenarios.

Level 2: Large-Scale Passive Protection. A

large-scale passively protected reactor would

be able to prevent the release of dangerous

amounts of hazardous materials as long as

certain large-scale structures remained intact.

Such a system would not rely on active safety

systems and would be able to withstand any

combination of small-scale component or

system failures. Demonstrating the safety of

such a reactor wouId only require showing

that no credible accident could destroy the

large-scale geometry of the device.

Level 1: Inherent Safety. A reactor with this

degree of safety assurance could be shown

to be incapable of causing an immediate, offsite fatality in the event of any conceivable

failure, including total system reconfiguration

(e.g., it would remain safe even if the entire

reactor were somehow crumpled up into a

ball). This level of protection is assured by

the properties of the reactor materials in one

of two ways: either the radioactive inventory

must be so small that, if totally released, it

could not constitute a lethal dose to the public, or the inventory must consist of materials that could not be melted, converted into

volatile oxides, or otherwise dispersed by the

sudden release (in an explosion, fire, or

power surge) of all the plant’s stored energy.

According to the ESECOM report, attributes

of the fusion process show that fusion reactors

should be able to achieve greater degrees of

safety assurance than fission reactors. Of the

eight fusion designs that ESECOM evaluated, one

was a Level 1 system, three were Level 2, one
108 ● Starpower: The U.S. and the International Quest for Fusion Energy

was Level 3, and three were Level 4. Design

changes were identified for several of the Level

3 or 4 fusion systems that could raise them to

Levels 2 or 3, respectively. ESECOM found that

present-generation commercial light-water fission

reactors are Level 4 systems, and that two “inherently safe” fission reactor designs now under

investigation should be capable of reaching Level

3 on this scale.

Different fusion designs varied significantly in

terms of the maximum radiation dose that could

be delivered to the public in an accident. Designs

using low-activation materials, which do not generate long-lived radioactive byproducts under

neutron irradiation, and designs operating on advanced fuel cycles were calculated to have a

higher degree of safety assurance than the “reference” design, an updated version of a tokamak

reactor study originally published in 1980.8 However, materials selections and design choices are

also possible that yield fusion reactors that require

active safety systems.

ESECOM concluded that Level 2 fusion reactors

should be possible to design, and that Level 1

designs–although more difficult due to limited

materials choices—should also be possible. None

of the fission designs ESECOM analyzed could attain these levels of safety assurance. Although fission designs are being developed that appear to

have greater degrees of safety assurance than existing fission reactors, fusion appears to have

some fundamental advantages. Many of the potentially dangerous substances present in fission

reactors are either fuels or fission byproducts that

are inherent to the fission reaction. The products

of the fusion reaction, on the other hand, are not

in themselves hazardous. Tritium fuel does pose

a potential hazard, but according to the ESECOM

BCharles C. Baker, et al., STARFIRE—A Commercial Tokamak

Power P/an( Study, AN L/FPP-80-l, Argonne National Laboratory,

1980. The STARFIRE study, conducted by a team of 70 researchers, is one of the most comprehensive fusion reactor design studies

completed to date. It presents a conceptual design of a full fusion

powerplant, including descriptions of the tokamak reactor as well

as all the associated subsystems in the remainder of the facility.

The STARFIRE study has been extensively drawn upon by, and

provides a base of comparison for, many subsequent analyses ot

fusion reactors and system designs. The ESECOM report chose the

STARFIRE design, updated with lower activation materials and a

more recent blanket design, as its ‘‘point-of-departure’ reference

case.

report even the complete release of the active

tritium inventory of current reactor designs under adverse meteorological conditions would not

produce any prompt fatalities off-site.9 There is

much greater freedom to choose appropriate materials that minimize safety hazards in fusion reactors than in fission reactors. Therefore, a higher

degree of safety assurance should be attainable

with fusion.

Occupational Safety

Most of the occupational hazards a worker

might encounter at a fusion reactor site are already familiar from other occupations. Table 5-1

shows the locations of potential hazards during

the operation and maintenance of a D-T fusion

reactor.

Of the potential hazards listed, the least is

known about the effects of magnetic fields. There

is no reason to suppose that the steady or slowly

varying magnetic fields associated with fusion reactors could cause adverse health effects. However, little is known definitively about the biological effects of such fields; after many years of

research, the technical literature is “extensive and

often contradictory. ” 10 The U.S. Department of

Energy (DOE) established interim occupational

magnetic field exposure guidelines on an ad hoc

basis in 1979, although the committee that developed these guidelines expressed “strong concerns about the lack of data upon which one can

construct appropriate exposure criteria,”11

9joh n Hold ren, et al., ESECOM Report, op cit. Larger “inactive”

tritium supplies would be stored in the plant in addition to the active working inventory, but these could be divided up and extremely

well protected.

10J, B, cannon (ed .), Background Information and Technical Basis for Assessment of Environmental Implications of Magnetic Fusion Energy, DOE/ER-01 70, prepared by the Oak Ridge National

Laboratory for the U.S. Department of Energy, Office of Fusion

Energy, Division of Development and Technology, August 1983,

p. 6-2.

This document, hereinafter referred to as Background /formation, served as the principal reference for a generic Environmental

Impact Statement that was prepared for the magnetic fusion program. The generic statement, although completed, has not been

reviewed and approved by DOE. DOE has chosen not to file a

generic impact statement for the program as a whole but rather

to prepare specific statements for individual fusion facilities as

needed.

I I Letter from Dr. Edward Alpen, Director of the Dormer Laboratory, Unwerslty of California at Berkeley, and Chairman of the committee established to set interim magnetic field exposure standards,

to Dr. Kenneth Baker, U.S. Department of Energy, July 23, 1979.
Ch. 5.—Fusion as an Energy Program w 109

Table 5-1 .—Principal Locations of Potential Hazardous Agents in D-T Fusion Reactors

Locations of possible exposure Locations of possible exposure

Hazard during operation during maintenance

Radiation from tritium. . . . . . . . . . . . . . . ●

●

Radiation from activation products. . . . ●

Radiation from neutrons . . . . . . . . . . . . . ●

Non-radioactive toxic materials . . . . . . . ●

Radiofrequency (RF) fields . . . . . . . . . . . ●

●

Magnetic fields. . . . . . . . . . . . . . . . . . . . . .

Tritium recovery systems ●

Coolant loops ●

●

Coolant loops ●

●

●

Not present in accessible areas ●

Possibly in auxiliary reactor systems ●

Near power sources ●

Along waveguides

Environment of reactor hall ●

Reactor hall and structure

Blanket processing

Fuel recycling

Reactor hall and structure

Blanket processing

Steam generator

Not present

Chemical processing

Not present unless RF components

are being tested

Not present unless magnets are

being tested

aHazards are only listed for areas where personnel will be permitted, personnel will not be permitted in the reactor hall during reactor operation, so activation products

and neutron radiation present there are not considered occupational hazards in this table.

SOURCE Adapted from J B. Cannon (ed), Backrground Information and Technical Basis for Assessment of Environmental Implications of Magnetic fusion Energy,

DOE/ER-0170, prepared by Oak Ridge National Laboratory for the U.S. Department of Energy, Office of Fusion Energy, Division of Development and Technology, August 1983, table 6.1, P 6-2

These standards are still being used on a trial

basis; although researchers analyzing this issue

have flagged uncertainties that call for further research, they have still not found many well-documented studies that show detrimental biological

effects of static (non-varying) or slowly varying

magnetic fields such as those to be found in fusion reactors. The National Committee on Radiation Protection and Measurement has established a subcommittee on Biological Effects of

Magnetic Fields to recommend limits on magnetic

field exposure; this subcommittee is in its final

stages of document preparation prior to submission to the full committee. ’ 2

Significant exposure to magnetic fields in or

near a fusion reactor probably would be limited

to plant workers because magnetic fields extending beyond the site boundary are not expected

to be stronger than the earth’s field. The interim

standards established by DOE were for occupational exposure only, and the committee that developed them stated that it was “not prepared

to offer an exposure criteria for general population exposure." 13

Environmental Effects

Radioactive Waste

The main environmental problem with fusion

reactors is expected to be radioactive waste. Although the reaction products of the D-T fusion

reaction are not radioactive, the fusion reactor

itself—particularly the first wall, blanket, shield,

and coils—will be. The first wall will be the most

severely affected; the cumulative effects of radiation damage will require that the first wall be

replaced every 5 to 10 years and disposed of as

radioactive waste.

The type and amount of radioactive waste generated by a fusion reactor is highly dependent

on the choice of materials. With appropriate materials, fusion reactors can avoid producing the

long-lived, intense, and biologically active wastes

inherently produced by fission reactors. According to the ESECOM report, although fusion wastes

may have greater volume than fission wastes, they

will be of shorter half-life and intensity and should

be orders of magnitude less hazardous. ” The

wastes from fusion reactors operating with adI ZI nformation provided to OTA staff by Dr. Donald ROSS, Acting

Director, Occupational Safety and Health Division, Office of Operational Safety, U ,S. Department of Energy, Apr. 22, 1987; and by

Dr. Dennis Mahlum, chairman ot’ the National Committee on Radlatlon ProtectIon and Measurement Scientific Committee 67 on

Biological Effects of Magnetic Fields, Apr. 28, 1987.

13 Letter from A I pen to Baker, note 1 1 above.

14ESECOM measured racjioactive waste hazard by calcu Iating the

dosages that future “intruders” could acquire by excavating or farming a radioactive waste site hundreds of years from now. Radioactive waste produced by the fusion designs ESECOM studied were

orders of magnitude less hazardous than those produced by tlssion designs by this measure.
110 . Starpower: The U.S. and the International Quest for Fusion Energy

vanced, non-tritium-based fuel cycles would be

even less radioactive than those from D-T fusion

reactors.

ESECOM’s estimates of radioactive waste hazards also indicate that fusion designs differ

among themselves by several orders of magnitude. The study found that advanced “lowactivation” fusion designs could be tens to hundreds of times better than the fusion reference

design, and that other designs could be hundreds

or thousands of times worse if the wrong materials are chosen. ESECOM concluded that with

proper materials selection, radioactive waste from

all of the fusion designs could qualify as low-level

waste under existing Nuclear Regulatory Commission regulations. 15

Figure 5-1 shows the dependence of fusion reactor radioactivity levels on materials selection.

Figure 5-2 shows the corresponding dependence

for afterheat produced by radioactive decay. For

the top curve in each figure, the reactor first wall

and blanket are assumed to be made out of a type

of steel. The lower curve, having radioactivity and

afterheat levels thousands to millions of times

lower, assumes that low-activation materials are

used in the blanket and first wall.16

These figures represent the potential of lowactivation materials to reduce radioactive wastes

but do not necessarily address the feasibility of

using these materials. The source for figures 5- I

and 5-2 was a preliminary conceptual design

study that attempted to design credible replacements using low-activation ceramic materials for

all reactor structures in the high neutron flux zone

of the STARFIRE reactor (footnote 8, above). Engineering feasibility of these materials was considered, and at an initial level of analysis the designs

were found to be achievable. However, using

 al., 

 induced radioactivity intrinsic to the low-activation materials themselves is extremely small; the majority of the radioactivity shown by the “low-activation” curve more than one day after

shutdown is due to iron impurities. According to Cannon, Background op. cit., p. 3-41, realizing impurity levels as

low as those assumed in this figure is a “difficult and expensive

task at the present time, and may or may not be achievable at the

time rity structural materials are required

in a fusion reactor economy. ”

Figure 5-1 .—Post-Shutdown Radioactivity Levels

for Fission Breeder Reactor, Reference STARFIRE

Fusion Reactor, and Low-Activation Fusion

Reactor Design

10’

10°

ceramics for these components poses engineering issues quite different from those encountered

with the metals typically used in engineering applications today. Substantial development of materials and fabrication techniques would be required to use ceramics in a fusion reactor.
Ch. 5.—Fusion as an Energy Program ● 111

Figure 5-2.— Post-Shutdown Afterheat Levels

for Fission Breeder Reactor, Reference STARFIRE

Fusion Reactor, and Low-Activation Fusion

Reactor Design

Routine Radioactive Emissions

The total estimated radiation dosages attributable to routine releases from fusion reactors

would be a very small fraction of the radiation

dose due to naturally occurring background radiation. 17 Two types of radioactive substances

may be emitted by fusion reactors: activation

products, which are substances made radioactive

by neutron irradiation, and tritium, which is

produced in the reactor blanket and used as fuel.

Activation products would be released either

through liquid waste processing systems or plant

ventilation systems; most of the tritium releases

would be to the atmosphere.

Activation products released by fusion reactors

should be no more hazardous than those routinely

released by fission reactors. Tritium discharges

from fusion reactors, in terms of radioactivity

levels, would be much larger than activation

product emissions. However, since tritium differs

significantly from activation products in the type

of radiation emitted and the method of absorption in the body, the total radiation dosages due

to tritium releases would not be correspondingly

large.

Very preliminary estimates of tritium emissions

from fusion reactors are on the order of 5,000

to 10,000 curies per year from a 1,000-megawatt

plant. 18 Most of these emissions would occur during major system maintenance, and they might

be removable by an atmospheric detritiation system before release to the environment. Tritium

releases of this amount are well within the range

of routine tritium releases from some existing

DOE facilities. By comparison, tritium emissions

from an equivalently sized pressurized-water fission reactor—the predominant type of commercial nuclear fission reactor—would be about

 background radiation is due primarily 

cosmic and to radioactive elements contained rocks and

soils. In the United States, the dosages due to these sources vary

by factors of 2 to 4 depending on location; the typical contributions of the two sources are comparable.

Medical X-rays and provide, on average,

a radiation dosage about equal to the natural background. A substantially smaller contribution comes from the sum of other manmade sources such as atmospheric nuclear weapons tests, occupational radiation exposure, nuclear powerplant emissions, and consumer products.

 of a substance is the amount needed to

have 3.7 X radioactive disintegrations per second. Ten thousand curies have a mass of about one gram.
—

112 ● Starpower: The U.S. and the International Quest for Fusion Energy

1,400 curies per year.19 It is estimated that the

total dose to the population within 80 kilometers

(50 miles) of a routinely operating fusion reactor

should be less than 0.01 percent of the dose from

natural background sources .20

Routine Nonradioactive Emissions

The energy generated in a fusion reactor that

is not converted into electricity would be discharged as heat, primarily into the atmosphere.

In this respect, a fusion reactor would resemble

fossil fuel and nuclear fission generating stations.

Like a fission plant, but unlike a plant that burns

fossil fuels, a fusion plant would not emit combustion products such as carbon dioxide into the

atmosphere. Since carbon dioxide emissions may

potentially affect world climate, this aspect of fusion (and fission) technology could prove to be

very advantageous. Carbon dioxide emissions are

discussed later in this chapter under “Comparisons of Long-Term Electricity Generating Technologies. ”

Nuclear Proliferation Potential

A fusion reactor’s ability to breed fissionable

materials such as uranium or plutonium could

possibly increase the risk of nuclear weapons

proliferation. A pure fusion reactor would not

contain fissionable materials usable in nuclear

weapons, and it would be impossible to produce

such materials by manipulating the reactor’s normal fuel cycle. Therefore, normal operation of

a pure fusion reactor poses negligible proliferalgFusion reactor radioactive discharge and radiation dosage estimates are from Cannon, Background /nforrnation, op. cit., chs. 4

and 8, particularly tables 4.19, 8.8, and 8.9. Pressurized water reactor emissions are from Nuclear Regulatory Commission, Ca/cuIation of Releases of Radioactive Materials in Gaseous and Liquid

Eff/uents From Pressurized Water Reactors, NUREG-0017, Rev. 1,

1985, p. 2-70.

ZODOSageS estin-rated from tritium releases assume that all the

tritium is in the form of tritium oxide, or tritiated water. Tritiated

water is water in which one or both of the hydrogen atoms are

replaced by tritium atoms, and it is absorbed by and discharged

from the human body like ordinary water. These dosages represent conservative upper bounds, and are tens of thousands of times

higher than the dosages that would result if the tritium were released in the form of tritium gas. Tritium gas is not readily absorbed

by the body.

tion risk.zl However, if the blanket of a pure fusion reactor were appropriately modified, fissionable fuel could be bred there. To ensure that

fissionable materials were not surreptitiously

produced, changes to the reactor blanket would

have to be prevented. The difficulty of detecting

such changes would depend on the design of the

reactor; it is plausible that reactor designs could

be developed that would make undesirable modifications easy (or difficult) to monitor. 22

Proliferation concerns are not unique to fusion

reactors; fission reactors also pose this risk. Depending on the fuel cycle used, the proliferation

potential of fission can be much greater than that

of a pure fusion reactor. After being irradiated

in the core of a fission reactor, uranium fuel will

be converted into plutonium, which can be extracted from the uranium and other byproducts

by chemical reprocessing, Alternatively, plutonium can be produced in breeder reactors (pure

fission or fission/fusion hybrid) designed explicitly

for plutonium production. If either reprocessing

or breeder reactors become used on a wide scale,

it is possible that material usable for nuclear

weapons could be produced and extracted during the production, processing, and transportation of fissionable fuel.23

ZI Pure fusion reactors do contain tritium, which could be used

in thermonuclear weapons such as the hydrogen bomb. However,

such weapons cannot be built by parties who do not already possess fission weapons, and possession of tritium will not provide any

assistance to a party that is trying to develop fission weapons.

22A fission/fusion hybrid reactor would incorporate a blanket designed specifically to breed (and/or utilize) fissionable fuel. Proliferation concerns for hybrids are therefore considerably more serious than those for pure fusion reactors.

zjThe Plutonium procfuced in a fission reactor consists Of a m iXture of different isotopes whose relative proportions depend on how

long the original uranium is irradiated. Any mixture of plutonium

isotopes can be used to make a nuclear explosive, but weapons

designers prefer to minimize the percentage of the heavier isotopes

that are produced when the fuel is irradiated for longer periods

of time. Therefore, short fueling cycles are preferable—but not

required—for producing plutonium usable in nuclear weapons.

Since plutonium can be produced in this manner in existing tission reactors, the International Atomic Energy Agency operates a

safeguards program to assure that production and diversion of fissionable fuel would be detected, minimizing the possibility of covert

production of nuclear weapons.
Resource Supplies

Much of fusion’s allure stems from the essentially unlimited supply of fuel. D-T fusion reactors

will require two elements—deuterium and lithium

–for fueling. Deuterium will be used as fuel

directly in the reaction chamber and lithium will

be used in the blanket to breed tritium fuel. Advanced fuel cycles discussed in chapter 4 that do

not use tritium wouId not require lithium.

It appears that domestic supplies of fusion

fuel will not constrain the development and use

of fusion power. Deuterium contained in water

is readily extractable, with each gallon of water

having the energy equivalent of 300 gallons of

gasoline. This supply offers billions of years’ worth

of energy at present consumption rates. Similarly,

domestic lithium supplies probably offer thousands of years’ worth of fuel with vastly greater

quantities of lithium contained in the oceans. Although recovering lithium from seawater is not

currently economical, it could be in the future;

fuel costs are such a small part of the cost of fusion power that lithium could become many

times more expensive without substantially affecting the cost of fusion electricity. According to a

study of fuel resources for fusion, it appears “unlikely that an absolute shortage of lithium could

constrain the prospects of D-T fusion in any time

of practical interest.”24

Preliminary studies of the materials required to

build fusion reactors also do not foresee any important materials constraints, although the preliminary nature of fusion reactor designs makes

firm conclusions impossible. In 1983, Oak Ridge

National Laboratory conducted a study that estimated a “per reactor” materials demand from

a set of fusion reactor design studies completed

in the 1970s. These estimates were converted into

annual fusion demands by assuming that in the

long run, close to 40 fusion reactors would be

built per year.25

24w.Hafele,j. F. Hold ren, and G. L. Kulcinski, ‘‘The Problem of

Fuel Resources, ” Fusion and Fast Breeder Reactors (Laxenburg, Austria: International Institute for Applied Systems Analysis, 1977), p. 32,

2jCannon, Background /nformat)on, op. cit., ch. 9. The study assumed a worldwide installed electric generating capacity of 1,500

gigawatts, or about 2.4 times the 1986 U.S. installed capacity [given

by the North American Electrlc Reliability Council, “ 1986 Electricity Supply and Demand, ” figure 8, p. 25]. Assuming this capacity

Ch. 5.—Fusion as an Energy Program “ 113

The study compared these estimates to nonfusion demand projections, based on U.S. Bureau

of Mines estimates, which were extrapolated over

a time span comparable to that assumed for the

fusion estimates. The study also compared demand estimates to estimated world supplies.

The study did not find any materials for which

total fusion demands exceeded non-fusion demands. Therefore, in those cases for which total

demand appeared to exceed available supply

when projected over many decades, overall scarcity would not be due solely to fusion. There

wouId be ample motivation other than fusion for

either identifying substitutes or finding new sources

of Supply. 26

At this stage of fusion reactor design, substitutes

can be found for any of the materials that might

be in short supply. However, replacing several

materials simultaneously, such as all those that

wouId be in short supply if foreign sources were

not available, would be much more difficult than

finding substitutes for any one material. If resource constraints affect fusion reactors, they

will concern materials for reactor construction

rather than fuel supply.

cost

Estimating the costs of fusion reactors that cannot yet be designed in detail is difficult. The task

is considerably complicated by the fact that economic projections, more than many other features discussed so far, depend critically on parameters that can be little more than guessed at

to be supplied by generating stations averaging 1 gigawatt each and

having an average lifetime of 40 years, an average of

1,500+-40= 37.5 plants would have to be replaced per year. The

study assumed that all replacements would eventually be made with

fusion reactors.

zGlbid, table 9.24, p. 9-36. Although fusion materials demand did

not constitute the majority of the total (fusion plus non-fusion) demand for any of the materials studied, fusion requirements constituted between 10 and 50 percent of the total demand for fwe

materials: beryllium, lithium, helium, tungsten, and vanadium. All

of these except tungsten were found to be in ample supply.

Fusion demands were calculated from an ensemble of 10 dJfferent reactor designs. Such an ensemble represented a diversity of

reactor concepts, and using the ensemble kept the analysis from

being too dependent on a single design. Any individual reactor design, however, may have materials requirements significantly different from the ensemble average.
today. Many non-technical factors such as interest rates, construction time, and the licensing and

regulatory process will have a profound and unpredictable impact on ultimate cost.

Fusion will be a capital-intensive technology.

Existing system studies show that most of the cost

of electricity will come from building the powerplant. Costs for the deuterium and lithium required to fuel fusion reactors will be a negligible

fraction of the total cost. More significant as an

effective “fuel” cost will be the expense of periodically replacing the blanket components as

they exceed their service lifetimes. Even including these replacements, however, total operational and maintenance expense is projected to

constitute less than half of the total cost of fusiongenerated electricity.27

In analyzing how the costs of fusion electricity

depend on various physics and technology parameters, system designers can determine important cost drivers and identify high-payoff areas for

further research. Because of overall uncertainties,

however, the actual costs estimated in system

studies are less dependable than their variation

as design assumptions are changed. A National

Research Council report on fission/fusion hybrid

reactors 28 identifies many sources of uncertainty

in present cost estimates, including:

●

●

●

●

●

incomplete design information;

limited understanding of the required fusion

technologies, methods of fabrication, materials, and support systems, including in particular incomplete knowledge of the effects

of high-energy neutron irradiation;

complex requirements for tritium recovery

and handling, and the need for remote handling and storage of large, radioactive components;

the degree of containment facility that will

be required for the reactor and for associated tritium handling systems;

the approach taken towards licensing, including the need for in-service inspection,

27J. Sheffield, et al,, Cost Assessment of a Generic Magnetic Fusion Reactor, Oak Ridge National Laboratory, ORNL/TM-931 1,

March 1986, table 1.2, p. 7.

28NatiOnal Re5earch council, ~u[/oO& (or ~he Fusjort Hybrid and

Tritiurn-Breedirtg Fusion Reactors (Washington, DC: National Academy Press, 1987), p. 90.

●

●

seismic qualification, redundancy and diversity;

the costs of waste disposal and decommissioning; and

the life expectancies and failure modes of

plant components, which depend on the

combined effects of neutron irradiation,

magnetic fields, high temperatures, and corrosion.

Existing information on the costs of fusion experimental facilities does not necessarily provide

much guidance for estimating the future costs

of commercial reactors. No experiment to date

comes close to integrating the various systems

that would be required in an operating reactor.

Many individuals argue that the proposed costs

of future experimental facilities—an engineering

test reactor, for example, which will cost at least

$1 billion and very possibly several times that

much—do not bode well for inexpensive powerplants. However, experimental facilities and commercial devices have very different missions and

design constraints.

A number of factors would tend to make commercial facilities less expensive than experimental

devices that produce comparable amounts of

power. Experiments are necessarily based on incomplete knowledge—otherwise there would be

no need for them—and their designs must be conservative to ensure that their objectives can be

fulfilled. Experiments must be flexible; they must

have the ability to operate under a wide range

of conditions, since the operating parameters that

will be of most interest for future commercial reactors are not yet known. They must be extensively instrumented with diagnostic equipment,

since their primary objective would be to produce information, not electricity. The result of this

information and the experience with the technology acquired through the research program should

make it possible to reduce the cost of subsequent

facilities, including commercial ones.

On the other hand, a different set of factors

would tend to increase the cost of commercial

facilities over that of their experimental counterparts. Expenses may be incurred in ensuring long

life, reliability, ease of maintenance, and ease of

operation, qualities that are crucial for commer-
Ch. 5.—Fusion as an Energy Program ● 115

cial facilities but that may not be so important

for experimental devices. Many of the design features and requirements introduced in the process of licensing, optimizing, and commercializing fusion reactors will also tend to add to the

expense of commercial facilities. It is therefore

very difficuIt to draw conclusions about reactor

cost from existing experience or from the cost of

proposed experiments.

ESECOM has conducted the most extensive

analysis to date comparing costs of various fusion

designs to one another and to fission reactors.

In the ESECOM report, construction cost estimates

varied by about a factor of 2 among the fusion

designs, and the pure fission costs were similar

to or below the low fusion estimates. “Cost-ofelectricity’ estimates varied over a somewhat

smalIer range, and the fission designs again were

at the low end.

The lowest operating cost of any of the reactors

examined by ESECOM was for the “best experience” light-water reactor, representing the lowest

cost fission reactors now operating. The highest

operating cost of all designs was for the “median

experience’ light-water reactor, representing a

cross-section of present light-water reactor experience. Estimated operating costs for all the fusion

designs fell in between these cases. Construction

cost (as opposed to operating cost) estimates varied similarly, with some of the pure fusion design construction costs exceeding that of the “median experience” light-water reactor.

One feature of fusion reactor design that could

significantly affect economics is its level of safety

assurance. The easier it is to demonstrate the

safety of a fusion reactor, the easier that reactor

will be to license and site. in particular, if the

licensing process does not depend on complex

and controversial calculations concerning the

performance of active safety systems, it might proceed more quickly and with greater consensus.

If in turn the construction process were sped up,

considerable cost savings could result.

Higher degrees of safety assurance could also

have a more direct effect in reducing construction cost. Because safe operation of commercial

nuclear reactors today depends on active safety

systems, those systems must meet exacting quality

assurance standards. Components and systems

built to meet these “nuclear-grade” standards are

considerably more expensive than similar components in less critical applications. Since the

safety of reactor designs with higher levels of

safety assurance would not be as dependent on

particular components or systems, fewer “nuclear-grade” components would be required. The

ESECOM report estimated that up to 30 percent

of the “overnight” construction costs (e. g., the

total cost if construction could be completed instantaneously, not including interest charges or

inflation) could be avoided if nuclear-grade construction were not required. Such a decrease in

construction cost would lower the cost of electricity by about 25 percent. This savings is overestimated in that no fusion system is likely to be

able to avoid nuclear-grade construction entirely;

tritium-handling systems, for example, will always

have the potential to release some radioactivity

in the event of sufficient component failures.

Nevertheless, the ability to relax construction

standards through higher levels of safety assurance could lead to cost savings.

Possibly mitigating these cost savings is the

price of achieving increased safety assurance in

the first place. In the ESECOM report, the costs

of the pure fusion designs (before any savings due

to safety assurance were taken into account)

tended to be higher for those designs with higher

levels of safety assurance. The net effect of safety

assurance on reactor cost, therefore, depends on

whether savings can outweigh the price of additional design constraints.

Future technological developments could also

decrease the cost of fusion power. For example,

the recent discovery of new superconducting materials that do not require liquid helium temperatures could affect fusion design and economics

if these materials can be used in fusion magnets.

Cheaper magnets, by themselves, will not dramatically alter the price of a fusion reactor. Even

if the magnets in the STARFIRE design were free,

the total capital cost would only be reduced by

about 12 percent .29 However, if new magnet capabilities in turn make possible the use of sign if-

‘9J. Sheffield, et al,, Cost Assessment ofa Generic Magrtetlc Fusion Reactor, op. cit., tables A,4. 1 and A.4.2, pp. 84-85,
116 . Starpower: The U.S. and the International Quest for Fusion Energy

icantly different designs—e.g., the use of substantially higher magnetic fields, which could ease

the requirements on other systems or permit the

use of advanced fuels—then significantly different economic estimates might result. JO

If reactors running on advanced fuel cycles

were developed that had substantially lower

levels of neutron irradiation, blanket components

would not have to be changed as often, reducing operating costs, However, in the case of the

D3He cycle, the costs of the actual fuel would

no longer be negligible due to the expense of

generating or recovering 3He, which is not found

in nature. Capital cost for the fusion core of a reactor using advanced fuels might be higher than

lopossible appl icatic3ns of high field superconducting magnets to

fusion reactor design are discussed in Tokarnak Reactor Concepts

Using High Temperature, High Field Superconductors, by D.R.

Cohn, et al., Massachusetts Institute of Technology Plasma Fusion

Center, PFC/RR-87-5, Apr. 14, 1987.

that of a D-T reactor since the advanced reactor

technology would be considerably more challenging. On the other hand, if an advanced reactor were able to generate electricity directly,

without the use of steam generators and turbines,

it might be able to bypass some of the balanceof-plant costs.

Given all the uncertainties, OTA finds that the

economic evidence to date concerning fusion’s

cost-effectiveness is inconclusive. No factors yet

identified in the fusion research program conclusively demonstrate that fusion will be either much

more or much less expensive than possible competitors, including nuclear fission. Fusion appears

to have the potential to be economically competitive, but making reliable cost comparisons will

require additional technical research and a better understanding of non-technical factors, such

as ease of licensing and construction, that can

have a profound influence on the bottom line.

THE SUPPLY OF AND DEMAND FOR FUSION POWER

The factors that influence how successfully fusion technology will serve as a source of energy

include how well fusion’s characteristics meet the

requirements of potential customers and how

well fusion compares to alternate electricity-generating technologies. How well fusion will meet

the needs of its users, primarily electric utilities,

depends in turn both on when it can become

commercially available and on what its users

want. These issues are discussed first below. Next

is a brief summary of competing energy supply

technologies that provides some context for fusion power. Finally, the implications of estimates

of future electricity demand are analyzed.

The Availability of Fusion Power

Financial resources permitting, the research

program outlined by the Technical Planning Activity (TPA)31 and described in chapter 4 is tarllThe TeChniCal plarln~ng Activity was a fusion communitywide

effort to identify the technical issues, tasks, and milestones that characterize the remaining fusion research effort. Its primary output was

Technical Planning Activity: Final Repofl, prepared by the Argonne

National Laboratory, Fusion Power Program, for the U.S. Departgeted toward enabling a decision on fusion’s

overall potential to be made by 2005. According to TPA, if the decision is made to proceed

with fusion at that time, an “Integrated Fusion

Facility” (IFF) based on “commercially relevant

fusion technology” could be built that would

mark the “beginning of the commercialization

phase of fusion.”32 TPA did not specify the nature of the IFF. It could be a demonstration or

prototype reactor, although the IFF parameters

TPA presented in an example show it to be well

short of commercial performance (see ch. 4, footnote 28). Thus, the technical steps that might follow the research phase, in terms of the necessary facilities that would lead to a prototype

commercial fusion reactor, have not yet been determined.

The institutional process by which any demonstration fusion reactor might be built and operated is also highly uncertain. Under present Fedment of Energy, Office of Energy Research, AN L/FPP-87- 1, January 1987. The Technical Planning Activity is described in the section of ch. 4 titled “The Technical Planning Activity. ”

lzTechnica/ planning Activity: Final Report, op. c!t., PP. ~ and 26.
Ch. 5.—Fusion as an Energy Program ● 117

eral policy, building and operating a demonstration

reactor is the responsibility of the private sector,

which has certainly proven capable of demonstrating major new technologies in the past. However, involving the private sector in an effort of

this scale may not be straightforward. According

to one utility executive:

. . . there is a certain level of concern for the

enormous gap in perception that exists between

industry and government concerning private sector commercialization. It may be unrealistic to assume that once a scientific and related technology data base is established in the program, the

stage will be set for private sector commercialization of attractive fusion energy sources.33

Unless the Federal Government becomes responsible for owning and operating fusion generating stations—a change whose ramifications

would extend far beyond fusion’s development—

some mechanism for easing the transition from

government to private responsibility will be required. 34

The timing of the commercialization process

is difficult to predict for both technical and institutional reasons. Conceivably, if the research

program provides the information necessary to

design and build a reactor prototype, such a device couId be started early in the next century.

After several years of construction and several

more years of qualification and operation, a base

of operating experience could be acquired that

wouId be sufficient for the design and construction of subsequent reactors. If the regulatory and

licensing processes proceeded concurrently, vendors could begin to consider the manufacture

and sale, and utilities could consider the purchase, of commercial fusion reactors midway

through the first half of the next century.

The subsequent penetration of fusion reactors

into the energy market wouId take time because

~jKenneth L. Matson, Vice President, PSE&G [Public Service Electric & Gas Co.] Research Corp., Newark, NJ; quoted in “Panel Discussion on Industry and Utility Perspectives on Future Directions

in Fusion Energy Development, ” Journa/ of Fusion Energy, vol. 5,

No. 2, June 1986, pp. 144-145. This issue of the Journa/ of FusiorI

Energy presents an edited transcript of a symposium sponsored by

Fusion Power Associates titled “The Search for Attractive Fusion

Concepts. ”

jqFor more discussion of the role of the private sector in fUsiOn’s

development, see the section in ch. 6 on “Private Industry. ”

existing electrical generating capacity will not be

replaced overnight. If early fusion plants can be

built and operated without undue delays or surprises, they may begin to develop a satisfactory

track record that will stimulate further construction; if early plants show unfavorable operating

experience, commercialization will be delayed.

At any rate, it will take decades from their first

successful demonstration for fusion reactors to

generate a considerable fraction of the Nation’s

electricity. Even under the most favorable circumstances it does not appear likely that fusion

will be able to satisfy a significant fraction of

the Nation’s electricity demand before the middle of the 21st century.

The Desirability of Fusion Power

Ultimately, fusion’s commercial potential will

be determined by its ability to meet societal needs

more effectively than its alternatives. This determination will be made by the eventual purchasers

of fusion technology, most likely electric utilities.

However, given the long-term nature of the fusion program, it is difficult to predict what characteristics will be important to future customers.

The best that can be done is to identify those attributes that are important to utilities today, recognizing that utilities and their requirements may

evolve with time.

Certainly one of the most important factors will

be the capital cost of fusion plants and the cost

of fusion-generated electricity. Although fusion

may be economically competitive with other

energy technologies, it is not likely to be substantially less expensive. Nevertheless, without a

demonstrable economic advantage, it might be

difficult to convince potential purchasers to risk

substantial investments in what wouId be an unknown and unproven technology.

Even if fusion cannot beat its competitors economically, it still may be judged preferable on

environmental, safety, and resource security

grounds. If the potential of fusion technology in

these areas is achieved, and if these attributes are

important enough to compensate for an economic penalty, explicit policy decisions could be

made to promote fusion through legislation or

regulation. Barring such direct intervention, how-
118 ● Starpower: The U.S. and the International Quest for Fusion Energy

ever, the primary determinant of fusion’s market

penetration probably will be cost.

In addition to purely economic factors, a number of additional factors–most of them indirectly

influencing the cost of energy—are also important to present utilities. The Electric Power Research Institute (EPRI) surveyed a number of electric utilities in 1981 to determine how important

factors other than the cost of energy would be

to their acceptance of fusion. The results of the

survey are shown in table 5-2.

EPRI found that utilities identified four factors

as “vital” and ten as “very important” for future

fusion reactors. Although it is too early to evaluate how well fusion will be able to satisfy these

requirements, the potential of the technology i n

Table 5-2.—Utility Requirements Summary

(in addition to cost of energy)

Requirement Weighting

A. Utility planning and finance

1. Plant capital cost ., Vital

2. Plant O&Ma and fuel cost Important

3. Outage rates Very important

4. Plant lif e Important

5. Plant construction tim e Very important

6. Financial liability , . . Vital

7. Unit rating ~ ~ Moderately important

B. Safety, siting, and licensing

1, Plant safet y Vital

2. Flexibility of siting ~ ~ Very important

3. Waste handling and disposal .Very important

4. Decommissioning ., Important

5. Licensability. Vital

6. Weapons proliferation Important

C. Utility operations

1. Plant operating requirements Very important

2. Plant maintenance requirements Very important

3. Electrical performance . Very important

4. Capability for load change Moderately important

5. Part load efficiency . . Moderately important

6. Minimum load . . . Moderately important

7. Startup power requirements Important

D. Manufacturing and resources

1, Hardware materials availability Very Important

2. Industrial base. . . . . Very Important

3. Fuel and fertile material availability Very important

Order of significance

1. Vital

2. Very important

3. Important

4. Moderately important

No factors were judged ‘‘slightly important’; factors judged

‘‘unimportant’ have been deleted from the list. )

aOperations and maintenance

SOURCE Electric Power Research Institute Utility Requirements for Fusion EPRI AP-2254 February

1982 table 2-1 p 2-3

some areas can be noted. For example, successfully designing fusion reactors with high levels of

safety assurance could satisfy plant safety requirements, lessen financial liability 3 5

, and improve

plant licensability. In addition, if fusion reactors

could be convincingly demonstrated to be safe,

siting flexibility might be increased; reactors could

be located close to population centers on sites

that would not be considered for fission reactors.

potential advantages for fusion reactors also

emerge with respect to other utility requirements.

Due to its virtually limitless fuel supply, fusion

should be able to satisfy the fuel availability criteria. Moreover, it appears that the waste handling and disposal should be better addressed by

fusion than by fission.

A number of uncertainties remain for other factors of importance to utilities. At present, there

is virtually no industrial base for fusion, although

existing fission, aerospace, and materials industries all have capabilities relevant to fusion’s

needs. Developing fusion’s industrial base is essential if the commercialization process is to succeed. Moreover, due to uncertainties in economic studies, how well fusion will be able to

minimize plant capital cost cannot yet be determined. In addition to affecting the cost of energy

through life-cycle capital amortization, large capital expenditures can complicate corporate financial management in areas such as debt-to-equity

ratios and capital flexibility. It is clear that fusion

reactors will be capital-intensive, but at this stage

of development their costs cannot be accurately

determined.

Hardware availability, which measures the

cost, scarcity, and supply dependability of materials required for plant construction, cannot be

determined at this stage of design. Factors such

as outage rates, plant construction times, plant

operating requirements, plant maintenance re -

quirements, and electrical performance, als o

viewed as very important by utilities, probably

cannot be evaluated until fusion reactors are well

into the commercialization process. Experience

JJFinancial Ilability measures the maximum potential flnanClal

losses due to death, injury, property damage, loss of revenue, and

other costs in the event of an accident.
Ch. 5.—Fusion as an Energy Program ● 119

with construction, operation, and maintenance

of the reactors will be necessary to fully understand these aspects of fusion technology.

A factor that is interesting due to its relatively

low weighting is unit rating, or the electrical capacity of a particular generating station. In the

early 1970s, fusion reactor conceptual designs

had electrical outputs considerably higher than

those of existing generating stations. Subsequent

designs have lowered electrical capacities to

1,000 megawatts of electricity or less, more in line

with existing stations; some recent studies have

even considered fusion plants generating as little as 300 megawatts of electricity, although at

a higher projected cost of electricity.36 Now that

fusion reactor designs are sized within the range

of utility experience—together with the relative

unimportance of this parameter —fusion reactors

should have little trouble meeting unit rating requirements.

Comparisons of Long-Term Electricity

Generating Technologies

This section summarizes the long-range potential of various electricity generating technologies

in the 21st century and discusses possible problems associated with their use and/or further development. A detailed examination of the characteristics of these energy technologies, however,

is beyond the scope of this report .1’

The role of demand modification, such as conservation and improvement in the efficiency of

energy use, is critical in determining future energy

requirements. However, as shown in the following section on “Fusion’s Energy Context, ” the

level of electricity demand does not strongly affect the relative demand for fusion power comJbone study presenting cost of electricity as a fu nCtiOn Of electrical output is J. Sheffield, et al., Cost Assessment ofa Generic Magnetic Fusion Reactor, op. cit., figure 4.17, p. 48.

Jzselected OTA studies that have examined other energy technologies i n more detail include New .E/ectric Power Technologies:

Problems and Prospects i’or the 1990s, OTA-E-246 (Washington,

DC: U.S. Government Printing Office, July 1985); Nuc/ear Power

in an Age of Uncertainty, OTA-E-216 (Washington, DC: U.S. Government Printing Office, February 1984); and /ndustria/ and Comrnercia/ Cogeneration, OTA-E-192 (Springfield, VA: National Technical Information Service, February 1983).

pared to its alternatives. Therefore, improved efficiency of energy use is not specifically discussed

here as a generating technology.

Fossil Fuel Technologies

Coal.–Coal is the most abundant energy source

in the United States and is currently used to generate over half of the Nation’s electricity .38 According to the Energy Research Advisory Board:

Coal supply for the 1985-2020 period does not

seem to require any special attention at this time

. . . It has been the conventional wisdom that the

U.S. coal resource base is of such magnitude that

it can be safely relied upon to supply any demand

for the foreseeable future. This would be true

even if nuclear generation does not grow and if

a major demand for coal-based synthetics should

arise,39

Many coal technologies are highly developed

and well understood, and they are economically

attractive. Proven domestic reserves of coal are

adequate to maintain present rates of use for several hundred years. However, there are serious

environmental impacts associated with or anticipated from the combustion of coal. Mitigating

these adverse environmental impacts increases

the cost of coal combustion and may reduce the

efficiency of conversion to electricity. Furthermore, coal combustion inherently produces carbon dioxide gas, which may affect world climate

and make the use of coal undesirable.

The main near-term problem associated with

the use of coal appears to be emissions of combustion byproducts such as sulfur and nitrogen

oxides and particulate. These emissions are a

major contributing factor to acid deposition, also

called “acid rain. ” Air pollution from coal and

other fossil fuel combustion can harm natural

jBln 1985, coal generated 1,401 billion of the 2,469 billion

kilowatt-hours of electricity generated in the United States, according to Annua/ Energy Review 1985, published by the U.S. Department of Energy, Energy Information Administration, DOE/EIA0384(85), table 81, p. 185.

jqEnergy Research Advisory Board, “Appendix D: Coal Research

and Development, ” by Eric H. Reichl, Cuide/ines for DOf Long

Term Civilian Research and Development, vol. VI( Report of ERAB

Supply Subpanel, Long-Range Energy Research and Development

Strategy Study, A Report of the Energy Research Advisory Board

to the U.S. Department of Energy, DOE/S-9944, December 1985,

p. 65.
120 ● Starpower: The U.S. and the International Quest for Fusion Energy

ecosystems, damage economically important materials, impair visibility, and may affect human

health.@

The near-term environmental problems associated with coal and fossil fuel combustion,

though serious, can be controlled. The release

of combustion byproducts can be mitigated by

using cleaner fuels, attaining more complete combustion, or cleaning (“scrubbing”) the combustion exhaust. Several technologies to reduce undesirable combustion byproducts are currently

available, and more are being developed.41 Such

pollution abatement systems make coal-fired

electricity somewhat more expensive, but they

do not eliminate coal as a major source of future

electricity supply. With the exception of carbon

dioxide buildup, discussed below, issues concerning the environmental acceptability of coal

combustion are resolvable by burning cleaner

fuels or by using “clean coal” technologies.

Oil and Gas.–Oil and gas today generate substantially less electricity in the United States than

coal. 42 The domestic resource bases for oil and

gas are considerably smaller than coal’s, and for

this reason oil and gas technologies are not generally included in discussions of long-range electricity supply over the periods in which fusion

may make a major contribution.

In the nearer term, however, these fuels—particularly gas—may have an increasing role in electricity generation and may very well form part of

the mix of generating technologies at the time that

fusion reactors are first introduced. Advanced gas

turbines now under development may be highly

efficient sources of electricity emitting far less

combustion byproducts than current coal plants.

Furthermore, such turbines would produce only

about one-third as much carbon dioxide per kilowatt-hour as a coal generation plant, reducing

(but not eliminating) carbon dioxide emissions

40u .s. Congres5, Office of Technology Assessment, Ac;d Rain and

Transpotied Air Pollutants: Implications for Public Policy, OTA-O204 (Washington, DC: U.S. Government Printing Office, June 1984),

pp. 9-13.

41 Ibid., Appendix A.z: “control Technologies for Reducing SUI -

fur and Nitrogen Oxide Emissions, ” p, 152.

AZTotal use of oil and gas, however, including uses other than

electricity generation, is greater than that of coal.

as well.43 Near-term electricity generating technologies are discussed in a separate OTA assessment .44

Carbon Dioxide Buildup.–Carbon dioxide

(C02

) is formed as a byproduct of the combustion of fossil fuels–coal, oil, and gas. in the past

several decades, the amount of CO2 in the atmosphere has increased about 10 percent, largely as

a result of fossil fuel combustion. Atmospheric

carbon dioxide gas can trap some of the heat radiated from the earth instead of allowing it to escape into space. Therefore, the buildup of C02

is associated with a global warming effect, sometimes called the “greenhouse effect. ”

Increased use of fossil fuels is only one potential contributor to global warming. Other gases

released into the atmosphere, such as methane,

nitrous oxide, and chlorofluorocarbons, have

similar heat-retaining properties and may, in aggregate, contribute as much as C02 to global

warming. Moreover, the connection between fossil fuel use and global warming is influenced by

factors such as the production and use of CO,

by green plants, its absorption by the oceans, and

vegetative decomposition. Global warming is potentially a very serious problem, and the consensus within the scientific community studying

the issue is that such a warming appears inevitable if emission of C02 and other “greenhouse

gases” continues to increase. However, there is

no certainty to date about the timing and magnitude of the effect, nor about what its climatic

implications might be.

The use of fossil fuels will always produce CO2

;

there is no way to eliminate C02 as a product

of the combustion process. As noted above, however, different fossil fuels and combustion technologies produce different amounts of CO2 per

unit of generated energy. Techniques to capture

the C02 from fossil fuel combustion emissions

have been proposed, but they are generally considered to be impractical for either economic or

technological reasons. Neither is there a practical way to recover C02 and other greenhouse

qJPa~ of the reduction IS due to the higher etficlency Of these

turbines; part is due to the lower carbon content of the fuel.

AANew E/ectric power Technologies: Problems and Prospect> for

the 1990s, op. cit., chs. 4 and 5.
Ch. 5.—Fusion as an Energy Program ● 121

gases that are already in the atmosphere. The only

way to reduce CO2 emissions from fossil fuel

combustion is to curtail the combustion of fossil

fuels.

Limiting the use of fossil fuels will not be easy.

The simplest way, up to a point, would be to increase the efficiency of energy use, lessening the

growth of energy demand. Displacing fossil fuel

usage with other energy technologies will be

more difficult. Coal will continue to be a major

source of electricity for the early 21st century, and

deemphasizing its use would foreclose a substantial resource base. Oil and gas currently generate more C02 annually than coal due to their

heavier use; much of their use is in decentralized

applications such as transportation and space

heating where they will be difficult and expensive to replace.

Without government intervention, technologies

developed to reduce fossil fuel usage must be

economically preferable to succeed. Because

C O2 buildup would be a global problem, fossil

fuel combustion would have to be reduced on

a global scale. It is not clear that developing nations would be willing or able to shift from fossil

fuels to other energy sources if doing so would

impose serious economic hardship. Furthermore,

those regions of the world that might benefit from

CO2

-induced climatic change would have no incentive to reduce CO2 emissions unless they were

otherwise compensated.

Possible global warming due to carbon dioxide

buildup is a complex problem with a number of

contributing causes. It provides an incentive to

develop new technologies that can substitute for

or otherwise curtail the use of fossil fuels. However, the degree to which these new technologies

reduce fossil fuel use will depend heavily on their

economic advantages, and any reductions they

contribute to fossil fuel use will occur gradually.

Nuclear Fission Technologies

Nuclear fission currently appears to be the main

alternative to the widespread future use of coal.

The technology is well developed and relatively

well understood, and it is supported by a substantial research and development infrastructure.

In 1985, 95 nuclear powerplants produced 16

percent of U.S. electricity supply,45 and nuclear

power is likely to remain the second largest

source of domestic electricity generation (after

coal) into the 21st century. Nuclear fission may

become a more important source of electricity

if CO2 or other environmental problems require

constraint of coal combustion. The main impediments to increased use of nuclear fission appear

to be its unfavorable economics and concern

about health and safety. I n the long run, many

decades from now, fuel constraints may affect the

potential of nuclear fission unless more efficient

technology, fuel reprocessing, or fuel breeding

is instituted.

Public Acceptance.–The long-term feasibility

of nuclear fission technologies will require resolution of health and safety concerns. Nuclear

power is currently the target of widespread opposition for several reasons. Members of the public

feel that mechanisms to dispose of radioactive

wastes are inadequate to prevent the uItimate release of dangerous radioactive effluents. Moreover, there is concern about the safety of nuclear

reactors, particularly in the aftermath of the Three

Mile Island (U. S.) and Chernobyl (U. S. S. R.) accidents. The potential for mechanical failure and

operator error casts doubt on the integrity of reactor safety systems.

Economics.–The economics of nuclear power

are currently uncertain for several reasons, not

all of which are related to characteristics of the

technology. The technology is complex and demands strict quality control; nuclear plant construction requires longer lead times and greater

capital investment than coal plants. Changing regulations, inadequate management at some plants,

and time-consuming litigation add to its cost. The

combination of these factors with the soaring interest rates of the late 1970s resulted in costs

much higher than expected. Although some

plants–even in recent years–have been built on

schedule and within budget, the more common

experience has been so traumatic that utilities will

continue to be extremely cautious about undertaking new nuclear construction. Furthermore,

large-scale plants–the only type available at

present for nuclear fission–are unattractive in the
122 . Starpower: The U.S. and the lnternational Quest for Fusion Energy

situation of uncertain demand growth that utilities now face. Smaller scale, modular plants that

track load growth more flexibly are preferred in

these circumstances.

Fuel.–The light-water reactor technology currently used in fission reactors is capable of extracting only a small fraction of the energy potentially available from uranium fuel rods. In the

“once-through” fuel cycle currently in use, the

fuel rods are withdrawn from the reactor and

stored or disposed of once they become unusable.

With greatly expanded use of fission reactors of

this type, the demand for uranium would increase

and the supply of inexpensive uranium would

eventually be depleted. At some point, the price

of uranium would rise high enough to make lightwater reactor technology economically prohibitive, although current projections indicate that

such a point is not likely to be reached before

the middle of the next century. Advanced convertor reactors, which extract much more energy

from the uranium fuel, are being developed and

could extend uranium supply still further.

If the price of uranium rises too high for even

advanced convertor reactors to be economical

on a once-through fuel cycle, other fuel cycles

may be possible. These fuel cycles are sufficient

to give fission technology a very long-term resource base. However, since these cycles involve

the production, separation, and transportation of

fissionable fuel, they could increase the risk of

nuclear proliferation over that of a once-through

fission economy. (See the discussion of “Nuclear

Proliferation Potential” earlier in this chapter).

Research and Development.– It does not appear that nuclear fission technology is unusable

or necessarily uneconomical. Extensive research

is currently directed at developing advanced fission reactors that will be more acceptable to the

public and more attractive to utilities; the intent

of this research is to demonstrate that future nuclear fission reactors with very different characteristics than current plants can be a viable source

of electricity. in particular, the nuclear industry

is attempting to develop passively safe reactors

that could not release large amounts of radioactivity due to operator error or mechanical malfunction. 46 Research and development are also

focusing on making modular reactor systems,

which could be constructed with shorter leadtimes and less financial risk to the utilities, and

on developing systems that use fuel more efficiently.

The nuclear industry appears to have the potential to develop a superior advanced reactor,

and a number of designs for such powerplants

exist. However, it is less certain that public confidence in the nuclear industry will improve significantly, particularly in the near term. Without

restoring public confidence, the long-term nuclear option may be unattainable.

Renewable Energy Technologies

In addition to coal-fired and nuclear fission

powerplants, there are several renewable energy

technologies. Two well-developed renewable

technologies currently contribute significantly to

world energy supply: hydroelectric power and

conventional biomass (wood), although only the

former is used significantly to generate electricity,

Several other technologies, such as wind, unconventional biofuels, solar photovoltaics, geothermal, solar thermal, and ocean energy, may offer

significant contributions during the 21st century.47

Renewable energy sources are attractive because many of them do not require construction

of large facilities for optimal economic operation

and because their fuel supplies are continually

replenished. Other attractive features of some,

but not all, of these technologies, according to

an OTA report, “include fewer siting and regulatory barriers, reduced environmental impact,

and increased fuel flexibility and diversity.” 48

qbsuch designs have been called “inherently safe. ’ However, inherent safety in this sense differs from the usage adopted by the

ESECOM report and discussed earlier in this chapter in the section

on “Risk and Severity of Accident” under “Characteristics of Fusion Electric Generating Station s.” The ESECOM report found that

passively safe fission reactors–although having greater safety assurance than existing nuclear plants—would not attain the highest

levels of safety assurance, including the level ESECOM labeled “inherent safety. ”

47 Energy ResearchAdvisory Board, “Appendix D,” op. cit., P. 11.

daNew Electric Power Technologies, Op. cit., P. 19.
Ch. 5.—Fusion as an Energy Program ● 123

Problems associated with renewable energy

sources, however, may limit their role as major

sources of electricity. Few of the technologies are

currently economically competitive in other than

highly specialized applications. Many renewable

resources are only available intermittently, and

their availability depends on factors like the

weather and the time of day. Moreover, the availability of renewable technologies depends on

geography and climate. The average amount of

avaiIable solar energy varies significantly across

the United States, largely as a result of differing

weather conditions. Wind energy is most effectively recovered in California and Hawaii. Finally,

most renewable energy sources are diffuse, requiring central-station powerplants to occupy

more land than those using technologies such as

coal and fission. On the other hand, the diffuse

nature of renewable also makes them well-suited

for decentralized applications, which may offset

the need for large centralized facilities.

In general, both technical and economic improvements are needed to make renewable

energy technologies competitive i n the 21st century. Research is being conducted on a wide variety of approaches for harnessing these energy

sources, and significant improvements are likely.

Nevertheless, it is not expected that renewable

technologies will eliminate the need for centralstation generating technologies such as coal and

nuclear fission.

Nuclear Fusion Technology

Unlike the other supply options, nuclear fusion

is still in a pre-development stage. Much of the

technology required for generating electricity

from magnetic fusion has not been demonstrated,

and the commercial potential of fusion cannot

yet be determined.

Nuclear fusion appears to have attractive features. First, it could have significant environmental advantages with respect to other centralstation generating technologies. The fusion process does not produce CO2

, nor—with appropriate choice of materials—does it appear that radioactive waste will be as high-level or as biologically

hazardous as waste produced by nuclear fission.

Second, it appears possible to design fusion reactors that will not depend on active safety systems to prevent serious accidents; such reactors

could have a higher degree of safety assurance

than fission reactors. Finally, high levels of safety

assurance, environmental advantages, and independence from geographical constraints could

make siting a nuclear fusion powerplant considerably easier than siting a plant based on another

energy technology.

The ultimate feasibility of nuclear fusion will

not be known until the technology is developed

and can be compared with the other energy options that exist at that time. At this point, it is only

possible to make projections based on the characteristics of the technology and the research necessary to overcome problems identified to date.

Table 5-3 compares various future electricity

supply options, based on extrapolations of current technologies. On this basis, magnetic fusion

has the potential to be a very attractive energy

source. Obviously, unanticipated developments

in any of the technologies described in this table could significantly alter their future role.

Fusion’s Energy Context

The anticipated need for energy over the period

in which fusion wouId undergo commercialization will influence the urgency of fusion research

and the pace of its entry into the energy supply

marketplace. OTA convened a workshop in November 1986 to examine the factors that would

determine demand for electricity in general and

fusion in particular. Several points became clear

during the discussion:49

● The overall size and composition of electricity demand, by itself, should neither require nor eliminate fusion as a supply option. Economics and acceptability, rather

than total demand, will determine the mix

of energy technologies. If fusion technology

is preferable to its alternatives, it will be used

AqFusion Energy Context Workshop, Office of “[ethnology Assessment, Washington, DC, Nov. 20, 1986. A list of participants is given

at the front of this report.
124 ● Starpower: The U.S. and the International Quest for Fusion Energy

Table 5-3.—Comparison of Prospective Long-Range Electricity Supply Options

Energy source Advantages Disadvantages and research needs

Coal ●

Oil and gas ●

●

●

Fission ●

●

●

●

Renewable “

●

●

●

Fusion

●

●

Plentiful

Technology exists today

Safe

Technology exists today

Fewer combustion byproducts emitted than

coal

Less CO2 emitted per unit energy than coal

Plentiful

No emission of CO2

No emission of combustion byproducts

Technology exists today

Unlimited fuel supply

No net CO2 emission

Technologically simple

Modular design

Unlimited fuel supply

Potential for higher degree of safety assurance than fission

No CO2 production or combustion

byproduct emission

Substantially less hazardous nuclear waste

●

●

●

●

●

●

●

●

●

●

●

●

Near-term environmental implications require development of “clean coal technologies” or fuel substitutions that may increase the cost of energy

C O2 buildup may make increased dependence on fossil fuels undesirable

Questionable long-term resource base

Does not avoid CO2 emission

Unfavorable economics and safety concerns suggest

development of advanced reactor designs that are

smaller and passively safe

Nuclear waste disposal not yet resolved

Public confidence must be improved and may or may

not result from technical improvements

Uncertain economics and technical problems require

more R&D

Intermittence and diffuseness may make renewable

inadequate substitute for central-station power generation in arbitrary locations

Significant R&D effort required to establish technical

feasibility

Environmental and safety potential highly dependent

on design, especially on materials choice

Economic potential unknown

than fission”

SOURCE” Office of Technology Assessment, 1987.

●

to replace retired generating capacity even

if overall demand is low. If fusion proves inferior to its competitors, it may not be used

even at very high demand levels. Fuel supplies for both coal and nuclear fission are

adequate to meet high levels of demand for

at least a few hundred years without fusion.

However, late in the next century, fission

may require the use of breeder reactors.

Should fusion technology prove favorable,

rapid growth in demand would facilitate its

introduction because the opportunities for

new powerplant construction would be

greater. Nevertheless, demand alone cannot

turn an unattractive technology into an attractive one.

It is unlikely that any one technology will

take over the electricity supply market, barring major difficulties with the others. At

present, a number of supply technologies

have roughly equivalent marginal costs of

production, and all participate in the supply

mix.

● Given that technologies such as coal combustion and nuclear fission are already

commercialized, fusion will have to prove

better-not only comparable—before it can

start to displace them. The criteria on which

fusion will be judged include economic,

safety and environmental issues as well as

resource security. Advantages in one area

may, but will not necessarily, compensate

for shortcomings in another.

● Potential problems with the major technologies currently viewed as supplying electricity in the future provide incentives to develop alternate energy technologies and/or

substantially improve the efficiency of energy use. Considerable expansion of coal use

may prove undesirable due to the “greenhouse effect”; safety or proliferation concerns may similarly impair expansion of the

nuclear fission option. Over the long run, fusion could provide a substitute for these

technologies. The urgency for developing fusion, therefore, depends on assumptions of
Ch. 5.—Fusion as an Energy Program ● 125

the likelihood that existing energy technologies will prove undesirable in the future.

● There is little to be gained and a great deal

to be lost if fusion is prematurely introduced without attaining its potential economic, environmental, and safety capabilities. Even in a situation where problems

with other energy technologies urgently call

for development of an alternative source of

supply, that alternative must be preferable

in order to be accepted. It would be unwise

to emphasize one fusion feature—economics

or safety or environmental advantages—over

the others before we know which aspect will

be most important for fusion’s eventual

acceptance.

● New energy technologies take a long time

to develop and gain wide use. It currently

appears that it will be many decades before

fusion will be able to supply a significant fraction of U.S. electricity even under optimistic assumptions concerning its technological

development.

With respect to global energy demand, in particular, as a motivation for fusion, workshop participants discussed various estimates of future

energy demand. Models attempting to chart the

evolution of global energy demand over many

decades have been developed in the last few

years. Because the time periods of interest are

much too long for projections of recent experience to be valid, these models must instead simulate the future world economy and use of energy.

These models start with a number of assumptions

concerning world economic and population

growth; the relationship between economic

growth, technological development, and energy

use; and the resource bases and costs of various

energy technologies. The models calculate the

evolution of those parameters assumed to be determinants of energy use and then determine

desired outputs such as the supply and price of

various types of energy.

These models are most useful for parametric

analysis: What might be the consequences of

some set of actions? Which parameters appear

to be the most sensitive determinants of future

demand? The models are, however, much less

able to project future behavior in any absolute

sense. They are inherently simplified, and even

if they accurately reflect the behavior of the system they represent, the input data they act on

are in many cases highly uncertain.

A recent review of a number of world energy

models discusses their respective methodologies

and compares some of their results, finding that

there is more than an order of magnitude variation in their respective estimates for energy demand in the year 2050 (figure 5-3).50 The variation

resuIts largely from differing input assumptions,

as is shown by the fact that, for several of the

models, a number of different projections are

plotted based on different assumptions or different sets of input data. Nevertheless, unless it is

known which assumptions are correct, even a

model known to be valid cannot produce valid

predictions.

The relative contributions of different forms of

energy supply are no better determined than the

total energy demands calculated by these models.

The costs of different supply technologies cannot be known over the periods of interest and

must be assumed. The mix of supply technologies

computed by these models therefore depends

primarily on the corresponding input assumptions. Furthermore, a detailed sensitivity analysis using one global energy model shows that

overall energy consumption figures appear to be

much more sensitive to parameters relating to

demand–e.g., relative rates of economic development and productivity growth-than to parameters describing supply technologies and costs. 5

1

This finding further reinforces the conclusion

that predictions of future energy use provide little information about the demand for any particular supply technology. The urgency for developing fusion technology, therefore, depends

on one’s assumptions as to the likelihood that

existing sources of energy supply cannot be

counted on in the future. Little justification can

be provided from demand estimates alone.

SoBill Keepin, “Review of Global Energy and Carbon DIo\Kle l+)-

jections, ” Annua/ Review of Energy, Jack Hollander, I+art m Brooks,

and David Stern llght (eds. ), vol. 11 (Palo Alto, CA: Annual Rejleih<

Inc., 1986), p. 357.

5 I j .M.Rei I!y, j .A. Ed mods, R. H. Gardner, and A. L. B ren ken, ‘‘~’ ncertalnty Analysis ot the I EA/ORAU CO1 Emlsslons Model ‘‘ Energ}f

)ourna/, vol. 8, No. 3, July 1987, pp. 1-30.
126 ● Starpower: The U.S. and the /international Quest for Fusion Energy

Figure 5-3.—Projections of Global Primary Energy

Consumption to 2050
Ch. 5.—Fusion as an Energy Program ● 127

CONCLUSIONS

Characteristics of Fusion Reactors

Fusion reactors appear to have the potential,

using only passive systems, to assure safe operation and shutdown in the event of accident, malfunction, or operator error. If this potential for

a high degree of safety assurance is realized, a

fusion reactor would be easier to certify as safe

than a reactor that depends on active safety systems, such as today’s fission reactors. Moreover,

fusion reactors do not appear likely to pose new

types of occupational hazards.

With proper choice of materials, the environmental characteristics of fusion reactors would

likely be preferable to other energy technologies.

Unlike fossil fuel combustion, fusion does not

produce carbon dioxide that could contribute to

overall global warming. Fusion reactors will produce radioactive waste, but these wastes should

be less radioactive, less hazardous, and easier to

dispose of than those from nuclear fission reactors. However, fusion reactor designs can differ by orders of magnitude in the amount of radioactive waste to be generated. In principle, waste

generation can be greatly minimized by the use

of materials that would not generate long-lived

radioactive isotopes inside a fusion reactor; such

materials must still be developed and tested. Routine radioactive emissions from fusion reactors

are expected to be insignificant.

One of the most attractive features of fusion

is its essentially unlimited fuel supply. Sufficient

deuterium is available and recoverable at low

cost from water to provide energy for billions of

years at present rates of use. The lithium needed

to breed tritium in D-T reactors is not as plentiful as deuterium, but it is nevertheless present in

sufficient quantity that supply of adequately priced

fuel is very unlikely to constrain the prospects of

D-T fusion over any time of conceivable interest. Pending detailed fusion reactor designs, other

resource requirements are harder to estimate;

however, there is no reason to believe that other

resource requirements will constrain fusion’s development.

Projections of the economics of fusion reactors

are inconclusive at this stage of fusion’s development. Existing studies tend to show the cost

of electricity from present fusion designs would

be somewhat more expensive than that of existing energy supplies. However, these studies cannot be considered definitive for a number of reasons. First, any comparisons between prospective

technologies and existing ones are highly uncertain, considering the disparate levels of development. Second, fusion’s costs are difficult to estimate

because substantial research and development

remains to be done. Technical features that may

lead to decreased fusion costs are being explored,

and the ultimate success of these features is uncertain. Alternatively, technical problems that

drive up the cost maybe encountered. More significantly, fusion’s economics will be profoundly

affected by non-technical factors— e.g., the ease

and length of the construction and licensing processes—whose impact on fusion costs is not well

understood at present. Finally, the costs for fusion’s potential competitors are uncertain.

Timetable for Fusion Power

Considering the remaining technical research

to be done and the time period needed for the

commercialization process to result in substantial market penetration, it does not appear likely

that fusion will be able to satisfy a significant fraction of the Nation’s electricity demand before the

middle of the 21st century. The degree to which

fusion is indeed able to penetrate the energy market depends on how effectively it meets the needs

of its customers in comparison with other energy

technologies. Although the needs of 21st century

utilities cannot be predicted with confidence, a

number of features desirable to utilities today can

be identified. Economic competitiveness is certainly one of the most important; other crucially

important attributes are plant capital cost, safety,

licensability, and maximum financial liability in

case of accident. Developing fusion reactors with

high degrees of safety assurance would make fusion attractive in many of these respects.

Competitors with fusion have the potential to

supply most or all of the electricity required by

the United States in the first half of the next cen-
128 ● Starpower: The U.S. and the International Quest for Fusion Energy

tury; the overall size of future electricity demand suppliers of electricity that could make fusion the

should neither require nor eliminate fusion as a technology of choice. The degree to which fusupply option. However, there are potentially sion will replace its competitors is impossible to

fundamental problems involving the alternate predict today.
Chapter 6

Fusion as a Research Program 
.

Page

Near-Term Benefits. . . . . . . . . . . . . . . . . . . . . + . . . . . . . . . . . . . . , .............131

Development of Plasma Physics . . . . . . . . . . . . . . . . . ...+..... . ...........131

Educating Plasma Physicists . . . . . . . . .....+... . .......................132

Advancing Science and Technology . . . . . . . . . . . . . . . . . . . . . . . . . . ........132

Stature ● **..****.*.***** . ***.************ .. *******~*****.. . ......133

Near-Term Benefits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ........= ...134

Magnetic Fusion Funding . . . . . . . . . . . . . . . . . ..........................134

Magnetic Fusion Personnel. . . . . . . . . . . . . . . . . . . . . . . . . . .... ............139

Participation in Magnetic Fusion Research.. . . . . . . . . . . . . . . . . . .. ... + ......140

‘Department of Energy National Laboratories . . . m +.. . . . . . . . . . . . . . . . . . . . . 140

Universities and Colleges . . . . . . . . . . . . . . . . . . . . . . . + .+....... . .......143

Private Industry . . . . . . . . . . . . . . . . . .S. ... ... .O

. ....O . ........0.0...0.147

summary and Conclusions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... .+ ......151

Figures

Figure No. Page

6-1. Federal Funding of Plasma Physics in 1984. . . . . . . . . . . . . . . . . ., ........132

62. Defense and Civilian Federal R&D Expenditures . ....................134

6-3. Major Components in Federally Funded R&O in Fiscal Year 1987. . ......135

64. Historical Component Funding Levels of Federal R&D Programs... .. ....136

6-6 MajorDOE Civilian R&D Funding at National Laboratories in

Fiscal Year1987 .**.+** ● . . . . . . . ●  4**  ● ***.... .*.**B** .***.*.. . . 141

Page

*....*. ● ✎☞☛✎✎✎ ✎ 137

.*+**.** ● .*.*.. 139

.****** .***.... 141

.*+**.. . . . . . . . . 145

,...., ● *,*... ● o 147
Chapter 6

Fusion as a Research Program

The ultimate objective of fusion research is to A complete analysis of the fusion energy program

produce a commercially viable energy source. must include the immediate, indirect benefits and

Yet, because the research program is exploring costs of the ongoing research effort, in addition

new realms of science and technology, it also pro- to its progress in reaching its long-term goal.

vides a weal h of near-term, non-energy benefits.

NEAR-TERM BENEFITS

Fusion research has provided four major nearterm, non-energy benefits. It has been a driving

force behind the development of plasma physics.

It educates plasma physicists who contribute to

fusion and other fields. It produces technologies

with valuable applications elsewhere, and it has

put the United States in a strong position in the

world scientific community.

Development of Plasma Physics

The development of the field of plasma physics

was driven by the needs of scientists working on

controlled thermonuclear fusion and space science

and exploration. In the case of fusion energy,

The simultaneous achievement of high temperatures, densities, and confinement times [needed

for a plasma to generate fusion power] required

significant improvements in forming and understanding plasmas confined by magnetic fields or

by inertial techniques.l

Thus, research conducted on the prospects of fusion energy necessitated concurrent advances in

the area of plasma physics, and, in fact:

The international effort to achieve controlled

thermonuclear fusion has been the primary stimulus to the development of laboratory plasma

physics. 2

The field of plasma physics has synthesized

many areas of physics previously considered distinct disciplines: mechanics, electromagnetism,

thermodynamics, kinetic theory, atomic physics,

1 National Research Council, Physics Through the 1990s: F%srnas

and F/uids (Washington, DC: National Academy Press, 1986), p. 5.

~lbid.

and fluid dynamics. Today, plasma physics goes

beyond fusion research. Since most known matter in the universe is in the plasma state, plasma

physics is central to our understanding of nature

and to the fields of space science and astrophysics.

Theories and techniques developed in plasma

physics are providing fundamental new insights

into classical physics and are opening up new

areas of research.

The field of plasma physics has grown rapidly

since the 1950s. When the American Physical Society formed the Division of Plasma Physics in

1958, for example, the division had less than 200

members. Today, the Division of Plasma Physics

is one of the society’s biggest groups, with almost

3,400 members. The careers of most of these

members originated in magnetic fusion-related

work. In addition, over 40 American universities

now have major graduate programs in plasma

physics and/or fusion technology. Graduate level

plasma physics courses are also taught in applied

mathematics and in electrical, nuclear, aeronautical, mechanical, and chemical engineering departments.

As shown in figure 6-1, the Department of

Energy (DOE) has played a major role in plasma

physics research, funding over three-quarters of

federally sponsored plasma physics research in

fiscal year (FY) 1984. Virtually all DOE support

was directed at fusion applications; 72 percent

of DOE’s funding was dedicated to the magnetic

fusion program, 26 percent funded the inertial

confinement fusion program, and only 2 percent

($3 million, in 1984 dollars) was directed at general plasma physics. Outside of the fusion applications, Federal funding for plasma physics

131
132 ● Starpower: The U.S. and the International Quest for Fusion Energy

Figure 6-l.— Federal Funding of Plasma Physics

in 1984

NOAA (0.2°/0)

research is very limited. A National Research

Council report concluded that “support for basic

plasma physics research has practically vanished

in the United States, ” with only the National Science Foundation providing funds “clearly for this

purpose.” 3

Educating Plasma Physicists

Educating plasma physicists, as well as other

scientists and engineers, is one of the most widely

acknowledged benefits of the fusion program.

Over the last decade, DOE’s magnetic fusion

program has supported the education of almost

all of the plasma physicists trained in the United

States. 4 This achievement is due largely to DOE’s

commitment to maintaining university fusion programs during a period when budget reductions

have forced other agencies to curtail their funding of plasma physics research. In addition, DOE

provides 37 fusion fellowships annually to qualified doctoral students.

Jlbid., p. 97.

4John F. Clarke, Director, DOE Office of Fusion Energy, P/asrna

Physics Within DOE and the Academy Report-Physics Through

the 1990s, Department of Energy, Office of Fusion Energy, July 1986,

p. 5.

Although DOE supports the education of most

of the Nation’s plasma physics graduates, the department does not have the resources to employ

many of these people. A large fraction of the Nation’s plasma physicists are engaged in defenserelated work; 5 plasma physicists also work in

universities, private industry, and the National

Aeronautics and Space Administration (NASA)

space science program. Education in plasma

physics and fusion research enables these scientists to “make major contributions to defense

applications, space and astrophysical plasma

physics, materials science, applied mathematics,

computer science, and other fields."6

Advancing Science and Technology

Many high-technology R&D programs produce

secondary benefits or “spin -offs.” Spin-offs are

not unique to particular fields of research, since

extending the frontiers of practically any technology can lead to external applications. Although

spin-offs may benefit society, they are unanticipated results of research and should not be viewed

as a rationale for continuing or modifying hightechnology research programs. Spin-offs may not

be efficient mechanisms of developing new or

useful technologies, compared to programs dedicated specifically to those purposes. Moreover,

applications of new technologies are often drawn

from several fields and may not be attributable

to any particular one.

Over the years, fusion research has contributed

to a variety of spin-offs in other fields. While the

program cannot claim sole credit, each of the innovations listed below has at least one key element that came from the fusion program.7

‘Energy Research Advisory Board, Review of the National Research Council Report: Physics Through the 1990s, prepared by

the Physics Review Board for the U.S. Department of Energy, February 1987, p. 44.

‘Ronald C. Davidson, “Overview of Magnetic Fusion Advisory

Committee Findings and Recommendations, ” presentation to

Energy Research Advisory Board Fusion Panel, Washington, DC,

June 25, 1986.

This list is drawn from three reports: U.S. Department of Energy,

Office of Energy Research, Technology Spin-offs From the Magnet\c

Fusion Energy Program, DOE/ER-01 32, May 1982; U.S. Department

of Energy, Office of Fusion Energy, Technology Spinoffs From the

Magnetic Fusion Energy Program, DOE/ER-01 32-1, February 1984;

and U.S. Department of Energy, Office of Energy Research, The

Fusion Connection, DOE/ER-0250, October 1985. For more information about the role of these technologies and others in magnetic

fusion research, see ch. 4.
Ch. 6.—Fusion as a Research Program . 133

Contributions to Industry

Certain phenomena associated with fusion research have proven particularly applicable to the

development of electronic systems and industrial

manufacturing processes. Plasma etching is an

important process in the semiconductor industry. Fusion research has provided information

necessary to characterize and understand the

process more completely and also has contributed plasma diagnostics that can be used to monitor the etching process.

Microwave electronics is another fusion contribution that has both civilian and military applications. Microwave tubes and plasmas share

certain physical principles of operation, and advances in the understanding of basic plasma

physics have contributed to improvements in

microwave technology. The fusion program has

also fostered development of the microwave industry through its requirements for high-frequency,

high-power microwave sources, such as the gyrotron. Typical applications of microwave technology include high-power radar stations, television broadcasting, satellite communications,

and microwave ovens.

Plasma physics phenomena studied in the fusion program also have significant applications

i n the plasma coating and surface modification

of industrial materials. Plasma coating is important to the manufacturing industry because it may

enable materials to better resist wear and corrosion. Finally, fusion experimental facilities use sophisticated power-handling technologies; electric

utilities are interested in the near-term applications of these technologies.

Contributions to National Defense

Although magnetic fusion research has no direct application to military uses, the fusion program has contributed to the national defense. The

most valuable contributions are in the background

plasma physics research conducted by the fusion

program and the education of scientists that later

are hired by defense programs. in addition, many

scientific ideas and technological developments

being investigated under the Strategic Defense

Initiative (SDI) grew out of research in the fusion

program. For example, contributions made by the

magnetic fusion program in the development of

neutral beams and accelerators for free electron

lasers have been instrumental to the development

of directed-energy weapons necessary for SDI applications.

Contributions to Basic Science

Plasma physics is by now considered one of

the core areas of physics research. Advances

made in the fusion program in the understanding of plasma phenomena have been used by

NASA, the Department of Defense (DoD), and

others. Moreover, the fusion program has supported basic atomic physics research for more

than two decades in order to develop detailed

knowledge of fundamental atomic and molecular processes influencing plasma behavior.

Magnetic fusion research requires computational methods and facilities that are not available in other disciplines. Thus, the magnetic fusion program leads the way in the acquisition and

use of state-of-the-art computers. The Magnetic

Fusion Energy Computing Center’s (MFECC) system of Cray computers and the satellite network

system installed for these computers are important advances in computer technology. In addition, the fusion program has developed advanced

computational methods in order to model and

analyze plasma behavior.

Finally, fusion research has contributed to the

development of plasma diagnostic technologies

that have commercial, scientific, and defense applications. The demands of fusion research on

diagnostic instrumentation are extremely exacting. Not only are plasmas very complex phenomena, but measurements of their characteristics must be made from the outside of the plasma

so as not to affect it. Therefore, considerable development of sophisticated instrumentation has

been required throughout the history of fusion

research.

Stature

The stature of the United States abroad benefits from conducting high-technology research.

The United States has been at the forefront of fusion R&D since the program was initiated in the
134 ● Starpower: The U.S. and the International Quest for Fusion Energy

1950s. Maintaining a first-rate fusion program has grams to the United States, and has enhanced the

placed the United States in a strong bargaining reputation of the United States in scientific and

position when arranging international projects, technical programs other than magnetic fusion.

has attracted top scientists from other fusion proNEAR-TERM COSTS

Magnetic Fusion Funding Comparing Fusion to

Other Government R&D

The fusion program utilizes both financial and The Federal budget for R&D has grown steadpersonnel resources. This section analyzes the ily during the 1980s, in real terms. The bulk of

monetary cost of fusion research by providing a this growth has been driven by increases in desense of context for fusion expenditures. Fusion fense R&D spending, which almost doubled beexpenditures are compared to other government tween 1982 and 1987. Non-defense R&D has also

R&D programs and to energy R&D programs in grown, though only 15 percent over the same

particular. period (see figure 6-2).

Figure 6-2.-Defense and Civilian Federal R&D Expenditures (in current dollars)

1982 1983 1984 1985 1986 1987

(estimate)

1988

(request)

Year

■ Defense ❑ Civilian
Ch. 6.—Fusion as a Research Program ● 135

Figure 6-3.–Major Components in Federally

Funded R&D in Fiscal Year 1987

The next largest identifiable blocks of Federal

R&D funding, each of approximately equal size,

are space, health, energy, and general science

research. Space activities are conducted by NASA.

Most health-related research is conducted by the

Department of Health and Human Services,

through the National Institutes of Health (NIH).

Most general science research is carried out by

the National Science Foundation (NSF) and DOE’s

high energy physics and nuclear physics programs. DOE conducts most Federal energy R&D;

the Nuclear Regulatory Commission and the Environmental Protection Agency also conduct limited energy research.

Those Federal R&D programs with budget authority estimated at over $200 million in FY 1987

are listed in table 6-1.8 The intent of this table is

to provide a context for the fusion program by

depicting its relative funding commitment. The

table is not intended to compare the magnetic

fusion program to other programs, because the

programs listed are not directly comparable.

Some are near-term efforts; others—like fusion—

are very long-term. Some, also like magnetic fusion, are focused on a single primary application;

others, like the cancer research conducted by

NIH, encompass a wide range of smaller subprograms. The balance between research and development varies considerably as well. DoD’s

large research, development, and testing programs include a small amount of research and

a great deal of development and testing, whereas

NSF’s programs, for example, are almost entirely

pure research.

As the table shows, the largest Federal R&D

programs are defense-related. Magnetic fusion is

DOE’s fifth largest R&D program, following weapons R&D and testing, naval reactor development,

high energy physics, and basic energy sciences.

Although table 6-1 provides a sense of scale between magnetic fusion research and other Federal R&D programs, it cannot be used to compare the programs themselves or the decisions

by which these programs are funded. The criteria

by which funding decisions are made in different agencies and departments are not consistent,

and the degree of competition for funds between

programs–either within a specific office or between offices, agencies, or departments—is difficult to measure. The budgets of different programs are prepared separately within the executive

branch and considered separately in Congress.

8A distinction is made between Budget Authority and Budget Outlay. Budget authority denotes how much a program could spend.

In some cases, however, actual budget outlays (what the program

did spend) will differ from the budget authority. A program may

spend less than its budget authority, or more if it has accrued saw

ings from previous years.
136 . Starpower: The U.S. and the International Quest for Fusion Energy

Figure 6=4.—Historical Component Funding Levels of Federal R&D Programs (in currant dollars)

Energy Space Health

Overall comparisons of one program to another

are typically made only at the highest levels of

aggregation, if at all.

In addition, this table does not represent a complete picture of all research undertaken by the

U.S. economy. It only measures Federal investments, and in many programs there is substantial

private sector involvement. Total private sector

investment in R&D activities for 1987 is estimated

at $60 billion, about the same as Federal R&D

investment for that year. g

gNational Science Foundation, Division of Science Resources

Studies, Science and Technology Data Book 1987 (Washington,

DC: National Science Foundation, 1986), NSF-86-31 1, figure 1, p. 3.

Comparing Fusion to Energy R&D

Since 1980, significant shifts in the emphasis

of DOE appropriations have occurred. The department has focused more heavily than it did

previously on atomic energy defense activities

and less heavily on activities conducted by civilian programs, while overall DOE appropriations

have decreased. Thus, civilian programs have

competed for a smaller piece of a shrinking pie,

resulting in serious financial pressure on civilian

energy R&D. This shrinkage is in large part due

to the Reagan Administration policy that development of near-term technology for civilian applications is better left to the private sector.
Ch. 6.—Fusion as a Research Program ● 137

Table 6-1 .—Federally Funded R&D Programs With Budget Authority Over $200 Million in Fiscal Year 1987

Fiscal year 1987 Fiscal year 1987

Research and development budget estimatea Research and development budget estimatea

program name ‘ (millions) program name (millions)

Department of Defense . . . . . . . . . . . . . .

Army . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Navy . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Air Force . . . . . . . . . . . . . . . . . . . . . . . .

Defense agencies . . . . . . . . . . . . . . . . .

Strategic Defense Initiative. . . . . . . . .

Defense Advanced Research

Projects Agency . . . . . . . . . . . . . . .

Office, Secretary of Defense. . . . . .

Defense Nuclear Agency . . . . . . . . .

National Aeronautic and Space

Administration . . . . . . . . . . . . . . . .

Space Station . . . . . . . . . . . . . . . . . . . .

Space Transportation Capability

Development . . . . . . . . . . . . . . . . . .

Space Science and Applications . . . .

Physics and Astronomy . . . . . . . . . .

Planetary Exploration ., . . . . . . . . . .

Environmental Observations . . . ., .

Aeronautics and Space

Technology . . . . . . . . . . . . . . . . . .

Aeronautical research and

technology . . . . . . . . . . . . . . . . . . .

Department of Energy . . . . . . . . . . . . . . .

Energy Supply R&D . . . . . . . . . . . . . . .

Basic Energy Sciences . . . . . . . . . .

Magnetic Fusion . . . . . . . . . . . . . . . .

Nuclear Energy . . . . . . . . . . . . . . . . .

General Science and Research . . . . .

High Energy Physics . . . . . . . . . . . .

Nuclear Physics . . . . . . . . . . . . . . . .

Atomic Energy Defense Activities . . .

Weapons R&D and Testing . . . . . . .

Naval Reactors Development . . . . .

$ 38,374.5

($ 4,754.6)

($ 9,381.9)

($ 15,416.8)

($ 7,185.5)

[$ 3,743.4]

[$ 785.2]

[$ 569.1]

[$ 306.0]

$ 3,127.7

($ 420.0)

($ 495.5)

$ 1,552.6)

552.8]

[$ 358.4]

[$ 320.9]

($ 592.0)

[$ 376.0]

$ 5,561.1

($ 1,498.6)

[$ 470.6]

[$ 345.3]

[$ 325.9]

($ 716.8)

[$ 499.7]

[$ 217.1]

($ 2,785.7)

[$ 1,882.2]

[$ 563.8]

Department of Health and Human

Services . . . . . . . . . . . . . . . . . . . . . .

Alcohol, Drug Abuse and Mental

Health Administration . . . . . . . . . .

General Mental Health . . . . . . . . . . .

National Institutes of Health . . . . . . .

Cancer . . . . . . . . . . . . . . . . . . . . . . . .

Heart, Lung, and Blood . . . . . . . . . .

Allergy and Infectious Diseases. . .

Diabetes, Digestive and Kidney

Diseases . . . . . . . . . . . . . . . . . . . . .

Neurological and Communicative

Diseases and Stroke . . . . . . . . . . .

Child Health and Human

Development . . . . . . . . . . . . . . . . . .

Eye . . . . . . . . . . . . . . . . . . . . . . . . . . .

Environmental Health Sciences . . .

National Science Foundation . . . . . . . . .

Mathematical and Physical

Sciences. , . . . . . . . . . . . . . . . . . . .

Biological, Behavioral, and Social

Sciences . . . . . . . . . . . . . . . . . . . . .

Geosciences . . . . . . . . . . . . . . . . . . . . .

Department of Agriculture. . . . . . . . . . . .

Agricultural Research Service . . . . . .

Cooperative State Research Service .

Department of Interior . . . . . . . . . . . . . . .

Geological Survey. . . . . . . . . . . . . . . . .

Department of Transportation . . . . . . . .

Department of Commerce . . . . . . . . . . . .

National Oceanic and Atmospheric

Administration . . . . . . . . . . . . . . . .

Environmental Protection Agency . . . . .

Veterans Administration . . . . . . . . . . . . .

Agency for International

Development . . . . . . . . . . . . . . . . .

$

($

[$

($

[$

[$

[$

[$

[$

[$

[$

[$

$

($

($

($

(:

($

(:

$

$

($

$

$

$

6,709,8

569.4)

307.5]

5,853.2) b

1,371 .5]

891 .2]

535.6]

488.2]

476.5]

352.5]

211 .1]

200.4]

1,520.3

463.4)

257.7)

284.6)

1,027.5

523.3)

300,3)

362.2

208.6)

285.2

401.6

287.5)

343.4

225.3

224.2

aValues denoted with "( )" comprise programs included within the preceding department total. and values denoted with “[ ]“ comprise subprograms included within

the preceding program total Only departments, programs, and subprograms with an annual budget over $200 million are listed; therefore, the listed program and

subprogram budgets may not total the preceding departmental or program budget

bTotal program budget given for the National Institutes of Health Includes an overall reduction of $67.1 million, which has not been allocated among individual Institute

subprogram budgets in these figures

SOURCE American Association for the Advancement of Science, Intersociety Working Group, AAAS Report Xll: Research and Development FY 1988 (Washington, DC

American Association for the Advancement of Science, 1987)

Though magnetic fusion has fared better than

many other energy programs, its budget has

fallen significantly in recent years. From a peak

of $659.7 million in FY 1977 (in 1986 dollars),

funding for the fusion program has declined by

over half, to a level of $319.1 million in FY 1987

(in 1986 dollars) .10 Figure 6-5 illustrates the recent

budgets of DOE’s larger energy R&D programs.

—..—I t)gud~et \ alues and I nflatlon i nd Ices were pro~lded by J. Ronald

Young, Director of the Ot’t’lce ot Management, U.S. Department

Unlike short-term energy development, the

long-term, high-risk nature of the fusion energy

program satisfies the criteria of the Reagan Administration’s science and technology policy.

Long-term, research-oriented programs like fusion have been able to maintain Federal budgetary support because, although there is a potentially high payoff, there is currently little incentive

— -—. .

of Energy, Off Ice of Energy Research, letter to the Office of Technology Assessment, Aug. 15, 1986.
138 . Starpower: The U.S. and the International Quest for Fusion Energy

Figure 6-5.—Annual Appropriations of DOE Civilian R&D Programs (in current dollars)

3.2

I

0.6

0.4

0.2

0

for industrial involvement. Even if the risks were The most expensive fusion projects to date are

not high, the benefits are so far off that their

present value is not sufficient to interest private

investors today. Virtually all fusion research is

funded by the Federal Government. DOE’s programs in nuclear energy, fossil fuels, conservation, and renewable energy, on the other hand,

have lost much of their Federal support because

it is believed that industry financing is appropriate in these cases.

Costs of Fusion Facilities

Table 6-2 lists the total construction costs of

some representative fusion program experiments.11

I I For information about the technical details of many of these

projects, see ch. 4.

the Tokamak Fusion Test Reactor (TFTR) and the

Mirror Fusion Test Facility (MFTF-B), which are

an order of magnitude more expensive than other

confinement experiments. In part, TFTR and

MFTF-B were more expensive than other experiments because they required development of an

extensive supporting infrastructure as well as construction of the actual device. In addition, these

facilities are more advanced and much larger

than the experiments constructed on alternative

concepts.

The next facility the U.S. fusion program plans

to construct, the Compact Ignition Tokamak

(ClT), has an estimated cost of $360 million. It

is proposed to be built at Princeton Plasma Physics
Ch. 6.—Fusion as a Research Program ● 139

Table 6-2.—Cost of Representative Fusion Experiments

Construction cost

Experiment Location Type (millions of 1987 dollars)

Tokamak Facility Test Reactor. . . . . . . . . . . . . . . . . . . . . . . . . . . PPPL Tokamak $562

Mirror Fusion Test Facility-B . . . . . . . . . . . . . . . . . . . . . . . . . . . . LLNL Tandem Mirror $330

Doublet Ill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .GA Tokamak $ 56a

Doublet III-D (Upgrade) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .GA Tokamak $ 36a

International Fusion Superconducting Magnet Test Facility . . .ORNL Magnet Testb

$ 36C

Poloidal Divertor Experiment , . . . . . . . . . . . . . . . . . . . . . . . . . . . PPPL Tokamak $ 5 4

Princeton Large Torus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PPPL Tokamak $ 4 3

Tritium Systems Test Assembly . . . . . . . . . . . . . . . . ... ... ...LANL Tritium Testb

$ 2 6

Tandem Mirror Experiment . . . . . . . . . . . . . . . .. .. .. ... ... ...LLNL Tandem Mirror $ 24

Tandem Mirror Experiment Upgrade . . . . . . . . . . . . . . . ... ... .LLNL Tandem Mirror $ 2 3

Texas Experimental Tokamak . . . . . . . . . . . . . . . . . . . . ... .....UT Tokamak $ 21

Advanced Toroidal Facility . . . . . . . . . . . . . . . . .. .. ... ... ... .ORNL Stellarator $ 21

TARA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... .., ..MIT Tandem Mirror $ 19

ZT-40 . . . . . . . . . . . . . . . . . . . . . . . . .. .. .. .. .. .. .. ... ... ... .LANL Reversed-Field Pinch $ 1 7

Alcator C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .. ... ... ... ..MIT Tokamak $ 15

Rotating Target Neutron Source . . . . . . . . . . . . . . . ... ... ... .LLNL Materials Testb

$ 1 1

Impurity Studies Experiment-B . . . . . . . . . . .. .. .. .. ... ... ...ORNL Tokamak $ 5

Field Reversed Experiment-C . . . . . . . . . . .. .. .. .. ... ... ... .LANL Field-Reversed $ 3

Configuration

Phaedrus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....UW Tandem Mirror $ 1.8

Macrotor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... ... ... .UCLA Tokamak $ 1.5

IMS . . . . . . . . . . . . . . . . . . . . . . . . . . .. .. .. .. .. .. ... ... .....UW Stellarator $ 1.4

Tokapole . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... .....UW Tokamak $ 0.6

KEY PPPL—Princeton Plasma Physics Laboratory, Princeton, New Jersey

LLNL—Lawrence Livermore National Laboratory, Livermore, California

ORNL—Oak Ridge National Laboratory, Oak Ridge, Tennessee

GA—GA Technologies, Inc. San Diego, California

LANL—Los Alamos National Laboratory, Los Alamos, New Mexico

UT—University of Texas, Austin, Texas

MlT—Massachusetts Institute of Technology, Cambridge, Massachusetts

UW—University of Wisconsin, Madison, Wisconsin

UCLA—University of California, Los Angeles, California

aValues shown for the combined Doublet III facility and upgrade do not Include an additional $54 million (in current dollars) of hardware provided by the government

of Japan or $36 million (in 1987 dollars) for a neutral beam addition

bThese facilities are fusion technology facilities; all others on the table are confinement physics experiments.

CThe cost of this facility does not include the cost of the six magnet coils that are being tested there. It is estimated that the magnet coils cost between $12 million

and $15 million each (in current dollars)

SOURCE US Department of Energy, Office of Fusion Energy, 1987

Laboratory, where it can take advantage of the

Iab’s existing infrastructure. With initial construction funds requested in the FY 1988 DOE budget, CIT will be the largest fusion project undertaken in recent years.

Looking beyond CIT, the U.S. fusion program

sees a next-generation engineering test reactor

as necessary during the 1990s. Funding for this

device, which is projected to cost well overabilIion dollars, has not been requested by or appropriated to DOE. A recent DOE proposal to undertake international conceptual design and

supporting R&D is currently being considered.

lf successful international construction and operation of the device couId follow the design phase

of the project (see ch. 7).

Magnetic Fusion Personnel

The fusion program currently supports approximately 850 scientists (almost all Ph.D.s), 700

engineers, and 770 technicians.12 These researchers work primarily at the national laboratories and

in the university and college fusion programs. Because the size of the labor pool responds to shifts

in the demand for labor, and because the longterm value of having a person work on one proI ZThOrna5 G. Finn, u. S. Ckpa rtment of Energy, Office Of Fu SiO n

Energy, letter to the Office of Technology Assessment, Mar. 12,

1987. The number of technicians represents only full-time staff associated with experiments; shop people and administrative staff are

not included. Figures for scientists and engineers include u n ive rsity professors and post-doctoral appointments; graduate student

employees are not included.
140 ● Starpower: The U.S. and the International Quest for Fusion Energy

gram as opposed to any other is difficult to measure, it is hard to quantify the implications of

dedicating scientific and engineering manpower

to the fusion program. The value of the fusion

program for training plasma physicists, however,

cannot be denied. The fusion program trains far

more people than it employs, and these people

make valuable contributions in a variety of fields

other than fusion.

According to DOE, since 1983 the number of

Ph.D. staff positions at the major national fusion

research centers has declined by almost 20 percent. Personnel levels among individuals without Ph.D.s, and the staffs of smaller fusion research centers, have also declined substantially.

A recent study for the National Academy of Sciences predicts that if recent funding trends continue, the fusion program could lose 345 Ph.D.s

between 1985 and 1991. Most fusion researchers who have left the fusion program have found

work easily in other research programs within

DOE and DoD. Many former fusion researchers

are working on SDI. As the mobility of fusion researchers shows, these individuals have skills that

are in demand in many areas.

PARTICIPATION IN MAGNETIC FUSION RESEARCH

DOE’s Office of Fusion Energy (OFE) funds research conducted by three different groups: national laboratories, colleges and universities, and

private industry. Each of these groups has different characteristics, and each plays a unique role

in the fusion program.

Department of Energy National

Laboratories

DOE’s national laboratories play an important

role both in the fusion program and in the department’s general energy R&D. Figure 6-6 depicts

DOE’s distribution of laboratory funding among

various subject areas. A list of DOE’s major national laboratories, showing the extent of their

fusion participation, is shown in table 6-3.

National laboratories are generally governmentowned, contractor-operated facilities. Most of

them were created during or shortly after World

War II to conduct research in nuclear weapons

and nuclear power development. Four DOE national laboratories have major research programs

in magnetic fusion. It is estimated that these laboratories will conduct over 70 percent of the magnetic fusion R&D effort in FY 1987. According to

DOE, the laboratories “are a unique tool that the

United States has available to carry on the kind

of large science that is required to address certain problems in fusion. ” It is expected that the

13john F, Clarke, Director, DOE Off Ice of Fusion Energy, ‘ ‘planning for the Future, ’ /ourna/ of Fuwon Energy, vol. 4, nos. 2/3, June

1985, p, 202.

involvement of the national laboratories in the

research program will remain important at least

until the technology is transferred to the private

sector for commercialization. The four major fusion laboratories are described below, in decreasing order of their share of the FY 1987 fusion

budget.

Princeton Plasma Physics Laboratory

The Princeton Plasma Physics Laboratory (PPPL),

located in Princeton, New Jersey, is one of the

fusion program’s oldest and most important facilities. It is located on Princeton University’s

James Forrestal Campus, and, in FY 1987, PPPL

is estimated to receive the largest share of DOE’s

magnetic fusion budget of any single institution

(27 percent).14 PPPL is a program-dedicated laboratory, which means that virtually all of its research involves magnetic fusion. The bulk of

PPPL’s budget is used to operate TFTR, the largest

U.S. tokamak experiment. TFTR is one of two

operational experiments in the world designed

to burn D-T fusion fuel, the other being the European Community’s Joint European Torus. 15 In

addition to TFTR, PPPL operates other smaller

tokamak experiments.

laBased on U.S. Depaflment of Energy, FY 1988 Congression Budget Estimates for Lab/Plant, January 1987.

Is prl nceton plasma physics Laboratory, A n Overview. Princeton

P/asrna Physics Laboratory, April 1985, p. 5. For more information

on TFTR and other experiments, see ch. 4.
Ch. 6.—Fusion as a Research Program c 141

Figure 6-6.—Major DOE Civilian R&D Funding at

National Laboratories in Fiscal Year 1987

Lawrence Livermore National Laboratory

In FY 1987, it is estimated that Lawrence Livermore National Laboratory (LLNL), located in

Livermore, California, will receive 15 percent of

Table 6.3.—DOE’S Major

DOE’s magnetic fusion energy budget.16 LLNL has

concentrated on tandem-mirror systems, and

most of the experimental facilities at the laboratory have explored the capabilities of this confinement scheme.17 The major magnetic fusion

facility at LLNL is MFTF-B, a project that was

moth balled in 1986, due to budget cuts, just

weeks after construction was completed; MFTFB has never operated. In addition to MFTF-B,

there is another significant tandem-mirror facility at LLNL—the Tandem Mirror Experiment Upgrade (TMX-U), which has also been terminated.

LLNL is now installing a small tokamak experiment and has been given responsibility for the

design of the next-generation engineering test reactor. LLNL also operates the Magnetic Fusion

Energy Computing Center for DOE. Moreover,

LLNL conducts the largest component of the Nation’s inertial confinement fusion research programs (see app. B).

IGBased on U.S. Department of Energy, FY 1988 congressional

Budget Estimates, op. cit.

1 TFor technical information on the tandem m i rror configuration,

see ch. 4.

National Laboratories

Laboratory Location

Ames Laboratory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Ames, IA

Argonne National Laboratory. . . . . . . . . . . . . . . . . . . . . . .Argonne, IL

Bettis Atomic Power Laboratory . . . . . . . . . . . . . . . . . . . .West Mifflin, PA

Brookhaven National Laboratory. . . . . . . . . . . . . . . . . . . .Upton, NY

Fermi National Accelerator Laboratory . . . . . . . . . . . . . . Batavia, IL

Hanford Engineering Development Laboratory. . . . . . . . Richland, WA

Idaho National Engineering Laboratory . . . . . . . . . . . . . . Idaho Falls, ID

Knolls Atomic Power Laboratory . . . . . . . . . . . . . . . . . . .Schenectady, NY

Lawrence Berkeley Laboratory . . . . . . . . . . . . . . . . . . . . . Berkeley, CA

Lawrence Livermore National Laboratory . . . . . . . . . . . . Livermore, CA

Los Alamos National Laboratory. . . . . . . . . . . . . . . . . . . . LOS Alamos, NM

Mound Laboratory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Miamisburg, OH

Nevada Test Site . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mercury, NV

Oak Ridge National Laboratory . . . . . . . . . . . . . . . . . . . . . Oak Ridge, TN

Pacific Northwest Laboratory . . . . . . . . . . . . . . . . . . . . . . Richland, WA

Paducah Gaseous Diffusion Plant . . . . . . . . . . . . . . . . . . Paducah, KY

Pinellas Plant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .St. Petersburg,

Portsmouth Gaseous Diffusion Plant. . . . . . . . . . . . . . . . Piketon, OH

Princeton Plasma Physics Laboratory . . . . . . . . . . . . . . . Princeton, NJ

Rocky Flats Plant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Golden, CO

Sandia National Laboratory . . . . . . . . . . . . . . . . . . . . . . . .Albuquerque, NM

Savannah River Plant . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Aiken, SC

Stanford Linear Accelerator Laboratory . . . . . . . . . . . . . .Stanford, CA

KEY: None - No magnetic fusion funding.

Minor - Fusion funding is less than $10 million in fiscal year 1987.

Major - Fusion funding is more than $10 million in fiscal year 1987.

SOURCE: Office of Technology Assessment, 1987.

Magnetic

fusion research

None

Minor

None

None

None

Minor

Minor

None

Minor

Major

Major

None

None

Major

Minor

None

None

None

Major

None

Minor

None

None
Oak Ridge National Laboratory

Oak Ridge National Laboratory (ORNL), located

in Oak Ridge, Tennessee, conducts research

across the full range of magnetic fusion program

activities and is actively involved with national

and international cooperation in virtually every

area. The Advanced Toroidal Facility (ATF), when

complete, will be ORNL’s main experiment in

toroidal confinement. It is anticipated that ATF,

a stellarator, will make important contributions

to the improvement of toroidal systems by increasing the understanding of fundamental confinement physics.18 Contributing to this understanding are other ORNL programs in theory,

diagnostics, and atomic physics The ORNL technology program is fusion’s largest, and it includes

plasma heating and fueling, superconducting

magnets, materials, and environmental assess-

— — ..-. description the confine-

 concept.

ment programs. In addition, ORNL is the host for

the Fusion Engineering Design Center, which supports both reactor and next-generation device

studies throughout the program. It is estimated

that ORNL will receive about 15 percent of the

magnetic fusion energy program’s budget in FY

1987.19

Los Alamos National Laboratory

Los Alamos National Laboratory (LANL) is located in Los Alamos, New Mexico, and it contributes to DOE’s fusion energy program in several

ways. LAN L has focused on alternative concepts.

These concepts, not as far developed as the tokamak or mirror, are studied in several experiments

at Los Alamos that are smaller and therefore less

expensive than the large tokamak and mirror ma-

 of Energy, 1988 

mates, op. cit.
Ch. 6.—Fusion as a Research Program “ 143

Photo credit: Oak Ridge National Laboratory

Assembly of The Advanced Toroidal Facility at Oak Ridge National Laboratory.

chines. 20 In addition, LANL conducts research in

fusion technology and materials, studies reactor

systems, and operates the Tritium Systems Test

Assembly (TSTA)—a prototype of the tritiumhandling apparatus necessary to fuel a D-T fusion

reactor. In FY 1987, LANL will receive about 7

percent of the magnetic fusion energy program’s

budget .21

 t. h. 4 tech n information o n a Iterative CO 

ment concepts. Congressional Budget 

mates, op. cit.

Universities and Colleges

Role in the Research Program

Universities and colleges contribute to many

areas of energy research, including magnetic fusion. The role of these programs in fusion R&D

activities differs significantly from the role of the

national laboratories. Universities and colleges

provide education and training and have been

historically a major source of innovative ideas as

well as scientific and technical advances. These

programs could not replace the national labora-

Ch. 6.—Fusion as a Research Program c 145

cepts. Overall, the Magnetic Fusion Advisory University and college fusion programs also eduCommittee (MFAC) Panel V found: cate the young researchers in the field.

The contributions from university-based exper- table 6-4 lists the university and college fusion

imental programs over the past decade have been programs. It is estimated that these programs colsignificant, obviously cost-effective and have had Iectively will receive over 14 percent of the maga major impact on the development of fusion netic fusion budget in FY 1987 directly from DOE.

energy in general, and the large-scale or “main- In addition, university and college fusion pro- Iine” experiments at the national laboratories in

particular. 22 grams could receive another 2 to 3 percent of

zzMagnetic Fusion Advisory Committee Panel V, Princi~a/ Find- the Fusion Program, July 1983, p. 18. The Magnetic Fusion Adviings and Recommendations of the Magnetic Fusion Advisory Com- sory Committee is a committee of fusion scientists and engineers

mitteeSubpanel Evaluating the Long-Term Role of (Universities in that provide technical advice to DOE’s Office of Fusion Energy.

Table 6-4.—Universities and Colleges Conducting Fusion Research

in Fiscal Years 1983 and 1986 (in 1986 dollars)

Fiscal year 1983 Fiscal year 1986

University or college budget authority budget authority

--- - . . . . Massachusetts Institute of Technology . . . . . . . .

University of Texas . . . . . . . . . . . . . . . . . . . . . . . . . .

University of California—Los Angeles . . . . . . . . .

University of Wisconsin . . . . . . . . . . . . . . . . . . . . . .

University of Maryland . . . . . . . . . . . . . . . . . . . . . . .

New York University . . . . . . . . . . . . . . . . . . . . . . . . .

Columbia University . . . . . . . . . . . . . . . . . . . . . . . . .

University of Washington . . . . . . . . . . . . . . . . . . . .

Cornell University . . . . . . . . . . . . . . . . . . . . . . . . . . .

University of California—Berkeley . . . . . . . . . . . . .

Johns Hopkins University . . . . . . . . . . . . . . . . . . . .

University of California—Irvine. . . . . . . . . . . . . . . .

Rensselaer Polytechnic Institute . . . . . . . . . . . . . .

California Institute of Technology . . . . . . . . . . . . .

Georgia Institute of Technology. . . . . . . . . . . . . . .

Pennsylvania State University. . . . . . . . . . . . . . . . .

University of California—Santa Barbara . . . . . . . .

University of Illinois . . . . . . . . . . . . . . . . . . . . . . . . .

Auburn University . . . . . . . . . . . . . . . . . . . . . . . . . . .

University of Missouri . . . . . . . . . . . . . . . . . . . . . . .

University of California—San Diego . . . . . . . . . . .

Yale University. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

University of Arizona . . . . . . . . . . . . . . . . . . . . . . . .

College of William and Mary. . . . . . . . . . . . . . . . . .

University of Connecticut . . . . . . . . . . . . . . . . . . . .

Western Ontario University . . . . . . . . . . . . . . . . . . .

University of Michigan . . . . . . . . . . . . . . . . . . . . . . .

Wesleyan University . . . . . . . . . . . . . . . . . . . . . . . . .

Stanford University . . . . . . . . . . . . . . . . . . . . . . . . . .

University of lowa . . . . . . . . . . . . . . . . . . . . . . . . . . .

University of Virginia . . . . . . . . . . . . . . . . . . . . . . . .

State University of New York—Buffalo . . . . . . . . .

Dartmouth College . . . . . . . . . . . . . . . . . . . . . . . . . .

University of Colorado . . . . . . . . . . . . . . . . . . . . . . .

North Carolina State University . . . . . . . . . . . . . . .

Stevens Institute of Technology. . . . . . . . . . . . . . .

Syracuse University . . . . . . . . . . . . . . . . . . . . . . . . .

University of New York City . . . . . . . . . . . . . . . . . .

Total university and college budget . . . . . . . . .

$26.6 million

$ 6.9 million

$ 4.1 million

, $ 4.1 million

$ 1.9 million

$ 1.3 million

$ 1.1 million

$ 776,000

$ 760,000

$ 618,00 0

$ 483,000

$ 481,000

$ 353,000

$ 351,000

$ 271,000

$ 263,000

$ 241,000

$ 226,000

$ 212,000

$ 201,000

$ 175,000

$ 123,000

$ 115,000

$ 95,000

$ 90,000

$ 78,000

$ 66,000

$ 63,000

$ 60,000

$ 30,000

$ 30,000

$ 24,000

$ 14,000

—

—

—

—

—

$24.6 million

$ 5.4 million

$ 6.2 million

$ 4.8 million

$ 983,000

$ 1.1 million

$ 1.2 million

$ 708,000

$ 535,000

$ 438,000

$ 340,000

$ 147,000

$ 392,000

$ 503,000

$ 115,000

$ 97,000

$ 335,000

$ 372,000

$ 239,000

$ 240,000

$ 50,000

$ 13,000

$ 18,000

$ 80,000

—

$ 50,000

$ 13,000

—

—

$ 60,000

$ 60,000

$ 15,000

$ 101,000

$ 25,000

$52,322,000 $49,301,000

(33 programs) (30 programs)

SOURCE: Fiscal year 1983 budgets from Magnetic Fusion Advisory Committee Panel V, Principal Findings and Recommendations of the MFAC Subpanel Evaluating the Long-Term Role of Universities in the Fusion Program, July 1983, p.

9 Fiscal year 1986 budgets provided by DOE’s Office of Fusion Energy, FY 1988 Congressional Budget Contractor

Summary, Jan 16, 1987
146 ● Starpower: The U.S. and the International Quest for Fusion Energy

the fusion budget indirectly through subcontracts

from the national laboratories. The programs conducted by the universities in fusion are diverse,

varying in funding level and research area. Over

80 percent of the university programs received

less than $1 million each from DOE in FY 1986.

Recent budget cuts have seriously affected university and college fusion programs, which have

suffered larger percentage budget reductions than

the fusion program as a whole. University funding was $49.3 million in FY 1986, is estimated at

$44.7 million in FY 1987, and is requested to be

$41.7 million in FY 1988, in current dollars. The

last two figures represent percentage decreases

of 9 and 7 percent, respectively. 23 The corresponding decreases for the overall fusion budget ($361.5 million in FY 1986, an estimated

$341.4 million in FY 1987, and a requested

$345.6 million in FY 1988, in current dollars) are

6 percent and – 1 percent.

For university and college fusion programs,

DOE is the only source of financial support. NSF,

the other likely Federal support agency, does not

fund fusion research because it is considered applied, as opposed to basic, research and because

it is believed to be DOE’s area. Thus, given recent budget cuts, two-thirds of the university and

college programs have either reduced or eliminated their programs since 1983. Seven colleges

have eliminated their fusion programs, while five

new programs have been added. It is anticipated

by University Fusion Associates (UFA), an informal grouping of individual fusion researchers

from universities and colleges, that if current

funding trends continue, as many as half of the

colleges and universities will eliminate their fusion research programs between 1986 and 1989.24

DOE has stated that it intends to maintain the

university fusion budget at a constant level (corrected for inflation) and does not foresee any

need for additional programs to drop out. In any

z~lf the Massachusetts Institute of Technology (MIT), the largest

university fusion program, is not included, the university fusion budget decreases in FY 1987 and FY 1988 are 7 and 2 percent, respectively.

~qGeorge H. Mi Icy, testimony on Fisca/ Year 1987 DeParOnefrt

of Energy Authorization (Magnetic Fusion Energy), Hearings before

the Subcommittee on Energy Research and Production, House Science and Technology Committee, 99th Cong., 2d sess., vol. 5, Feb.

26, 1986, p. 103.

case, continued tight budgets and the loss of university programs reduces the ability of the fusion

program to attract and educate new researchers.

In response to the funding cuts and the narrowing of the fusion program’s scope, UFA has

recommended that “approximately 3 to 5 percent additional funding should be added back

into the fusion budget to support innovative and

new ideas.”25 According to UFA, one of the most

urgent uses of this money would be to provide

seed money to innovative research proposed by

universities, national laboratories, and private industry. UFA contends that this funding would

help preserve some of the small university programs endangered by budget cuts, as well as create the atmosphere of excitement necessary to

attract top students to the field. This idea has been

endorsed by other members of the fusion community.

Given recent budgets, university and college

fusion programs are concerned about the future

direction of DOE’s fusion program. In particular,

representatives of UFA worry that the role of university fusion programs may be difficult to preserve if the Federal fusion program becomes

more dependent on international cooperative

projects. The international activities of college

and university fusion programs are generally

small-scale, and it is not clear how these activities could fit in a collaborative engineering test

reactor effort.

University and College Activities

Universities and colleges have made contributions to fusion research in a variety of areas. In

tokamak development, university fusion programs have worked on radiofrequency heating

and current drive, boundary physics, high beta

stability, and transport of heat and particles in fusion plasmas.26 The largest university tokamak experiments are MIT’s Alcator project, the Texas

Experimental Tokamak (TEXT) experiment at the

University of Texas, and Macrotor at the University of California at Los Angeles (UCLA).

*sIbid., p. 100.

*b For more information on the tech n ica I aspects Of these cent ri

butions, see ch. 4.
Ch. 6.—Fusion as a Research Program ● 147

Photo credit: Plasma Fusion Center, MIT

The Alcator C tokamak at the Massachusetts Institute

of Technology.

In addition to tokamak research, a small group

of universities is exploring the mirror confinement

concept. The TARA facility at MIT and Phaedrus

at the University of Wisconsin are the major

university mirror experiments and, since the

moth balling of the mirror machines at LLNL, have

become the only U.S. mirror experiments. Support for university mirror programs has decreased,

however. In fact, in the budget for FY 1987, DOE

proposed elimination of funding for these university-based mirror projects. Congress has made additional funds available to keep both operational

throughout FY 1987, and it appears that Phaedrus

will remain operational throughout FY 1988 as

welI.

Several universities also study other confinement concepts for fusion reactors, including the

stellarator, compact toroid, and reversed-field

pinch. Work in these concepts is conducted at

the University of California at Irvine, UCLA, Cornell University, University of Maryland, Pennsylvania State University, University of Illinois,

University of Washington, and University of Wisconsin.

Finally, several university programs are exploring technology development and atomic physics.

Programs at the University of Arizona, Auburn

University, University of California at Santa Barbara, UCLA, Georgia Institute of Technology,

University of Illinois, MIT, University of Michigan, Rensselaer Polytechnic Institute, University

of Washington, and University of Wisconsin focus on reactor systems, materials, surface effects,

and superconducting magnets.

Private Industry

Role in the Research Program

Private industry can take a variety of different

roles in fusion research, depending on its level

of interest and the stage of development. The

most useful roles fall into three main categories.27

These categories, along with the principal functions performed in each category, are listed in

table 6-5.

Industry as Advisor.–The advisory role of private industry is filled frequently by corporate executives who are asked to help assess various

stages of program development. The principal

benefit of the advisory role is the development

of appropriate program goals. As a support services contractor, industry assigns individuals or

smalI groups to work i n direct support of a manager at DOE or at a national laboratory. Private

industry also provides members of its technical

staffs to serve on technical committees, such as

27 Argonne National Laboratory, Fusion pOw’er program, T~chnlca/ F%nning Acti\ ;ty: FirIa/ Report, commissioned by the U.S. Department of Energy, Office of Fusion Energy, AN L/FPP-87- 1, 1987

pp. 340-343.

Table 6-5.—lndustrial Roles and Functions

Roles Functions

Advisor . . . . . . . . . . . . Support services contractor

Advisory committee

Direct participant . . . Materials supplier

Component supplier and

manufacturer

Subsystems contractor

Prime contractor, project manager

Facilities operator

Customer

Sponsor . . . . . . . . . . . Research and development

SOURCE: Argonne National Laboratory, Fusion Power Program, Technical

Planning Activity: Final report, commissioned by the U S. Department

of Energy, Office of Fusion Energy, ANL/FPP-87-1, 1987, table 7-4, p

340
748 c Starpower: The U.S. and the International Quest for Fusion Energy

the Magnetic Fusion Advisory Committee (MFAC)

or the Energy Research Advisory Board (ERAB).

Through advisory arrangements, DOE gains industry’s expertise and skills, and industry gains

knowledge, contacts, and income. However,

there is no commitment in this type of advisory

relationship that the advice will be used by DOE

or the national laboratories.

Industry as Direct Participant. -To become

major participants in the fusion program, industry executives must understand near-term program objectives and be willing and able to contribute to the achievement of these objectives.

Industry’s direct participation will be particularly

important during the engineering phase of the research program, when information and expertise

must be transferred to industry from the national

laboratories and universities.

As a direct participant, industry can serve a

variety of functions. It can supply off-the-shelf

components, as well as design and manufacture

components made to customer-supplied specifications. One form of direct participation, which

industry sees as most valuable, allows the customer (e.g., DOE, a national laboratory, or eventually an electric utility) to define a project and

to assign responsibility for the task to a company.

Industry can also act as a prime contractor or

project manager; in this case, industry is directly

responsible to a customer for defined aspects of

management, engineering, fabrication, and installation of a product, such as a fusion device or

power reactor.

Industry as Sponsor.—The most extensive

level of industrial involvement will be the sponsorship of private R&D activities. Sponsorship includes the contribution of direct funds, labor, or

both. As a sponsor, industry finances its own research program independently, whereas as a direct participant industry’s activities are largely

financed by the Federal Government. Sponsoring privately funded R&D requires confidence in

the eventual profitability of the technology.

Current Industrial Activities

To date, industrial involvement in fusion research primarily has been advisory, with limited

cases of direct participation. Industry representatives serve on the Energy Research Advisory

Board and the Magnetic Fusion Advisory Committee, both of which advise DOE on the fusion

program. Other industrial participation is facilitated through sub-contracts from national laboratories.

Only one private company, GA Technologies

of San Diego, California, participates significantly

in fusion research. GA Technologies is a private

firm that conducts fusion research under Federal

contract. In this sense, GA has been compared

to a national laboratory in the field of fusion research. The company became involved in fusion

research during the 1950s, when the energy applications of fusion were thought to be closer.

Because GA Technologies (then called General

Atomic Corp.) was able to assemble a high-quality

team of fusion scientists and engineers, the Federal Government has funded the bulk of its fusion research since 1967, when GA lost its primary source of private fusion support. In FY 1987,

GA Technologies received 10 percent of DOE’s

fusion budget.

The fusion program at GA Technologies consists primarily of tokamak confinement research;

GA operates the Doublet II I-D (D III-D) tokamak,

which is the second largest tokamak in the United

States. 28 D II I-D is also the largest U.S. international project. Japan and the United States,

through GA Technologies, have jointly financed

and operated the D II I-D facility since 1979.29

In addition, GA Technologies and Phillips Petroleum Co. invested over $30 million in inventing, fabricating, developing, and operating the

Ohmically Heated Toroidal Experiment (OHTE)

at GA. OHTE is the only major fusion experiment

constructed and operated largely with private

funds. OHTE was completed in 1982 and operated until 1985. In 1985, GA and Phillips requested financial support from DOE for further

development of the concept. However, DOE

would not fund this additional work, initiating a

comparable program at LAN L instead. Without

Z8The Tokamak Fusion Test Reactor (TFTR) at Pri fK@On pbSma

Physics Laboratory is about twice as large as D III-D.

zgFor more information on the international cooperation aSpeCtS

of GA’s D II I-D experiment, see ch. 7, pp. 162-163.
Ch. 6.—Fusion as a Research Program s 149

Photo credit: GA Technologies

OHTE fusion device at GA Technologies, San Diego,

California.

Federal financial support, OHTE was discontinued. In mid-1986, DOE agreed to provide GA

with a grant to operate OHTE, and the experiment was restarted. Recently, DOE decided not

to renew GA’s operating grant for OHTE after FY

1987; it is anticipated that the experiment will be

permanently mothballed.

At this stage in the research program, other private companies have found no compelling reason to sponsor fusion research. Even GA Technologies’ involvement would be severely limited

were it not for extensive Federal funding. Neither are electric utilities currently conducting fusion research. By 1986, the Electric Power Research Institute (EPRI), a utility-funded research

organization, had phased out what had been a

$4 million per year program. According to the

former EPRI fusion manager, EPRI is unwilling to

spend money on fusion because the energy applications are so long-range.30 Individual utilities

 Robert Scott, “Industry and Perspectives on Future

Directions in Fusion Energy Development, ” 

Energy, vol. 5, No. 2, June 1986, p. 138.

are not conducting fusion research either, because of the large investment required and the

difficulty of convincing regulatory agencies to allow research costs to be transferred to ratepayers.

An MFAC panel on industrial participation in

fusion noted that:

. . . fusion commercialization is sufficiently far in

the future and fusion technology sufficiently specialized so that significant cost sharing [between

the Federal Government and the private sector]

should not be expected. The government and its

national laboratories are the immediate customers and should pay the full cost of received products and services. Jl

The position of industry, at least until commercialization is closer, appears to be a subordinate

role supporting the national laboratories and universities.

The role of industry in the U.S. fusion program

is completely different from its role in the Japanese program, where mechanisms for technology transfer from government to industry have

been institutionalized. In Japan, the Japan Atomic

Energy Research Institute (JAERI) and various national laboratories and universities conducting fusion research contract with industry to do all the

design, research, and development that is necessary. As in the United States, the financial contribution of Japanese industry to fusion research

is small. However, its role is critical; according

to one JAERl official, the Japanese Government’s

role is limited to “resolving what type of machine

is needed and designing it, ” and even this task

is “shared” with industry.32 Thus, Toshiba, Hitachi,

and Mitsubishi are intimately involved in fusion

research.

In the United States, in contrast, fusion is primarily a government research program. The national laboratories maintain large engineering

staffs and have strong manufacturing capabilities.

 Fusion Advisory Committee Panel VI Report on 

 Participation in Fusion Energy Development, May 1984,

 5-2 to 5-3,

 official, quoted in H. 

national in Magnetic Fusion Energy: The Industrial

Role. A Strategy for Industry Participation in an International Engineering Test Reactor Project, prepared for the U.S. Department of

Energy, Office of Fusion Energy, August p. 15.
150 “ Starpower: The U.S. and the International Quest for Fusion Energy

DOE has only a limited role at present for involving industry in fusion research; industrial participation is typically ad hoc. Due to the budget cuts

in recent years, the role of industry has been

additionally limited, both because of the few major new projects undertaken and because constricted budgets have made the national laboratories reluctant to subcontract to industry. The

role of industry in the U.S. fusion program is not

institutionalized.

Establishing an Industrial Base

for Fusion

Under current administration policy, the private sector will be responsible for the demonstration and commercialization of fusion technology.

As discussed in chapter 5, it is important to establish an industrial capacity on which the private

sector can base its development efforts. An MFAC

panel on industrial participation in fusion research concluded that:

. . . if a utility is to invest capital to build a fusion

prototype or power plant, it must have confidence in its suppliers. This confidence can be

established only if the suppliers have been qualified through active participation in the fusion

program and have a record of furnishing quality

goods and services.33

Currently, there is controversy over how to prepare the industrial base. In particular, there is extensive disagreement over the timing of industrial participation in the research program prior

to the demonstration and commercialization

stages.

For the research phase of fusion development,

many fusion scientists contend that industry

should be an advisor or low-level direct participant supporting national laboratories and universities. Given the current budget situation and the

nature of the research to be completed before

demonstration and commercialization, these individuals believe that there are not enough opportunities appropriate for industry to develop

and maintain a standing capability in fusion.

Moreover, since the private sector is reluctant to

invest its own funds, proponents of this position

JsMagnetic Fusion Adviso~ Committee panel Vll, op. cit., pp. 2-4.

maintain that it is too early in the program to encourage substantial industrial participation. They

predict that as demonstration and commercialization approach, industry will naturally become

more interested in the applications of fusion technology, hopefully to the point where they are

willing to invest money to explore the technology’s potential. These individuals believe that

limiting industry’s participation in the near-term

will not preclude its eventual role in demonstration or commercialization; they believe premature industrial involvement could be detrimental.

Others argue that it is essential to involve industry in the research effort before the demonstration stage. The proponents of early industrial

involvement stress that technology transfer shouId

occur from the national laboratories and universities to private industry at all stages of the research program, and that such transfer cannot be

effective without active industrial participation.

The willingness of industry to invest in the technology should not be used as a criteria for determining the appropriate degree of involvement,

these people argue, because industry needs information and expertise to accurately assess the

value of the technology.

According to these individuals, early involvement of industry and utilities ensures that the

technology developed will be marketable by vendors and attractive to its eventual users. Technology transfer will take time; if this transfer is not

started until after completion of the research program, fusion’s overall development could be delayed. In addition, proponents of this position cite

a variety of near-term benefits of industrial participation, including increasing support for the fusion program, facilitating spin-offs from fusion to

other technologies, and transferring skills acquired by industries involved in fusion to other

areas of high-technology such as aerospace and

defense.

The impact of various levels of industrial participation in the research program on the successful commercialization of fusion technology cannot be determined now. Since the mechanisms

for transferring responsibility for fusion’s development from the Federal Government to the private sector are not yet known, the impact of early
Ch. 6.—Fusion as a Research Program ● 151

industrial participation on the pace and effective- commercialize fusion technology. If the indusness of this transfer is unclear. However, even trial base is insufficient, it will not only be diffiwithout linking near-term industrial participation cult for industry to construct and operate a demin research to the success of future development, onstration reactor, but the customers (probably

a well-established industrial base must be in place electric utilities) will be reluctant to purchase fubefore the private sector can demonstrate and sion reactors.

SUMMARY AND CONCLUSIONS

Fusion research has provided a number of nearterm benefits such as development of plasma

physics, education of trained researchers, contribution to “spin-off” technologies, and support

of the scientific stature of the United States. However, fusion’s contributions to these areas does

not imply that devoting the same resources to

other fields of study would not produce equivalent benefits. Therefore, while near-term benefits do provide additional justification for conducting research, it is hard to use them to justify one

field of study over another.

Virtually all of the money spent on fusion research in the United States comes from the Federal Government. The fusion program is DOE’s

fifth largest research program, and in recent years

the program has been relatively well-funded compared to DOE’s other energy R&D programs.

Nevertheless, the budget for magnetic fusion

R&D has fallen by about a factor of 2 since 1977

(in constant dollars). These budget decreases

have severely constrained program activities.

Funding limitations have affected the activities

of all three major groups that conduct fusion research: national laboratories, universities and colleges, and private industry. Few new construction projects have been initiated in recent years,

and research in some areas (particularly mirror

fusion) has been curtailed or eliminated. Moreover, many researchers have left fusion. Budget

cuts have also interfered with the attainment of

the program’s near-term goals. In particular, the

ability of the fusion program to attract new researchers to its university programs and to train

them has suffered. Constrained budgets also limit

the participation of industry in fusion research.

In addition, the United States is no longer the undisputed leader in fusion research; the Japanese

and European fusion programs have caught up

with—and may have even surpassed—the U.S.

effort.

OTA has not evaluated whether Federal fusion

research funds are being spent in the most effective and efficient manner. Neither has it evaluated the appropriate priority to be given to fusion research as compared to other research

programs. Comparisons among R&D programs

are difficuIt to make and are typically not made

explicitly during the budgetary process. Therefore, comparative funding levels do not necessarily provide an indication of relative priority.

The appropriate funding level given to fusion research depends on the motivations and goals of

the program. It also depends on where the

money will come from—whether from cutting

other programs or from additional sources of

revenue—and the impacts of these funding choices

reach far beyond the program itself.
Chapter 7

Fusion as an International Program 
r’
Chapter 7

Fusion as an International Program

INTRODUCTION

Many nations of the world have cooperated on

magnetic fusion research for almost 30 years.

Since U.S. magnetic fusion research was declassified in 1958, the major international programs

have engaged in regular information and personnel exchanges, meetings, joint planning efforts,

and jointly conducted experiments. ’

The leaders of the U.S. fusion community continue to support international cooperation, as

does the U.S. Department of Energy (DOE). In

the past, the United States cooperated internationally on a variety of exchanges that have produced useful information without seriously jeopardizing the autonomy of the domestic fusion

program. In recent years, in response to budgetary constraints and the technical and scientific

benefits of cooperation, DOE has begun cooperating more intensively i n fusion, and the major

fusion programs have become more interdependent, For the future, DOE proposes undertaking cooperative projects that will require the

participating fusion programs to become significantly interdependent; indeed, DOE now sees

more intensive international collaboration as a

financial necessity.

Why Cooperation Is Attractive

Without exception, all of the major fusion programs participate in international activities and

look favorably on more intensive future activities. There are several reasons for this widespread

interest. 2

‘Major fusion programs are currently active in the United States,

Japan, the European Community (EC), and the Soviet Union. Primary contributors to the European Community’s fusion program

are the Federal Republic of Germany, France, Italy, and the United

Kingdom, although other member nations are also involved.

ZThe reasons that follow were based i n part on a discussion of

Incentives to collaborate found in: Energy Research Advisory Board,

International Co//~? boration in the U.S. DOE’s Research and Deve/oprrrent Programs, report to the U.S. Department of Energy, prepared by the ERAB International Research and Development Panel,

D(lE/S-0047, December 1985, p, 11,

Fusion Research Is Expensive

The high cost of fusion research is a practical

incentive for nations to cooperate. The next-generation engineering test reactor, for example, is

expected to cost well over $1 billion and possibly several times that much, requiring a substantial increase in U.S. annual fusion budgets if it

were to be built domestically. It is not clear

whether or not the governments of any of the major fusion powers would be willing to construct

such an expensive experiment alone. Given the

expense and considering the similarity in nextstep program goals, the major fusion programs

have agreed in principle that the world does not

need four engineering test reactors of the same

kind. Limited funding can be allocated more efficiently if nations are willing to collaborate on one

major experimental facility.

Fusion Programs Are

at Comparable Levels

The comparable levels of progress among the

major fusion programs make higher levels of cooperation attractive, particularly over the next

decade. While there are differences in emphasis and achievement, the programs have comparable scientific and technical capabilities and

recognize the need for similar next-generation experiments. Cooperative projects are easier to implement in complementary programs because the

benefits can be distributed equitably and because

all participants stand to gain from their partners’

expertise.

Fusion Can Advance More Effectively

International collaboration in fusion research

is attractive because it provides a forum for scientists and engineers to interact. If the major programs can coordinate their activities, the intelIectual resources available to address pressing

issues in fusion research and development (R&D)

can increase dramatically.

155
— — .

156 . Starpower: The U.S. and the International Quest for Fusion Energy

Forms of Cooperation

International cooperative efforts range from

simply exchanging information in international

meetings through the joint construction and operation of experimental devices to complete integration of research efforts.3 Various types of

cooperation entail different levels of program integration, information transfer, and trust. The potential risks and benefits of the programs vary correspondingly.

It is necessary to make a distinction between

the terms “cooperation” and “collaboration. ”

This report will adopt the usage of a recent National Research Council report on cooperation

in fusion research.4 Throughout this OTA assessment, “cooperation” will refer to all activities involving nations, or individuals from different nations, working together. “Collaboration,” a more

intensive type of cooperation, will describe activities involving a substantial degree of program integration, funding commitment, and joint management.

Types of Cooperation and Collaboration

●

●

Information Exchange. Information exchange

is the most common form of international cooperation. Information on achievements and

advances, as well as technical approaches and

experimental data, is exchanged through several channels, including meetings, conferences,

symposia, workshops, and publication in technical journals.

Personnel Exchange. Personnel exchanges–

visits and assignments—also are widely used.

During a typical visit, research scientists tour

one or more of the host program’s facilities for

1 or 2 weeks. Assignments are extended stays

in which the guest participant actually works

on an experiment and contributes to the host

program’s research effort. For the duration of

the assignment, the guest participant is a fullfledged member of the experimental or theo3A discussion of proposals for tutu re cooperation and collaboration now under consideration can be found later in this chapter

under “Prospects for International Cooperation. ”

‘National Research Council, Cooperation and Competition on

the Path to Fusion Energy (Washington, DC: National Academy

Press, 1984), p. 5.

●

●

●

retical team. Assignments are one of the most

effective ways to transfer expertise.

Joint Planning. Joint planning includes activities to identify areas for future cooperative research, to provide a forum for coordinating experimental and theoretical programs on large

experimental devices, and to avoid unnecessary duplication of effort while still ensuring

verification of important experimental or theoretical results.

Joint Research. Through joint research, major facilities are made available for research

projects of other programs. The facility is financed and constructed primarily by the host

program, with other participating programs either providing a percentage of construction

and operation costs or contributing equipment.

In exchange for their contributions, participating programs are granted access to the machine and experimental data. Frequently, contributions of the participants enable an existing

machine to be upgraded; in some cases these

contributions are essential to the construction

of the machine in the first place. Activities involving joint research are becoming increasingly common.

Joint Construction and Operation. Joint construction and operation of major experiments

and facilities are the most intensive forms of

international cooperation; this form of cooperation is referred to as collaboration. Participating programs agree to pool their resources

and construct a commonly owned and operated facility. There is no “host” program in this

case; the facility is operated by a management

team comprised of representatives from each

program.

Plans for future U.S. participation in international fusion activities include collaborative projects in addition to the other levels of cooperation. The largest scale example of a collaborative

project under discussion today would be a jointly

constructed and operated engineering test reactor. The current proposal for this experiment,

called the International Thermonuclear Experimental Reactor (ITER), involves only conceptual

design and supporting R&D for the project. If this

phase of the project is arranged and proves work-
Ch. 7.—Fusion as an International Program . 157

able, more extensive collaboration on construction and operation could be considered.

If successfully negotiated, ITER probably will

be the world’s largest, most expensive, and most

visible cooperative project. Therefore, this chapter primarily focuses on it. The full scope of DOE’s

plans for future cooperative activity includes a

variety of additional, lesser facilities in areas such

as materials research and technology development. DOE plans to investigate more intensive

forms of cooperation–including joint research,

planning, and possibly even joint construction

and operation of facilities—on these other projects as well. The U.S. plans for future cooperation are analyzed in this chapter under “Prospects

for International Cooperation.”

Types of Agreements

Different levels of international agreements

could be used to facilitate cooperation. These

agreements can range from formal treaties down

to informal workshops and publications:

● Treaty. A treaty between governments is the

most binding and formal agreement that can

be established. Ratification signifies commitment to the substance of the agreement;

obligations incurred under a treaty can be

abrogated, but such action is not taken lightly

or often. However, a treaty is the most difficult type of agreement to implement. There

is a greater risk of negotiations breaking

down during the development of a treaty,

and more issues must be resolved in order

for a treaty to be ratified. Moreover, the ratification process for a treaty is time-consuming;

a treaty may be obsolete by the time it is finally ratified. In the United States, a treaty

must be signed by the President and ratified

by a two-thirds majority of the Senate.

● Heads-of-State Agreement. A heads-of-state

agreement is less formal than a treaty but is

considered binding by most governments.

Such an agreement carries the full weight of

the government in power, and abrogation

by a signatory head of state would bean unusual, though not impossible, act. When the

subject of the agreement has a strong base

of support among many different groups, the

●

●

D

risk that the signing head of state, or a succeeding one, would disavow the agreement

is small.

Ministerial-level Agreement. A ministerial

agreement is arranged between ministries of

the participating governments, and it is less

formal than either a treaty or a heads-of-state

agreement. It requires less review and approval than the more formal agreements and

is affected more directly by changes in budgetary constraints and political objectives.

However, it still carries the full weight of the

government. In the United States, ministerialIevel agreements in fusion research are negotiated with participation of the Departments of Energy and State.

Informal Arrangement. An informal arrangement can be undertaken between governments, laboratories, and individuals. It can

provide an excellent means of transferring

information among scientists, but it does not

provide a basis for programmatic or international planning. This arrangement is typically

instituted on an ad hoc basis, in response to

particular needs and objectives of the participants.

ifferent types of agreements are appropriate

for the various forms of cooperation that occur

in fusion and in other areas (see table 7-1).

Most cooperative efforts occur u rider a general

arrangement called an umbrella agreement. A n

Table 7-1.—Comparison of Type of Cooperation

and Level of Agreement

Type of cooperation Level of agreement

Information exchange . . . . . . . Informal Arrangement

Ministerial Agreement

Heads-of-State Agreement

Personnel exchange . . . . . . . . . Informal arrangement

Ministerial Agreement

Heads-of-State Agreement

Joint planning . . . . . . . . . . . . . Ministerial Agreement

Heads-of-State Agreement

Joint research . . . . . . . . . . . . . . Ministerial Agreement

Heads-of-State Agreement

Joint construction and

operation . . . . . . . . . . . . . . . . Ministerial Agreement

Heads-of-State Agreement

Treaty

SOURCE Office of Technology Assessment, 1987
158 ● Starpower: The U.S. and the International Quest for Fusion Energy

umbrella agreement usually is established as part

of a ministerial agreement before any specific cooperative agreement is instituted. It defines the

principles of cooperation and provides a framework for developing future cooperative agreements. It is undertaken when governments are

interested in cooperation and want to formalize

the intent to cooperate. An umbrella agreement

typically states that the participating governments

support cooperation and are ready to begin negotiating specific cooperative projects.

ogy, sets up joint planning and negotiation efforts,

and provides a forum for exploring the potential

of future cooperation on medium- and long-term

projects. An umbrella agreement is not a final

agreement. It is not intended to address the substantive issues involved in decisions to undertake

specific cooperative projects. It is a useful device,

however, for defining areas of potential cooperation and for creating a framework for negotiating future agreements.

Frequently, an umbrella agreement authorizes

transfer of preliminary information and technolMAJOR INTERNATIONAL AGREEMENTS

Under current arrangements, the United States

participates in cooperative fusion activities at all

levels except that of joint construction and operation. To date, only one international fusion project has been collaborative in this sense: the joint

European Torus project of the European Community (EC). Table 7-2 summarizes the principal

existing international fusion arrangements; the

organizations and agreements mentioned in the

table are described below.

Multilateral Activities

International Atomic Energy Agency

The International Atomic Energy Agency (IAEA)

has been one of the most important facilitators

of fusion cooperation. The IAEA is an independent intergovernmental organization within the

United Nations system, and its mission is to promote and ensure the peaceful use of atomic

Table 7-2.—Principal International Fusion Activities

Type of cooperation Representative project Agreement

Information exchange. . . . . Large Tokamak Agreement

Nuclear Fusion journal

Conferences

Personnel exchange . . . . . . Large Tokamak Agreement

50 transfers each way

Six transfers each way

To be determined

Joint research . . . . . . . . . . . ASDEX Upgrade

Large Coil Task

Doublet III-D Upgrade

Tore Supra

Joint planning . . . . . . . . . . . INTOR

Large Tokamak Agreement

Joint Institute for Fusion Theory

To be determined

Joint construction and

operation . . . . . . . . . . . . . . Joint European Torus

SOURCE: Office of Technology Assessment, 1987.

IEA

IAEA

IAEA

IEA

U.S.-Japan Bilateral

U.S.-USSR Bilateral

U.S.-EC Bilateral

IEA

IEA

U.S.-Japan Bilateral

U.S.-EC Bilateral

IAEA

IEA

U.S.-Japan Bilateral

U.S.-EC Bilateral

European Community
Ch. 7.—Fusion as an International Program “ 159

energy. The headquarters of the IAEA are located

in Vienna, Austria. All countries currently doing

fusion research are members of the IAEA. It has

facilitated two different types of cooperative activity: information exchanges and joint planning

efforts.

Major informational activities conducted by the

IAEA in the area of fusion research include hosting biennial meetings and arranging topical meetings and workshops on areas of special interest

or concern. In addition, the IAEA publishes a

technical journal, Nuclear Fusion, in which fusion researchers can share their findings.

The IAEA also facilitates a joint planning activity, called the International Tokamak Reactor (l NTOR) design study. INTOR began in 1978, and

it involves the European Community, Japan, the

Soviet Union, and the United States. The goal of

INTOR is to define concepts and designs for a

conceivable next-generation fusion experiment.

It is a forum where Western fusion scientists have

regular contact with their Soviet counterparts. National teams work on parallel tasks and meet two

or three times a year for several weeks to compare results and plan future work. Most analysts

agree that INTOR discussions have successfully

identified critical issues in both physics and technology.

International Energy Agency

The International Energy Agency (IEA) was created by 21 Western oil-importing nations in 1974

in response to the OPEC oil embargo. IEA’s main

task is to plan for crisis response to future oil embargoes. In addition, the IEA also promotes international cooperation in research and development of energy technologies that have the

potential to decrease the West’s dependence on

oil imports, The European Community, Japan,

and the United States participate in IEA’s cooperative projects. Magnetic fusion research is one

of many areas IEA promotes, largely by facilitating joint research efforts. The IEA is headquartered in Paris, France.

In 1977, the Large Coil Task (LCT) was organized u rider the auspices of the I EA. As part of

the LCT, the U.S. fusion program constructed the

International Fusion Superconducting Magnet

Test Facility at Oak Ridge National Laboratory in

Tennessee at a cost of about $40 million. This facility is designed to test superconducting magnet

coils. s It holds six large coils, one each constructed by the European Atomic Energy Community, the Japan Atomic Energy Research Institute, and the Swiss Institute for Nuclear Research

and three constructed by U.S. manufacturers. 6

Each coil cost between $12 million and $15 million to construct. international involvement in the

LCT has distributed the costs of the project among

several nations, and it has also enabled different

types of coils to be tested in a common facility,

allowing direct comparison. Moreover, the LCT

is the major instance in the fusion area that involved industry in international cooperation.

Several other cooperative projects also occur

under IEA auspices. The European Community

and the United States participate in joint planning on next-generation stellarator experiments

to coordinate their research efforts. It appears that

Japan will soon be joining this project. Through

the IEA, the United States and the European Community are also conducting joint research on the

Axisymmetric Divertor Experiment (ASDEX) and

its upgrade (ASDEX-U). These facilities are located

at the Institute for Plasma Physics at Garching,

Federal Republic of Germany, and U.S. participation in this research has made it unnecessary

for the United States to construct similar facilities.

The IEA provides no funding for any of these

projects, only an umbrella framework and minor

secretariat functions.

The most recent IEA agreement, signed in January 1986, provides for cooperation among the

three large operational tokamak experiments (jT60 in Japan, the joint European Torus (JET) in the

European Community, and the Tokamak Fusion

Test Reactor (TFTR) in the United States). Under

this agreement, the three programs conduct personnel and information exchanges for tokamak

experiments. An executive committee, consisting of two members from each fusion program,

5For a discussion of the role of superconducting magnets in a fLJ -

sion reactor, see the section of ch. 4 titled “The Magnets” under

“Fusion Power Core Systems. ”

W .S. Department of Energy, Office of Energy Research, ,14agnefrc

Fusion Energy Research: A Summary of Accomp/ishmerrts, DOE/ER0297, December 1986, p. 19.
160 . Starpower: The U.S. and the International Quest for Fusion Energy

Photo credit: Oak Ridge National Laboratory

The International Fusion Superconducting Magnet Test Facility at Oak Ridge National Laboratory, containing the six

superconducting magnets.

will meet at least once a year to coordinate research. The agreement is in effect from 1986 to

1991. This agreement has the potential to evolve

into joint planning and program coordination.

Joint European Torus

The joint European Torus is Europe’s most important experimental fusion facility and the world’s

largest tokamak. JET is a joint undertaking of the

member nations of the European Community; it

has been designed, constructed, and operated

by the EC. The JET Working Group was created

to explore the project in 1971; the device was

approved by the EC Council of Ministers in 1978,

following a political wrangle of 21/2 years over

project location.

The JET experiment is located adjacent to the

Culham Laboratory, in Abingdon, United Kingdom. The land on which JET is constructed is temporarily leased from the United Kingdom; at the

completion of the project the land will be returned.

Construction of JET began in 1977, and the facility began operating in 1983; current plans call

for JET to operate until about 1992. 7

 of design phase and the political negotiations concerning JET, see Denis A European Experiment:

 Launching of Project (Bristol, U. K.: Adam Ltd.,

1981 ).
Ch. 7.—Fusion as an International Program ● 161

Photo credit: JET Joint Undertaking

The Joint European Torus, located in Abingdon,

United Kingdom.

Legally, JET is an independent international entity; it is not a national project. The JET administrative structure is multinational. The project is

managed by a project director on site, but all important strategic decisions must be presented to

and approved by the JET Council, which is comprised of two members from each participating

nation, one of which is a scientist. When the

project is completed, the administrative structure

will be dismantled.

JET is staffed by two distinct and roughly equalized groups: the multinational staff supported by

the EC and a local staff supported by the United

Kingdom Atomic Energy Agency. Provisions have

been made for staff to return to their national fusion programs after completion of their appointments at JET.

The EC pays 80 percent of the costs of JET

through the contributions of member nations. in

addition to their contributions through the EC,

the national programs also contribute directly to

the project. Direct national contributions represent 10 percent of the costs. The final 10 percent

is a site premium paid by the United Kingdom.

This premium offsets the financial benefits that

the host country receives from the project. In the

last 5-year budget plan, approved in 1985, funding for the overall EC fusion program for 1985-

89 was set at 690 million European Currency

Units (worth at that time about $766 million). Of

this amount, roughly half will go to JET.

The JET model has been effective and efficient.

Through cooperating on the project, national programs have saved money, have had access to a

world-class experiment, and have advanced the

state of European scientific research.

Bilateral Activities

United States-Japan Bilateral Agreement

In 1979, a ministerial-level agreement was signed

committing the United States and Japan to cooperate on general energy research and, more

specifically, to develop commercial fusion power

for the 21st century. Within the framework of this

umbrella agreement, the United States and Japan

have negotiated several specific cooperative

agreements. The U.S.-Japan cooperation is the

most extensive international cooperation in fusion research in which the United States participates. Information and personnel exchanges,

joint research activities, and joint planning activities all occur within the context of the umbrella

agreement.

About 50 formal personnel exchanges occur

each way annually between the United States and

Japan. 8 There are also a few (usually under 10)

personnel exchanges arranged yearly on an ad

hoc basis; these informal exchanges enable the

partners to accommodate unique program needs.

‘Michael Roberts, rector I Programs, U 

 Energy, Fusion Energy, letter to the 

 Technology Aug. 1986.
162 ● Starpower: The U.S. and the International Quest for Fusion Energy

Photo credit: GA Technologies, Inc.

D II I-D fusion device at GA Technologies, San Diego, California, showing neutral beam injection systems.

Under the umbrella agreement, a specific agreement to conduct a major joint research project

was also signed in 1979. Through this agreement,

Japanese involvement in the upgrade of the U.S.

Doublet Ill (D Ill) tokamak was formalized.9 The

Japanese and the Americans shared machine time

on the experiment equally, and both have had

access to all data generated in the experiments

run on the machine.

“U.S. of Energy, Magnetic fusion Energy Research,

op. cit., p. 20.

The United States hosts the Doublet project,

which is located at GA Technologies’ laboratory

in California. Since 1979 the project has had joint

funding and a joint management team. Between

1979 and 1984, the United States contributed

$104 million and the Japanese contributed $62

million to finance an upgrade in the D Ill facility

(after the upgrade the name was changed to D IIID). In 1983, the agreement was extended until

1988, and additional upgrades were undertaken

for which the United States is contributing $37.8

million and Japan $8.5 million. Currently, discus-
Ch. 7.—Fusion as an International Program ● 163

sions are underway to extend cooperation until

1992.

10

The Doublet cooperation has provided both

parties with access to a state-of-the-art tokamak

for much less than the cost of independently constructing and operating the experiment. In fact,

it is unlikely that the D Ill upgrades would have

been possible without Japanese funding contributions. In addition, Japanese and U.S. scientists

both have made valuable technical contributions

to the experiment that have improved the scientific quality of the project.

Within the context of the U.S.-Japan umbrella

agreement, the countries also have undertaken

joint planning activities. The United States and

Japan have created a joint Institute for Fusion

Theory (JlFT) and designated two theory centers,

one at the University of Texas at Austin and the

other at Hiroshima University in Hiroshima, Japan.

Each fusion center has continued to operate independently, and a coordinating committee has

been created to oversee and guide cooperative

activities.

United States-U.S.S.R.

Bilateral Agreement

The Soviet Union has cooperated extensively

with the United States and has made substantial

contributions to the U.S. fusion program (see the

history of tokamak development in ch. 3). The

United States and the Soviet Union have had a

formal agreement to cooperate in fusion research

since 1958. In 1973, this agreement was strengthened, under the Nixon-Brezhnev Accord, to extend and broaden cooperation in fusion research.

Most of the detailed information that the U.S. fusion program has about the Soviet program comes

from the U.S.-Soviet exchange activities.11

Under the terms of the Nixon-Brezhnev Accord, 12 personnel exchanges occur between the

United States and the Soviet Union annually, six

——. .— 10Test;mony of Dr. David Oversket, Senior Vice President at GA

Technologies, Inc., before the House Science, Space, and Technology Committee, Energy Research and Production Subcommittee on the Fiscal Year 1988 Magnetic Fusion Energy Budget, Feb.

24, 1987, p. 4.

11 u .s, Depa~rnent of Energy, Office of Fusion Energy, ~Va/Uation of Benefits of Cooperation on Magnetic Fusion Energy Between

the United States and the Soviet Union for the period 1983 to 1985,

November 1985.

in each direction. These exchanges are limited

by the United States to fusion science issues, such

as experiments and theory, with no regular interaction on technology development .12 Most of

the personnel exchanges are visits; some are assignments, however, which have given Soviet scientists an opportunity to work with U.S. scientists on research projects, and vice versa,

The U.S.-U.S.S.R. bilateral agreement is vulnerable to the political situation between the two

countries. For example, no exchanges occurred

during 1980 or 1981, the years following the Soviet invasion of Afghanistan. However, since the

1985 U.S.-U.S.S.R. summit meeting in Geneva,

bilateral activity between the nations has progressed

to a point where collaboration with the Soviet

Union on the conceptual design and supporting

R&D of a major fusion experiment is being considered. 13

United States= European Community

Bilateral Agreement

The United States and the European Community have cooperated extensively for more than

30 years without a formal bilateral agreement.

Until recently, most cooperation involving the EC

and its member states was conducted indirectly

through the I EA. While this cooperation was rewarding, many tasks were not easy to arrange

under the existing arrangements.

A ministerial agreement was signed between

the United States and the EC in December 1986.

Because the agreement was signed so recently,

details for all of the activities that will occur within

its framework have not yet been formalized. Arrangements have been made for joint research

at the JET facility in the United Kingdom and at

the Tore Supra facility in France. The agreement

will provide an annual forum for management

discussions about bilateral cooperation issues and

will establish a legal basis that can simplify the

exchange of hardware and the initiation of some

cooperative endeavors. It also will increase the

mobility of European scientists; within the EC, a

formal agreement helps facilitate personnel exchanges.

I Zlbid., app. A.

1 IThe Geneva summit meeting and the SU bseq uent proposal for

a major fusion collaboration involving the Soviet Union are discussed on p. 184.
.

164 . Starpower: The U.S. and the International Quest for Fusion Energy

EVALUATION OF COLLABORATION

Benefits and Risks

Knowledge Sharing

All forms of international cooperation involve

information transfer. Throughout the history of

fusion research, access to information–including

technical know-how, experimental data, and new

theoretical ideas—has enabled fusion scientists

to learn from each other. Innovative ideas and

a wider variety of approaches to projects are

more likely to arise in an international versus a

purely domestic program .14 Researchers can compare their experimental results with those of other

programs, making it possible to verify results,

identify anomalous data, and distinguish experimental results based on fundamental characteristics from results based on special features or

flaws in a particular experimental device. Thus,

scientific progress can occur more rapidly through

cooperation.

On the other hand, some observers feel that

extensive knowledge sharing between national

fusion programs should be discouraged in the interests of national security and national competitiveness. These individuals believe that the advantages of information transfer, in terms of

improved scientific research, do not outweigh the

disadvantages of participating in extensive cooperative projects.

Cost Sharing

One advantage of international cooperation is

that it potentially can save significant amounts of

money. Information and personnel exchanges

enable independent programs to learn, at low

cost, about the research activities of other programs. joint planning activities enable fusion programs to coordinate activities to avoid duplication of effort and to conduct mutually beneficial

research. Most dramatically, joint research and

joint construction and operation of projects distribute the costs of major experimental facilities,

while still providing the experimental results to

all participants.

lqsee U.S. Departrnerrt ot Energy, Office of Energy Research, /fJternational Program Activities in Magnetic Fusion Energy, DOE/ER0258, March 1986, p. 5; or National Research Council, Cooperation and Competition, op. cit., p. 19.

The full extent of the cost savings is unclear,

however. As the National Research Council report pointed out, because cooperation requires

extensive negotiation and more formal management structures, the total administrative costs of

constructing and operating a cooperative project

are higher than if the same project were constructed independently.15 Moreover, there are

additional costs if the facility is not sited in the

United States, such as lost domestic contracts,

employment, and support facilities.16 Although

these added costs temper the financial benefits

of international cooperation, it is expected that

the contribution of any one partner will be less

than the cost of that partner proceeding independently with an identical project.

Risk Sharing

International cooperation on major

mental facilities can mitigate the risk of

experi -

project

failure by spreading the financial and programmatic costs over all participants. Constructing and

operating large experimental facilities is expensive; the cost of failure, both monetarily and on

a program’s morale and future plans, can be high.

Through sharing knowledge between major fusion programs, there is a greater probability of

scientific or technical success, In addition, the formal agreements required to negotiate an international project and the political implications of

abandoning such an undertaking may serve to

stabilize national commitments to the project.

On the other hand, some scientists feel that the

absence of competition and duplication among

I JNationa[ Research Counci 1, Cooperation c?nd competition, op.

cit., p. 31. Actual statistics are difficult to collect; however, one su rvey of technical personnel involved in the I NTOR workshop indicated that constructing INTOR as an international project would

increase total costs by about 70 percent, staffing requirements by

15 percent, and require 2 years longer to complete. It is not clear

that these projections are generally applicable; cooperative construction of JET probably did not inflate costs this much. However,

no matter to what degree, collaboration will tend to increase construction times and project costs.

IGTesti mony of Dr. Walter A. McDougall, Associate ?rOfeSSOr of

History at the University of California–Berkeley, Science Po/icy

Study Vo/ume 7: /nternationa/ Cooperation in Science, Hearing before the Task Force on Science Policy of the Committee on Science and Technology, House of Representatives, 99th Cong., 1st

sess., June 18-20 and 27, 1985, p. 70.
Ch. 7.—Fusion as an International Program ● 165

experimental facilities may increase technical risk

and that extensive cooperation may increase the

risk of abandonment before project completion.

Some members of the fusion community point

out that coordinating research to the point of

jointIy constructing a single international facility,

as opposed to comparable national facilities,

would eliminate the potential for validating experimental results through comparisons between

different machines of similar size and purpose.

With more than one machine, a number of different scientific and technical approaches could be

explored, and experimental results among machines could be compared. In addition, some feel

that the absence of competition among facilities

will lead to more conservatism in design and

operation, which can limit progress. Finally, all

participants must fulfill their financial and personnel obligations if the project is to succeed, especially with larger, more complex projects that extend over several years. The entire project can

be jeopardized if even one nation abrogates the

agreement, and cancellation can have implications

far broader than just one abandoned project.17

Diplomatic and Political Implications

A large cooperative experiment will clearly

have significant diplomatic and political implications. Many proponents of international cooperation believe the diplomatic and political consequences can be positive. The commitment to

cooperate on an experimental fusion device is

not trivial; a commitment represents confidence

in the reliability of the other participants and faith

that they can work together to the benefit of all

involved. Through the negotiating process, differences between partners can be reconciled and a

commitment to a common goal can be affirmed.

In addition, the diplomatic value of a decision

to cooperate could be used to further U.S. objectives and improve U.S. relations in areas otherwise unrelated to fusion, For example, an agreement to cooperate on magnetic fusion could be

reached as part of a larger non-technical diplomatic initiative. Some observers argue that such

diplomatic benefits have been particularly valuI TNationa] Research COU ncil, Cooperation and Competition, op.

cit., p. 23.

able in the case of U.S.-Soviet cooperation, and

that more intensive cooperation with the Soviets

should be pursued.

Some people consider these non-technical diplomatic benefits a positive feature of large-scale

cooperative projects. Others, however, fear that

the diplomatic implications of collaboration could

result in the subordination of technical objectives

to non-technical goals, which would be undesirable. Moreover, some observers fear that international projects should be viewed cautiously because broken cooperative agreements could

complicate international relations. If a nation

abandoned its commitment in the course of a cooperative undertaking, there could be important

political consequences. The fear of these consequences might even cause reluctance to terminate a technically undesirable project.

Domestic Implications

In addition to its technical benefits, many

proponents of cooperation support it as a method

of preserving the U.S. fusion program. These individuals are concerned, at least in part, that current budgets are insufficient to maintain a viable

domestic fusion effort. At current funding levels

and as currently structured, the U.S. fusion program cannot construct and operate essential experimental facilities on its own without dramatic

curtailment of other necessary aspects of the fusion effort. Collaboration proponents therefore

see intensive international cooperation as critical for a challenging, growing U.S. research program. This point is made in the National Research

Council report:

For the United States at this time, large-scale

international collaboration is preferable to a

mainly domestic program which wouId have to

command substantial additional resources for the

competitive pursuit of fusion energy development

or run the risk of forfeiture of equality with other

world programs.18

Increased international cooperation in fusion

energy research can also stabilize the commitment of the U..S Government to the magnetic fusion program.19 Moreover, international projects

‘

8

1 bid., p. 11.

‘g Ibid., p. 22.
166 . Starpower: The U.S. and the International Quest for Fusion Energy

often have more visibility than domestic undertakings and therefore can better mobilize public

support.

However, incentives for future collaboration on

big fusion projects must be traded off against a

variety of other domestic concerns. Some members of the fusion community, for example, worry

that the United States might link the continued

viability of its fusion program to international

activities that it cannot adequately influence. *0

Others are concerned that U.S. policy makers

might sacrifice the Nation’s domestic fusion program in order to promote international cooperation,21 particularly if domestic budgets were not

increased sufficiently to cover the additional cost

of an expensive cooperative project. In addition,

some individuals are concerned that undesirable

changes in the direction of fusion research might

be made to facilitate increased cooperation. Finally, there is concern that the participation of

domestic universities and industry in fusion research could be limited if the program emphasizes international cooperation.

Obstacles

22

A number of potential obstacles must be addressed through negotiation before the United

States can participate in large-scale cooperative

projects in fusion research.

Technology Transfer

Transferring high technology to our partners

could be the most serious political obstacle to

more intensive international cooperation. Many

critics worry that militarily significant technology

could be transferred, either directly or indirectly,

to the Soviet Union through fusion cooperation,

especially through joint construction and oper-

— ——— ,?ol bld ,

21 Ibid., p. 23.

zzThe information in this section is based on a workshop on issues in International Cooperation held by the Office of Technology Assessment, Washington, DC, on Oct. 14, 1986 (list of panelists

presented in front of this report); on reports done under contract

to OTA by specialists in Japan, Europe, and the Soviet Union; on

discussions and interviews conducted with members of the fusion

community; and on the National Research Counci I report Cooperation and Competition, op. cit.

ation projects. Some analysts are also concerned

that cooperation in fusion could jeopardize U.S.

competitiveness in international markets.

National Security .–Some of the technologies

developed for use in fusion experiments–e.g.,

high-power neutral beams, high-power microwave technology, and plasma diagnostics—can,

with varying degrees of modification, have military applications. Various individuals and government agencies contend that the Soviet Union will

be able to utilize technology transferred through

more extensive fusion cooperation for military applications. According to Richard Perle, former Assistant Secretary of Defense for International

Security Policy, “Soviet officials and agents have

successfully exploited the openness of the U.S.

and European scientific communities to gather

militarily useful technical information.”23 Opponents of extensive cooperation with the Soviets

contend that it wouId be difficult, if not impossible, to control the transfer of militarily sensitive

technology in an experimental facility such as

ITER. In particular, opponents contend that longterm association with Western scientists will provide disproportionate benefits to the Soviets. Opponents say that through the ITER project, Soviet

scientists will be able to acquire Western knowhow, technology, and experience in leading-edge

technologies.

Supporters of cooperation do not claim that

military applications of fusion-related technologies are irrelevant, but they believe that many

of the concerns raised by opponents are overstated. When examined in detail, proponents argue, most of the objections disappear, and those

that remain can be addressed on a case-by-case

basis. As the Director of the Office of Energy Research at DOE has stated:

It is my opinion . . . that a device of the sort we

are talking about could be built and that the necessary computer activities associated with it could

be carried out in a manner that did not involve

any violation to COCOM regulations.24

zjRichard perle, Assistant Secretary of Defense for I nternatlona I

Security Policy, “Technology Security, National Security, and U.S.

Competitiveness, ” /ssues in Science and Technology, fall 1986, vol.

[II, No. 1, p. 112.

~aTestlmony of AIvin W. Trivelpiece, Director Of the office of

Energy Research, U.S. Department of Energy, Fisc~?/ Year /987’ De-
Ch. 7.—Fusion as an International Program ● 167

Proponents point out that, generally, fusion

technologies are not directly applicable to military needs; those technologies that do have defense applications must undergo substantial modification and redesign before reaching military

significance. For example, although many of the

technologies currently being investigated in the

Strategic Defense Initiative were first developed

for or used by the magnetic or inertial fusion programs, U.S. scientists are nevertheless spending

billions of dollars to apply these technologies to

weapons systems. Applying fusion technologies

to military uses may require as much indigenous

technical capability as developing the technologies in the first place.

Furthermore, supporters of U.S.-Soviet fusion

collaboration argue that those technologies posing true risks can be identified through careful

review procedures and that problems can be handled on a case-by-case basis. If, for example, a

particular component poses a significant technology transfer risk, the Soviets couId be asked to

provide it, its use could be restricted, or the experiment could be redesigned to eliminate it.

Proponents of increased cooperation insist that

there are significant benefits to the United States

from collaborating with the Soviet Union that

must be weighed against the risks. Magnetic fusion research is not classified; information about

experiments, techniques, and methodologies are

available in international publications. Moreover,

as the Associate Director of Confinement at Oak

Ridge National Laboratory noted:

Everything in the world is not done here. In

many areas we are not ahead . . . We got the fact

that you could make a gyrotron [a high-power

microwave generator] from the Russians. All sorts

of things came out of the Russian program .25

—.— .——

partment of Energy Authorization: Magnetic Fusion Energy, Hearings before the Subcommittee on Energy Research and Production,

Committee on Science and Technology, House of Representatives,

99th Cong., 2d sess., Feb. 25-26, 1986, p. 24.

COCOM IS the acronym of the Coordinating Committee, an informal, voluntary, cooperative alliance through which the United

States and its allies seek to control the export of strategic goods

and technology to the Eastern bloc, It is an intergovernmental com -

m ittee, and 15 nations participate i n it—the NATO countries (except for Iceland and Spain) and Japan. Members of COCOM have

agreed to restrict export of certain specified items to Communist

cou ntrles for strategic reasons.

25Mark Crawford, “Soviet-U.S. Fusion Pact Divides Administration, ” Science, May 23, 1986, p. 926, quoting John Shefflelci, Associate Director of Conti nement at Oak Ridge National Laboratory.

72-678 () - 87 _ 5

Over the years, the Soviet Union has made valuable contributions to fusion research, and its

participation in a major project would improve

the quality of the undertaking.

Undoubtedly, measures taken to resolve technology transfer concerns will constrain the free

flow of information and technology between the

partners in collaboration. Such constraints may

pose an obstacle to collaboration in their own

right: it is possible that after compromises have

been made to satisfy technology transfer concerns, the proposed collaborative project might

not satisfy the needs of the parties in the activity, including the U.S. fusion community. If, for

example, it was decided that the use of old technology would avoid the risk of transferring stateof-the-art technology, the overall capabilities of

the device could be reduced, and as a result the

project could become less attractive.

The national security debate is not easily resolved, and it involves underlying motivations

and assumptions concerning the U.S.-Soviet relationship that go far beyond the details of any specific technical exchange. Given the depth of the

debate within the U.S. Government, it appears

that the United States will not be able to participate in a major joint undertaking with the Soviet

Union until these issues are settled. Many observers contend that resolving the national security questions ultimately will require a presidential decision.

U.S. Competitiveness.–Many analysts are concerned about the competitiveness of American

industry in international markets, and some are

hesitant, in particular, about the long-term implications of intensive cooperation with the Japanese and the Europeans i n fusion.26 At present,

U.S. industry is only minimally involved in the

fusion program. If no provisions are made to

directly involve U.S. industry in future collaborative projects such as ITER, some observers fear

that U.S. industry could fall farther behind Japanese industry—particularly since Japanese industry is more directly involved in fusion research.27

jGThe General Accounting Office documents th IS concern in Its

report The Impact ot International Cooperation in DOE’s Magnetic

Confinement Fusion Program, report to the Honorable Fortney H.

Stark, Jr., House of Representatives, GAO/RCED-84-74, February

1984, pp. 13-14.

jTFor a more detai led d Iscussion of i nd ustria I participation I n the

U.S. fusion program, see the section in ch. 6 titled “Prl\ate industry. ”
168 ● Starpower: The U.S. and the International Quest for Fusion Energy

DOE does not consider U.S. competitiveness

issues to pose a serious obstacle to increased cooperation in fusion. As DOE points out, magnetic

fusion is currently in a pre-competitive stage. Because there are few commercial applications of

the technology, there are no substantial risks from

sharing the technology internationally, According to DOE, there appears to be little risk that the

United States would sacrifice its future competitive position through near-term cooperative endeavors.

Technical Differences

Successful cooperation on a major device like

ITER requires that the partners agree on a common set of goals and objectives, that their fusion

programs beat comparable levels, and that they

be moving in compatible directions. Differences

between the long-term objectives of the partners’

fusion programs or research plans must be accommodated or resolved.

At present, all the major world fusion programs

agree on the need for an experiment such as ITER

and welcome it as an opportunity for more intensive cooperation. However, given the differences in detailed technical objectives among the

programs, designing an experiment that satisfies

each program’s goals simultaneously will involve

a great deal of negotiation and compromise.

Project Location

Siting major projects, whether domestically or

internationally, is traditionally time-consuming

and politically sensitive. According to the National Research Council, selecting a project site

is a “frequent sticking point in large international

projects.” 28 Intense competition for the site of a

major international fusion project can be expected,

since such a facility will be beneficial to local institutions, may provide some advantage to local

industry, and will carry a great deal of prestige.

Most analysts believe it is unlikely that the facility will be located in either the United States

or the Soviet Union. It is not expected that either nation would participate if the project were

28National Research council, cOOpHdtbJ dfld cO~pe~ifiO~, op.

cit., p. 57.

located within the other’s borders. In addition,

with both the Western Europeans and the Japanese sensitive about superpower dominance,

they too might be reluctant to site the project in

either the United States or the Soviet Union.

Even after the competition is narrowed down

to one nation or region, internal competition for

the site will be intense. In the case of the JET

project, for example, the siting negotiations took

over 21/2 years to resolve and almost caused the

abandonment of the project. 29 The siting decision for ITER probably will be even more difficult, since it will be a larger facility and more nations will be involved. Collaboration on ITER

requires that the project have value to all participants, including those that do not host it.

U.S. Commitment

Another difficulty for U.S. participation in a major international joint undertaking is the degree

of commitment by the U.S. Government to the

fusion program. The U.S. fusion program has

faced decreasing budgets, in real terms, for 9 of

the last 10 years, and, given this recent history,

international partners could reasonably question

U.S. commitment to the development of fusion

energy, Moreover, many nations already believe

that cooperating with the United States is risky.

A recent Energy Research Advisory Board panel

on DOE’s international research and development activities concluded:

. . . the Department [of Energy] has a poor reputation abroad for long-term commitment to international collaborative programs. This poor reputation will make it extremely difficult for DOE to

attract foreign countries into significant new partnerships . . . the responsibility lies with DOE to

improve its own image abroad.30

The United States needs to establish a strong and

stable commitment to its domestic fusion program as well as to international projects in order

to win the confidence of potential partners.

zgDenis Wlllson, A European Experiment: The Launching of the

JET Project, op. cit.

JoEnergy Research Advisory Board, International Collaboration

in the U.S. Department of Energy’s Research and Development Programs, op. cit., p. 2.
Ch. 7.—Fusion as an International Program . 169

Equitable Allocation of Benefits

Negotiating an agreement in which the benefits of the project are distributed equitably in relation to the investment of the participants will

be complex. Among the benefits are the distribution of available staff positions, the amount of

design and equipment fabrication work to be

done by contractors, and the access or rights to

information and technical know-how generated

by the project. Benefits associated with hosting

the site of the experiment also must be accounted

for, a task that has frequently resulted in requiring the host to contribute more to the project’s

costs. I n the JET project, for example, the United

Kingdom contributes 10 percent of project costs

as a site premium, over and above its contribution as a participant.

Administration

For cooperation to be successful, it will be necessary to resolve a variety of administrative issues

faced in all cooperative programs.

Different Institutional Frameworks.–Each national agency involved in negotiations operates

under different ruIes and procedures. In addition,

the negotiating agencies generally have varying

degrees of autonomy, flexibility, and decisionmaking power.

Decentralization of the U.S. Government.—

The decentralized character of the U.S. Government poses a challenge to developing major international agreements. Each executive branch

agency has different concerns, making it difficult

for the U.S. Government to reach the consensus

needed to “speak with one voice. ” Therefore,

negotiators will have to ensure either that there

is widespread commitment to the project within

the U.S. Government or that the project has support at levels of government high enough to assure such a commitment.

Different Budget Cycles.–Agreements will

have to reconcile differences in national budgetsetting procedures in order to finance a major

cooperative undertaking. The European Community, for example, has a multi-year budget cycle,

whereas both the United States and Japan have

annual budget cycles. Even these annual budget

processes are quite different. Whereas the Japanese budget process is very incremental, with major changes in program funding levels being unusual, in the United States the budget cycle is less

stable and less predictable. Funding choices are

reevaluated annually in the United States, and

changes in priorities are common. Thus, there is

some concern that the United States might make

a commitment to begin a long-term project and

then change its mind.

It has been suggested that the United States

adopt a multi-year budget cycle or take major international projects “off-budget.” While such actions certainly would reduce the budgetary obstacles to cooperation, the chance of such a

change is slim, because the ramifications of such

a decision wouId extend far beyond any particular project.

Different Currencies and Economic Systems.– It

is generally considered easier if international project management minimizes currency transfers between nations. Different budget cycles, fluctuating exchange rates, and different economic systems

—particularly with regard to the Soviet Union—

make limiting the exchange of currency an attractive goal. Therefore, having participants contribute components and services is preferable to

having them contribute funds to a central management agency that contracts for construction

of necessary components.

Different Legal Systems.–Nations also have

different legal systems that can complicate negotiations. Defining legal ownership of the experimental facility and of the information generated

there is a critical facet of a workable agreement.

Personnel Needs.–The staff of a joint undertaking will include participants from all programs

involved in the project, and administrative arrangements will have to accommodate their needs,

Currently, relationships between staff and their

respective governments differ over such issues as

the ability to sign contracts, intellectual property

rights, and compensation.

Staff for the project would come to a central

location from many countries and would in most

cases bring their families. They wouId expect,

without undue difficuIty, to find housing with access to shopping facilities and other amenities.
170 c Starpower: The U.S. and the International Quest for Fusion Energy

In particular, they would want an international,

rather than national, educational system for their

children. Moreover, most staff will return to their

home fusion programs after completion of their

assignments at the joint facility, and they will need

to be assured that their positions at home will remain available to them.

Management Approaches

If the conceptual design phase of the ITER project is successful, it could be followed by a decision to jointly construct and operate a major fusion

experiment. The prospects for such an activity

are being investigated by the major fusion programs. Any agreement to undertake such a project would be complex, and a variety of management and organizational issues could arise in

project negotiation and implementation. This section explores the applicability of management

structures developed for existing international

projects, both in fusion and in other areas, to the

potential collaborative fusion endeavor.

The organizational structure of a large-scale international project such as ITER depends on its

overall goals and objectives, which will be determined through negotiation. The main requirement for the organizational structure is that it define each participants’ degree of control over the

project by establishing such things as the project’s

technical and political decisionmaking procedures, the allocation of contributions and benefits among the partners, the degree of autonomy

between the collaborative project and the supporting domestic fusion programs, the arrangements for staff and contractors, and the routine

operation and long-range planning of the enterprise.

The degree of control that any participant exerts over the direction of the project can vary significantly, from minor technical influence to oversight of the entire project. Generally, however,

the amount of control a partner exercises is proportional to the amount of financial support it

provides. In the case of ITER, it appears likely

that financial support will be fairly evenly divided

among partners; thus, project control probably

will be shared by the partners.

The management structures of the existing cooperative projects examined below offer some

insight into how—or how not—to organize fusion

collaboration. Since each project’s goals are different, it is unlikely that any of these existing arrangements will be applicable as is for future fusion collaboration. Each project weighs its goals

and requirements independently, and, through

negotiation, unique trade-offs among competing

goals are made. Studying the organizational structures of existing international projects, however,

can be useful in exploring future projects such

as ITER.

International Tokamak Workshop (INTOR)31

Conducted under IAEA auspices, the INTOR

design study for a next-generation fusion experiment has features that may be useful for future

collaborative projects. INTOR has successfully enabled the international fusion programs to cooperatively develop a design for and explore the

technical characteristics of a next-generation machine. Moreover, the INTOR process was developed without causing concerns about national

security and is the most extensive cooperative fusion activity involving the Soviet Union. Since

INTOR is strictly a design effort, however, it provides no guidance for the construction and operation of future fusion collaborative experiments.

Joint European Torus (JET)32

The JET management structure is another approach for major collaborative projects. The JET

facility was designed and built by multinational

teams, is financed by the EC and the participating national fusion programs, and is managed by

a multinational council. The project has been successful, and the EC currently is exploring the possibility of using the same approach to manage a

next-generation experiment (the Next European

Torus or NET).

Though the JET approach has proven successful for European fusion collaboration, it is not

directly applicable as a model for ITER. First, the

JIThe I NTOR project is discussed in more detail on p. 159

Jzsee pp. 160-161 for a detailed description of JET.
Ch. 7. —Fusion as an /international Program s 171

JET agreement was negotiated within the existing umbrella structure of the European Community in which most of the administrative obstacles to international collaboration were already

resolved. Negotiating a major fusion cooperation

that included parties outside of the EC would be

significantly more complex because there is no

previously negotiated legal framework.

In addition, the JET approach was not designed

to provide a mechanism for limiting the transfer

of potentially sensitive technologies. Within the

JET framework, all participants have access to the

information and technology used or developed

in the project. Finally, the JET structure operates

through the cash contributions of participating

programs to its central management agency.

Hard currency transfers among the participants

in an ITER-type project would be more difficult

to arrange.

Large Coil Task (LCT)33

The Large Coil Task is a superconducting magnet testing project that has been conducted under the auspices of the IEA. The United States has

taken the lead on the project, financing construction of the magnet testing facility and three of the

six test magnets. The facility was designed jointly,

and three magnets were designed, constructed,

and financed by foreign participants in the

project. All information and non-proprietary technology used in construction of the test magnets

and all data generated through the experiment

are available to participating programs.

Although the LCT was not designed to preclude

information and technology transfer, its structure

could be slightly modified and used if limiting

such transfer was an objective. If a given task

were broken down into distinct components,

each subtask could be assigned to a partner who

would be responsible both financially and technically for its contribution. Provided that the “independent development” met technical specifications, each partner’s contribution could be

integrated into the overall machine, minimizing

exchange of information.

~lThe Large Coil Task IS described in more detail on p. 159.

This approach might resolve technology transfer concerns, but it could also introduce considerable difficulties into project management. Since

a primary goal of collaborating on a next-generation fusion experiment would be to make experimental techniques and results available to all

the cooperating parties, the independent development approach probably would not be acceptable in ITER. In addition, it would be difficuIt to

divide a major fusion project into isolated modules connected at interfaces; ITER probably will

be a complex and interrelated assemblage of systems and components. Moreover, coordinating

a project in which data and access were restricted

would require an extremely effective management team.

Another problem with applying the LCT model

to a future collaboration like ITER is control of

the project. In the LCT, the United States contributed most of the financial support and assumed principal technical control. For ITER, on

the other hand, it appears unlikely that any partner will assume the responsibility of becoming

project leader and shouldering most of the cost.

Thus, the management design of the LCT will not

be applicable to ITER.

Doublet Ill Project (D III)34

Doublet Ill is the most extensive cooperative

fusion project in which the United States currently is involved. The United States is the host

country for the Doublet project, and the Japanese have contributed over one-third of the funds

necessary to support the project i n recent years.

This direct contribution of currency distinguishes

the Doublet cooperation from other fusion activities in which the United States participates. The

project is jointly managed by a team of U.S. and

Japanese scientists; machine time and experimental results are shared equally between the

two nations. Doublet’s management structure has

distributed control of the project and financial

responsibility effectively among the Japanese and

American participants.

Several factors, however, may complicate the

use of the Doublet approach for more intensive

~~FOr mo~e detai led cj Iscussion of Doublet-1 I I D project, ~ee PP

162-163.
172 c Starpower: The U.S. and the International Quest for Fusion Energy

future undertakings. The scope of the project,

though extensive by U.S. standards, is quite limited when compared with the scale of potential

future projects such as ITER. Only two nations

are involved, and the amount of currency transferred is small compared to the projected cost

of ITER. Also, the original D I I I facility was an independent U.S. project, and the Japanese did not

become involved until the upgrades were undertaken. Thus, the Doublet project did not have to

address facility design and construction issues

from the beginning, as a completely collaborative project would.

European Laboratory for

Nuclear Research (CERN)35

CERN was established in 1954 by several Western European nations. Its objective was to advance knowledge in high energy physics, and it

has provided a framework for extensive cooperation in the design and construction of large-scale

experimental facilities. It has enabled the European nations to conduct physics research on a

scale that would have been impossible for any

of them acting independently.

CERN is coordinated by a council consisting

of two representatives—one administrative and

one technical—from each participating nation.

Participants make cash contributions to CERN

based on a percentage of each nation’s gross national product (GNP). No nation can contribute

more than 25 percent of CERN’s costs annually.

There are no “national rights” within the CERN

structure. Participating nations are not guaranteed particular positions for their representatives,

specified shares of CERN’s procurements, or priority for projects within CERN.

Many features of the CERN management structure could be attractive in future fusion cooperation. For example, the practice of making decisions

based on merit, not national rights or privileges,

is considered by many analysts to be responsible for CERN’s excellent technical record. In addition, involving both technical and administrative

people in decisionmaking has resulted in informed,

comprehensive decisions.

~SThiS dlcusslon based on pp. 92-93 of the National Research

Council report, Cooperation and Competition, op. cit.

Yet CERN, like JET, does not provide a complete model for a future ITER. First, CERN relies

on cash contributions, which may not be appropriate for ITER. Second, CERN does not have

mechanisms in place for protecting sensitive technologies. Third, some more formalized system of

“national rights, ” at least with respect to immediate economic return and longer term research

and development return, may be necessary to allocate the benefits of ITER among diverse economies that are not already as interdependent as

the individual European Community economies

are.

Space Station

The space station, a proposed multi-billion dollar orbiting facility, is the only attempt by the

United States to cooperate internationally on a

scale financially comparable to future fusion

plans. Under U.S. proposals for space station collaboration, the United States would take the lead

on the project and invite participation of others,

particularly Japan, Canada, and the European

Space Agency. Currency exchanges would be

minimal. Each of the programs would contribute

its own hardware to the station, and these contributions would be joined together at carefully

defined interfaces. Each program would retain essential control over development of its own hardware, but the United States would bear overall

responsibility for program direction and coordination, for overaIl systems engineering and integration, and for development and implementation of overall safety requirements. This approach

is intended to ensure compatibility and cooperation without transferring technology that the

partners may wish to protect.

Some aspects of the space station project could

provide a model for large-scale fusion collaboration. In particular, the space station may develop

a workable mechanism for limiting the undesirable transfer of technology among the participants.

In addition, it is likely that administrative aspects

of the agreement might have relevance to future

joint undertakings in fusion. Both the space station and a future fusion collaboration such as ITER

would have to address issues such as ownership

of equipment, intellectual property rights, dispute

settlement, liability, selection and assignment of
Ch. 7.—Fusion as an International Program ● 173

personnel, and establishment and maintenance

of safety standards. If the space station can resolve these issues successfully, it could provide

a model for ITER.

In many ways, however, it is difficult to apply

the space station approach to future fusion collaborations. The space station is designed to be

modular, with participants contributing independently developed components. As noted earlier,

the independent development approach would

probably be unacceptable and unworkable for

ITER. In addition, the United States is taking the

lead on the space station, dividing tasks and

shouldering much of the cost. It is not clear that

such an approach in a major fusion collaboration would be acceptable to either the United

States or other participants. Moreover, it is not

certain that the United States would accept a

subordinate role in a fusion collaboration if another

nation were to assume leadership of the project.

Fusion projects also have to address siting issues,

which the space station avoids because it is not

located on national territory. Finally, the space

station project does not include the Soviet Union,

and thereby avoids the additional security and

diplomatic concerns introduced by Soviet participation.

Summary of Potential Management

Approaches

It is unlikely that any existing cooperative

project will provide a model management structure for a major international effort such as

ITER. The strengths and weaknesses of existing

projects, with respect to large-scale fusion collaboration, are summarized in table 7-3.

Table 7-3.—Applicability of Existing Projects to Future Fusion Collaboration

Project Strengths Weaknesses

INTOR . . . . . . . . . . . . . .

●

JET . . . . . . . . . . . . . . . ●

LCT . . . . . . . . . . . . . . . ●

●

Proven approach to project design phase ●

Most extensive fusion collaboration

involving the Soviet Union

Successful design, construction, and ●

operation of world-class facility

●

Successful joint research project ●

Could provide for control of technology

transfer ●

D Ill . . . . . . . . . . . . . . . ● Successful management structure

CERN . . . . . . . . . . . . . c

●

Space Station . . . . . . ●

Successful design, construction, and

operation of world-class high-energy

physics program

Not bound by “national rights” system

Successful conclusion of negotiations will

show that large-scale, multi-year, and

multi-billion dollar collaborations can be

established by the United States

●

●

●

●

●

●

●

●

●

●

Poorly suited for construction and operation

Negotiated within preexisting cooperative

framework

Might not address technology transfer issues

adequately

United States was lead agency and bore

majority of costs

“Independent development” approach might

be unworkable for ITER

Might not ensure technical equality of

participants, depending on distribution of

tasks

United States was lead agency and bore

majority of costs

Small-scale project when compared with

ITER

Joint project dealt only with upgrade of

previously constructed experiment

Involves hard currency transfer

Involves hard currency transfer

Might not address technology transfer issues

adequately

Lack of “national rights” system may limit

equitable allocation of project benefits

Negotiations have not been finalized

Independent developments approach might

be unworkable for ITER

Does not address siting issues

Provides no experience with Soviet

participation

SOURCE: Off Ice of Technology Assessment, 1987
174 ● Starpower: The U.S. and the International Quest for Fusion Energy

COMPARISON OF INTERNATIONAL FUSION PROGRAMS

Comparing levels of effort among the international fusion programs is complex. Qualitative

measures show that the programs are similar in

direction and achievement, but these measures

are subjective. Quantitative measures are more

objective, but they may be distorted. Moreover,

different techniques give different results.

Qualitative Comparisons

Qualitative comparisons show that the four major fusion programs are comparable in levels of

effort and accomplishment and in their near-term

research objectives, although the stated long-term

goals and rationales for the programs differ (see

table 7-4). Three of the programs operate tokamak experiments of similar capability and complexity, and the fourth (the Soviet Union) is in

the process of building a large tokamak of somewhat similar capability; each program also studies

alternative confinement concepts. All of the programs recognize the need for a next-generation

experiment during the mid-1990s to advance fusion technology and science.

Table 7-4.—Program Goals of the

Major Fusion Programs

Program

Goal Rationale

U s .

Demonstrate science and

technology base for

fusion power

EC

Prototype construction

Japan

Demonstration plant

U.S.S.R.

Fusion hybrid systema

Determine potential as an

energy option

Develop energy option

Promote industrial

capability

Strengthen political unity

Develop energy option

Fulfill national project

Support fission program

Maintain international

activity

aFusion hybrids are discussed in app. A.

SOURCE Michael Roberts, Director of International Programs, U.S. Department

of Energy, Office of Fusion Energy, briefing on “lnternatlonal Discus.

sions on Engineering Test Reactor, ” before the ETR Workshop, Rockvine, MD, July 16, 1966

Figure 7-1 compares the programs’ research

and development emphases on confinement concepts, and figure 7-2 compares their technology

development efforts.36 Variations among programs

are influenced by differing program concentration, funding levels, technological capabilities,

and program history.

Quantitative Comparisons

There are a variety of ways to compare quantitatively the levels of effort among the U. S., EC,

and Japanese fusion programs, but each way has

flaws. (Data for the Soviet Union is not included

in this discussion; it is difficult to obtain reliable

information on the size of the Soviet program,

its funding level, and the number of people it employs.) Figure 7-3 compares DOE’s estimates of

the annual fusion budgets of the three programs

converted into dollars. According to this figure,

the United States has had the highest level of effort in fusion research. However, this conclusion

is dependent on the exchange rates used in the

currency conversion. The relative magnitude of

the U.S. effort is due in part to the extraordinary

strength of the dollar in the mid-1980s with respect to European and Japanese currencies. To

the extent that goods and services purchased with

fusion research funds are not traded on international markets, fluctuations in exchange rates distort the calculations of relative expenditures. Sudden shifts in the value of the dollar have dramatic

effects on dollar-based comparisons of the fusion

budgets, but do not represent actual changes in

fusion work effort.

To correct for distortions from fluctuating exchange rates, DOE has used another method to

compare fusion programs.37 In this method, the

}bThe discussion I n this and the following paragraph is based on

documentation by Dr. Stephen 0, Dean, President of Fusion Power

Associates and author of figures 7-1 and 7-2. His insights represent

a view commonly held by the fusion community regarding the relative levels of effort among the major fusion programs. The technical characteristics of the confinement concepts are explained in

ch. 4.

JTjohn Willis, U.S. Department of Energy, Office of Fusion Energy,

Oc. 9, 1986, personal communication to OTA.
Ch. 7.—Fusion as an International Program ● 175

Figure 7-1.— Emphases of Major Programs on Confinement Concepts, 1986

us

JAPAN

USSR

EC

Figure 7.2.–Emphases of Major Programs on Technology Development, 1986

SOURCE Fusion Power Associates.

fusion budget of each program is divided by the This figure does not literally represent the numaverage annual manufacturing wages prevailing ber of people employed by the respective fusion

in the country or region, with both values meas- programs, but rather represents an arbitrary means

ured in local currency. The resulting value is a of comparing relative levels of effort. Expenditures

measure of the level of effort of each program on construction and operation of facilities are

in units of “equivalent person-y ears.” Compari- converted, along with actual personnel costs, into

sons are shown in figure 7-4. “person-years” of effort. The validity of this meas-
176 ● Starpower: The U.S. and the International Quest for Fusion Energy

Figure 7-3.—Comparison of International Fusion Budgets (in current dollars)

1980 1981 1982

■ United States ❑ European Community

SOURCE: U.S. Department of Energy, Office of Fusion Energy, 1986,

ure depends on how well the quoted manufacturing wage rates reflect the wages relevant to the

fusion program, on how similar the productivity

of labor is between programs, and on how similar the relative values of capital and labor expenditures are among the three programs.

Figure 7-4 shows that by this measure, both the

Japanese and the U.S. levels of effort dropped

slightly from 1980 to 1986. In both programs, the

fusion budget rose in real dollars. However, increases in the average industrial wage rate over

the same period resulted in a substantial drop in

1983

Year

❑ Japan

1984 1985 1986

“equivalent person-years." 38 Unless the majority

of the costs incurred by the Japanese and U..S.

fusion programs actually rose by the same amount

as the wage rate, the conversion to “equivalent

person-years” overestimates the decline in these

fusion efforts.

 programs, the average industrial wage 

1980 to 1986 rose 38 percent in the United States, rose 76 percent

in Japan, and fell 6 percent in the European Community. Over the

same period, the fusion budget rose only 4.6 percent in the United

States, rose 24 percent in Japan, and rose 97 percent in the European Community, in real dollars.
Ch. 7.—Fusion as an International Program . 177

32

30

28

26

24

22

20

18

16

14

12

10

8

6

4

2

0

Figure 7-4.—Comparison of International Equivalent Person-Years

1980 1981 1982

OTA used a third method of comparison to

construct figure 7-5, which illustrates the fusion

budgets as a percentage of each program’s GNP.

Under this method, the fusion budgets, as reported

by DOE, are divided by the national GNP.39 Although all values are converted to dollars, inaccuracies in the conversion process should not affect the final result since both GNP values and

fusion budgets were adjusted. This approach,

which shows that the Japanese devote the greatest proportion of their resources to fusion, measures the relative level of effort of fusion research

 European Community was calculated by adding

the GNPs the member 

1983 1984 1985 1986

Year

Japan

compared to the rest of the economy of each

party. It does not present a comparison of absolute levels of effort, but might be taken to indicate some measure of the commitment of each

nation to its fusion program. Of course, many external factors that strongly influence each nation’s

spending priorities cannot be shown in this figure. For example, this figure does not show the

great asymmetry in defense expenditures of the

various nations.

An additional problem confounds all of the

quantitative methods: the calculations are based

on program budgets that are not directly comparable. Budget figures provided by the Japanese
178 ● Starpower: The U.S. and the International Quest for Fusion Energy

0.004

0.002

0

1980 1981

■ United States ■ European Community

SOURCE: Office of Technology Assessment, 1987

Government, for example, do not include personnel costs. In the figures shown here, these

costs were estimated by DOE for the Japanese

program and added to the Japanese figures. In

the EC and the United States, distinctions must

be made between budget authority (how much

the program was authorized to spend) and budget outlay (how much the program actually did

spend), and these values can be substantially

different.

Obviously, quantitative level-of-effort comparisons based on budget levels may not be reliable. Each method of analysis discussed here suggests different results, and no conclusions can be

drawn.
Ch. 7.—Fusion as an /international Program . 179

POTENTIAL PARTNERS

Since DOE is investigating the possibility of increased levels of collaboration, an analysis of the

goals and incentives of the potential collaborative partners is important.

The United States

Program Goals

The stated goal of the U.S. fusion program is

to establish the scientific and technological base

necessary to evaluate the potential for fusion

energy by early in the 21st century. In 1988, design and construction of the next major facility,

the Compact Ignition Tokamak (CIT), may begin,

if approved by Congress. The United States recognizes the need to have an engineering test reactor by the mid-1990s to study technical issues

related to reactor design and operation, but, due

to funding limitations, DOE would like to construct such a reactor in collaboration with one

or more other fusion programs. In the conceptual design and supporting R&D proposal currently being negotiated, this project is called the

International Thermonuclear Experimental Reactor (ITER). The U.S. fusion program does not

currently have plans to construct an engineering

test reactor independently. Beyond a collaborative engineering test reactor, the U.S. program

has no plans to construct a demonstration reactor. 40

Views on Collaboration

The United States is extremely interested in future international collaboration, particularly on

construction and operation of ITER. A primary

incentive is financial; at present, the domestic fusion program is not able to command the financial resources necessary to construct experiments

of this scale by itself. Another incentive is DOE’s

belief that a well-developed scientific and technological base for fusion will be easier to establish if the major fusion programs share information and expertise.

At this point, the U.S. fusion program is considering the possibility of collaborating on ITER

with any or all of the major fusion programs. Of

the major programs, the United States has cooperated most extensively with Japan. Formal ties

between the United States and the European

Community are more recent, but the EC fusion

program is highly advanced and would be an attractive partner. The U.S. fusion community also

highly values input from its Soviet counterpart,

which has made significant contributions to past

cooperative projects and which continues to

make technological advances. However, the politics of the U.S.-Soviet relationship are more volatile than those between the United States and Japan or the EC. This difference will make major

collaboration with the Soviet Union the most difficult to arrange.

Nevertheless, Soviet participation in a multilateral fusion project has been supported at the

highest levels of both governments. At the Geneva

Summit of 1985, President Reagan and General

Secretary Gorbachev “advocated the widest

practicable development of international collaboration” in fusion research .4’ The United States

explicitly made this arrangement conditional

upon allied participation, and a strictly bilateral

collaboration between the two countries on ITER

would be very unlikely.

q~see the Section Ot ch, 4 titled ‘‘Research Progress and Future

Directions” for a more detailed cliscussion of the U.S. research plans

and facility needs.

~1 From statement at the Reaga n-Gorbache\ Sum m It, November

1985.
180 ● Starpower: The U.S. and the international Quest for Fusion Energy

The European Community42

Program Goals

The member countries of the European Community are making a long-term investment in fusion for its possible value as a major new energy

source that could contribute to Western Europe’s

future energy security. Collaboration within the

EC has been extremely successful; it has been a

source of pride.

The joint European Torus (JET) is the EC’s most

important experimental fusion facility and the

world’s largest tokamak.43 Planning has begun for

a second facility—the Next European Torus (NET)

—which, like ITER, is intended to confirm the scientific feasibiIity of fusion and address the question of engineering feasibility. The current schedule for NET calls for a detailed design decision

in 1989 or 1990 and a decision on construction

in 1993. A third facility envisioned by the EC is

a prototype fusion power reactor to demonstrate

the economic feasibility of fusion. The timetable

for this prototype depends on the success of JET

and NET. Construction is projected to begin between 2010 and 2020.

Views on Collaboration

The European Community is interested in international collaboration for a variety of reasons.

In recent years, the EC has confronted tight

budgets and competing demands for funding,

which increase the attractiveness of working with

partners outside of Europe. Like other nations,

the EC recognizes the substantial benefits of cost

savings and knowledge and risk sharing. Moreover, through the JET project, the EC has had

positive first-hand experience with the scientific,

technical, and management aspects of collaboration. In addition, the EC fusion effort has cooperative relationships with the other programs,

principally the United States for which it has considerable respect. It also respects the Soviet and

qzThi5 discussion is based in part on information provided by an

OTA contractor, Professor Wilfrid Kohl, in a report titled “The Political Aspects of Fusion Research in Europe.” Kohl IS director of

the International Energy Program at the Johns Hopkins University

School of Advanced International Studies.

JJThe j ET project is de5cribed I n cfeta i I i n ‘‘Mu ki Iaterat Activities.

Japanese fusion programs, but contact with them

has been less frequent.

Even without international collaboration, the

European Community’s program has established

political support and momentum through JET.

The EC has a clear strategy for future fusion research, in which NET plays a vital role, and it appears committed to carrying this program out.

Nevertheless, the European Community is willing to investigate prospects for a large-scale collaboration with the other major fusion programs.

At the same time, the EC plans to continue working independently on NET unless and until the

ITER effort offers convincing guarantees of success. The EC might not wish to participate in a

major project that is not located in Europe.

The Soviet Union44

Program Goals

The Soviet Union has an active fusion research

program, which is supported by a strong commitment to nuclear power for geographical and

fuel cycle reasons.45 The breeder reactor is the

primary focus of the Soviet atomic energy program for the 199os, and the fusion reactor is the

focus of the next century. The Soviet Union is

also investigating the potential of fission-fusion

hybrid reactors for its thermal and breeder reactor

program .46

The Soviet Union is currently constructing a

major tokamak experiment, T-15, which is similar in objective and capability to the large tokamaks currently being operated in the United

States, EC, and Japan. Completion of T-15 was

441 nformation on the Soviet Union’s fusion program was provided

to OTA by Dr. Paul Josephson, “The History and Politics of Energy

Technology: Controlled Thermonuclear Synthesis Research in the

USSR. ” Josephson has studied Soviet science and technology policy issues at the Massachusetts Institute of Technology’s Program

in Science, Technology, and Society.

dsseventy percent of Soviet energy consumption and POPU Iatlon

is located in the European part of the country, but 90 percent of

the fuel resources are located in Siberia and Soviet Central Asia.

The cost of transporting the energy thousands of miles from east

to west, either in its primary form or as electricity, is high. Therefore, the government is pursuing the rapid commercialization of

nuclear energy near the western population centers.

aGFission-fusion hybrid reactors use the neutrons generated in fusion reactions to produce fissionable fuel. For more information,

see app. A.
Ch. 7.—Fusion as an International Program ● 181

originally scheduled for 1982, but the project has

been delayed repeatedly due to engineering

problems and is now expected to operate in

1988. The Soviets are considering construction

of a device called the Operational Test Reactor

(OTR) to succeed T-1 5.47 This device is believed

to be analogous to the next-generation devices

planned in other major national programs, except that it is also intended to verify how effectively fusion can be used to breed fuel for fission

reactors.

Views on Collaboration

The Soviet Union has regularly made proposals

to enhance international cooperation in fusion.

The INTOR project was initially proposed by the

Soviets, as was the genesis of the current proposal

for an international next-generation experiment.

The Soviet Union has made major contributions

to past international projects and has clearly

found the activities rewarding.

It appears that budgetary constraints are putting pressure on the Soviet fusion program. While

it is difficult to provide actual data on the size

of the Soviet fusion budget, a review of Soviet

journals indicates that plasma physicists currently

are more circumspect in their predictions for fusion power than they used to be, and that they

are fighting to retain their fusion budgets in the

face of intense pressure from other energy research programs such as breeder reactors. 48

There is high-level political support for collaboration in fusion, and General Secretary Gorbachev

has stressed repeatedly its importance. He raised

the issue with President Reagan at the Geneva

Summit in 1985 and again in a speech before the

Supreme Soviet in 1986. On the latter occasion,

he said:

On the initiative of the U. S. S. R., work involving scientists from different countries has begun

on the tokamak thermonuclear reactor project

[lNTOR], which opens up an opportunity to radically resolve the energy problem. According to

scientists, it is possible to create as early as within

~7MlCha~l RO&rlS, U, S. Department of Energy, (] ftlce Of Fusion

Ener~y, brlet’lng o n ‘‘International Dlscus\ions on ETR, ” Rock\ llle,

MD, jU]Y 16, 1986 .

48P, Josephson, “H I$tory and Politics, ” op. cIt,, pp. 16-19.

this century a terrestrial sun . . . thermonuclear

energy. We note with satisfaction that it was

agreed in Geneva to carry on with that important work.49

In addition to incentives to collaborate, there

are also obstacles from the Soviet perspective.

These include pressures within the U.S.S.R. to

avoid technological reliance on the West and

shortages of hard currency with which to participate. Another obstacle is any unforeseen deterioration of the U.S.-U.S.S.R. relationship due to

political developments unrelated to fusion; in

1980, for example, the Soviet invasion of Afghanistan interrupted cooperative fusion work

that had been relatively stable until then.

It appears that the Soviets would be comfortable collaborating with any of the major fusion

programs on ITER, judging from the positive Soviet evaluation of INTOR. However, as yet neither the Japanese nor the Europeans have sought

to build a machine with the Soviets.50 Because of

the Soviet Union’s relatively long-term involvement with the United States in bilateral scientific agreements, the role of these scientific exchanges in the pursuit of improving relations,

the present international outlook of Soviet leaders

toward technology, and Soviet respect for American science and technology, the Soviets appear

interested and willing to collaborate with the

United States.

Japan

51

Program Goals

Many Japanese see fusion as the ultimate solution to Japan’s energy problems. Japan is more

dependent on imported energy than any other

major economic power, and the Japanese are

concerned about how precarious this dependence makes their economy. Nuclear energy has

49M S. GOrbac hev, as cited I n Kadomtw\, ‘‘ Toka ma k, SOL let

L/fe, August 1986, p. 13.

50Mark Crawford, “Researchers’ Dreams Turn to Paper In U.S -

USSR Fusion Plan, ” Science, vol. 234, Nov. 7, 1986, p. 667

5)Thls section IS ba~ed In part on a report completed for OT A

by Dr. Leonard Lynn, “Politlcal Aspects of Fusion Research In japan, ” Lynn IS a proiessor who analyzes Japanese science and technology pollcy I n the Department oi Social and Decision Sciences

at Ca rnegle-Mel Ion U n[verslty.
182 ● Starpower: The U.S. and the International Quest for Fusion Energy

helped the Japanese decrease their dependence

on oil, and Japanese policy makers favor the continued use and development of nuclear power.

Japan’s general long-range energy policy calls for

an increased reliance on conventional nuclear

energy over the next 25 years. It is anticipated

that this policy will be followed by a reliance on

fast breeder reactors around 2010 and a transition to fusion energy about 30 years later.

The largest experimental fusion facility in Japan is JT-60. Japanese scientists have begun conceptual design studies for a next-generation tokamak, the Fusion Experimental Reactor (FER),

which is intended to succeed JT-60. FER, which

could be built in the late 1990s, would resemble

NET or ITER and probably would be designed to

achieve ignition and demonstrate the technical

feasibility of the nuclear fusion reactor.

Views on Collaboration

International collaboration is attractive to the

Japanese for many of the same reasons that it is

attractive to other countries. The Japanese, like

others, feel that the financial and human resources

required to construct a next-generation fusion device may be too great a burden to bear alone.

Moreover, the Japanese have both contributed

and received valuable technical information from

past fusion cooperative projects.

Although the Japanese are interested in collaborating on fusion research, there maybe some

obstacles to such collaboration. The Japanese

confront a major debt burden that has grown rapidly in the last few years and that has increased

government pressure to cut spending.52 In addition, the Japanese might be unwilling to participate if the experiment is not sited in Japan.

The Japanese are willing to explore the possibility of multilateral collaboration on ITER, however, and they are currently participating i n discussions of the project with the United States, the

European Community, and the Soviet Union. Of

the three, Japan appears most interested in collaborating with the United States. In addition to

extensive cooperative experience with the United

States, the Japanese also have a bilateral arrangement with the EC that involves meetings of experts and information exchange.53 However, the

Japanese and European programs currently are

less familiar with each other than either is with

the United States. The Japanese have the least

experience cooperating with the Soviet Union.

Jzlbid,, ~p, 46.47: public debt climbed from 2.2 trllllon Yen In 1976

(13 percent ot’ GNP) to 130 trillion yen in 1985 (42 percent of GNP),

In 1986, the cost of servicing this debt accounted for more thdn

20 percent of government expenditures. This compares to 14 percent of government expenditures going to service the U.S. national

debt in 1985.

5Jlbid., pp. 42-43.

PROSPECTS FOR INTERNATIONAL COOPERATION

U.S. Plans for Future Cooperation International collaboration in fusion research

and development has become a key factor in

DOE is interested in the prospects for more ex- DOE’S program planning.

tensive international cooperation on future magnetic fusion experiments. In fact, a recent DOE Possible Areas for International

report on international activities in magnetic fu- Cooperation

sion states:

There are several possible areas of cooperation

The objectives of U.S. international collabora- delineated in DOE’s report. 55 These areas are

tion are to share the many high priority tasks, to linked to the four key technical issues in the DOE

reduce the total costs associated with the required Magnetic Fusion Program Plan (see the section major facilities and to combine intellectual forces

in pursuit of the most essential problems.54 in ch. 4 titled “Key Technical Issues and Facilities” under “Research Progress and Future DirecJ~U .s, Depaflnlent of Energy, Office of Fusion Energy, /nte~na -

fiorra/ Program Activities In Magnetic FusIorr Energy, op. cit., p. 1. ~Jl bid., Attachment 3, pp. 1-5.
tions”). In confinement systems, DOE states that

possible initiatives include gaining long-term access to the JET experimental programs and possibly those at JT-60, developing a coordinated

program to develop the reversed-field pinch concept, and using selected foreign facilities to continue development of superconducting magnets.

in burning plasmas, the United States would seek

foreign participation in the planning and operation of CIT. In nuclear technology for fusion systems, DOE is investigating proposals to extend

the current cooperative activity in technology research and development and to coordinate efforts in development of tritium handling technology. In fusion materials, DOE further proposes

to coordinate research with the other major

programs.

Considerations of the International

Thermonuclear Experimental Reactor

To date, DOE’s proposal to design ITER collaboratively has drawn the most attention among the

many cooperative efforts outlined in DOE’s report.

Within the framework of the Versailles and Geneva

summits, DOE has been involved in negotiations

with the other major fusion programs to develop

the conceptual design and supporting R&D for

ITER. The proposal does not currently extend to

joint construction and operation of the experimental faciIity. At the conclusion of the conceptual design effort, the parties would be free to

build such a device, either alone or collectively.

The Versailles Economic Summit.—Several nations participate each year in an economic sum-
184 ● Starpower: The U.S. and the International Quest for Fusion Energy

mit meeting.56 These nations began considering

the implications of technology for economic

growth and employment at the urging of French

President Mitterand in 1982 when the meeting

was held in Versailles, France, and a process for

considering specific ideas on this topic was established. The prospect of international cooperation

in magnetic fusion was one of 18 ideas specifically investigated. Cooperative efforts in fusion

research have been discussed since then, and a

great deal of effort has gone into developing plans

for a workable joint undertaking.57

Under the framework established at the Versailles summit, the Fusion Working Group was

created in 1983. The Fusion Working Group is

involved in early joint planning efforts and discussions aimed at identifying necessary major facilities. in 1985, the Fusion Working Group created the Technical Working Party to consider

technical and research-related issues in international fusion projects. In late 1985, the Technical Working Party endorsed the U.S. plan to construct CIT.

In 1986, the Fusion Working Group reached

a consensus on the desirability of future collaborative activities. Participants issued a joint statement

that an engineering test reactor (now called ITER)

is a common midterm goal for the fusion programs of the United States, Japan, and the European Community.58

The Geneva Summit.–Fusion cooperation was

also discussed by the United States and the Soviet Union at the Geneva summit in November

1985. Prior to the summit, in an October 1985

meeting between French president Mitterand and

Soviet General Secretary Gorbachev, Gorbachev

had expressed interest in pursuing international

collaboration on a large next-generation fusion

experiment. The Geneva summit between President Reagan and Gorbachev, held in Geneva,

Sbparticipants are the united States, Canada, the Federal f@ubIic of Germany, France, Italy, Japan, and the United Kingdom. The

European Community as a whole is also represented.

SzMlchael Roberts, Director of International Programs, U.S. Department of Energy, Office of Fusion Energy, briefing on “international Programs in Fusion, ” presented to ERAB Fusion Panel, Washington, DC, May 29, 1986.

WSU mmlt Working Group on Controlled Thermonuclear Fusion,

Summary Conclusions, Schloss Ringberg, Jan. 17, 1986.

Switzerland, followed up on this point. At the

conclusion of the meeting, President Reagan and

General Secretary Gorbachev issued a joint statement supporting fusion collaboration to the “widest

degree practicable.” The statement did not recommend a specific proposal or approach.

Current Status of the ITER Project.–No formal agreement has been reached on the ITER

project. Recently, the United States proposed that

the potential partners begin a 3-year joint planning activity to do conceptual design and supporting R&D for the device. Areas of collaboration would include defining the scope of the

project, developing a conceptual design for the

device, and coordinating the research needed to

support the design effort.

Representatives from the United States, Japan,

the European Community, and the Soviet Union

met in March 1987, in Vienna, Austria, to discuss

the conceptual design phase of such a project.

This meeting, held under IAEA auspices, marked

the first time that all four parties met to discuss

collaboration on ITER. The meeting produced

general agreement on the nature of the project

“and the necessary steps to formalize it. The IAEA

stated at the end of the meeting:

The Parties were favorably disposed to the proposal for joint conduct of conceptual design and

supporting R&D for an international thermonuclear experimental reactor. The Parties reached

an understanding that the proposal was a sound

basis for further discussion. The four Parties will

each identify their representative to a group of

experts to make proposals for a common set of

detailed technical objectives for the conceptual

design and to prepare the basis for further consideration by the Parties .59

In some ways, the arrangement proposed by

the United States resembles the International

Tokamak Reactor (lNTOR) study. The proposal

is more extensive, however, than INTOR. First,

ITER deliverables would have a defined schedule, whereas the INTOR schedule is indefinite.

Second, the ITER project would receive higher

level attention than INTOR. Third, under the ITER

WI nternational Atom ic Energy Agency, as quoted i n hecutive

Newsletter, Fusion Power Associates, April 1987, p. 4.
Ch. 7.—Fusion as an International Program . 185

project, there would be full-time design teams

working in each program; the INTOR design

teams are part-time. Finally, the ITER project, unlike INTOR, would include cooperation on supporting R&D.

DOE has proposed that there be a full-time

group of managing directors to coordinate the

planning effort. According to DOE, this phase of

the activity could utilize the International Atomic

Energy Agency as an umbrella organization to facilitate the project. For simplicity, the coordinating site could be located at the IAEA headquarters in Vienna, Austria. No other site agreements

would be necessary at this stage because all other

work would be undertaken within the national

programs.

The total cost of the 3-year conceptual design

phase of ITER is estimated to be between $150

million and $200 million, which includes its supporting R&D. The U.S. cost of the undertaking

is projected at between $15 million and $20 million annually. This annual budget represents

about a tripling of the amount the United States

currently spends on design studies.

DOE anticipates that the conceptual design

phase of the ITER project will occur between

1988 and 1990. At the completion of this phase,

interested parties would be in a position to begin negotiations on whether or not to jointly construct and operate the device. Any party could

withdraw at this point, decide to construct and

operate the experiment independently, or choose

to pursue the effort collaboratively.

Analysis of U.S. Proposal for ITER

The U.S. Government’s recent proposal marks

the first step toward a collaborative ITER. No

agreement has been reached; the details of the

proposal will be modified during negotiations

with other fusion programs. Therefore, it is impossible to assess the proposal completely.

The proposal is based on the INTOR model,

which provides an example of successful, if limited, cooperation on project design. Like INTOR,

in which the Soviet Union participates without

threatening U.S. national security, this proposal

does not raise technology transfer concerns because it will include only common design, not

common technology development.

The current proposal does not address the

problems that would be encountered in jointly

constructing and operating ITER. These obstacles will still arise when and if the decision is

made to build and operate the device. The current proposal does provide a mechanism whereby

the conceptual design and supporting R&D can

be completed, enabling informed decisions about

proceeding with collaboration to be made at a

later date.

Completing the conceptual design phase of

ITER may help resolve some of the obstacles to

subsequent collaboration. For example, the conceptual designs developed over the next 3 years

may enable concerns about technology transfer

to be analyzed specifically and their implications

for national security to be resolved definitively.

Furthermore, issues such as siting the facility or

determining a technically acceptable project design may be settled, either through the initial

phase of the project or through concurrent discussions and negotiations. At the completion of

the design phase, the major fusion programs

should be better situated to develop detailed

plans for further collaboration.

The current ITER proposal begins conservatively, utilizing an already well-established cooperative arrangement. Participants will be able to

work on the project without making a firm commitment to future involvement in joint construction and operation. Perhaps most importantly,

U.S. Government agencies will have more time

and additional information with which to establish clear policy guidelines.

SUMMARY AND CONCLUSIONS

Magnetic fusion has a long history of interna- costs, risk, and knowledge; they value the opportional cooperation. For the future, the major fu- tunity to achieve collectively what no program

sion programs recognize the benefits of sharing could afford to achieve alone. Any or all of the
— —

186 “ Starpower: The U.S. and the International Quest for Fusion Energy

major world fusion programs would be technically attractive collaborative partners for the

United States. Higher levels of cooperation have

drawbacks, however. Cooperation may actually

increase the total cost and risk associated with

fusion projects, and the benefits of knowledge

sharing may be cut short if technology threatening national security or national competitiveness

is transferred to the partners.

There are many successful examples of cooperation in fusion research and other scientific

areas. JET, for example, is a collaborative undertaking in which the major European fusion programs have jointly constructed and operated a

world-class tokamak facility. CERN, a major nonfusion project, is an example of the European nations pooling their resources and developing a

state-of-the-art high-energy physics program.

While future cooperation can build on the solid

foundation of the past, collaborative projects such

as ITER will have to resolve many new issues. Collaboration on this scale involving countries outside Europe is unprecedented. Negotiating and

approving the necessary international agreements

will be possible only if the parties involved are

committed both to the collaborative project and

to their domestic programs. International collaboration cannot substitute for a domestic fusion program. If the domestic program is sacrificed to support an international project, the rationale for

collaboration will be lost and the ability to conduct

the project successfully will be compromised.

The U.S. Government’s current ITER proposal

appears to be a workable first step toward a major experimental facility. The proposal minimizes

the risks in the project’s early stages by decoupling

design from construction and operation.

The proposal has far to go. Although successful

completion of the conceptual design and supporting R&D will be important for addressing the

issues related to construction and operation, the

design process alone will not resolve these issues.

In the United States, at the moment, the most significant issue on joint construction and operation

is the possible transfer of militarily relevant technology. Agencies within the U.S. Government

disagree about the severity of this problem, and

the dispute must be settled internally before a major collaboration can proceed.

project location is another critical issue. Just as

siting was a major problem for JET, it is likely that

a decision on ITER location will not come easily. What does seem clear is that it is unlikely that

either the United States or the Soviet Union will

be chosen as the site for ITER.

Ultimately, reaching an agreement to jointly

construct and operate an international experiment will require high-level government support.

A clear presidential decision to support the undertaking will be required. Even that, by itself, is insufficient to guarantee the viability of a project

involving all branches of the U.S. Government

and extending over several Presidential Administrations. Moreover, the national programs will

have to formalize their support in an agreement

that will establish confidence in the management

and operation of the project.

DOE considers international collaboration on

ITER and other projects essential to the progress

of the U.S. fusion program. If more extensive cooperation proves impossible or unacceptable,

DOE’s program plans must be reevaluated: either the U.S. program will need more funding or

its schedule will have to be slowed down and

revised.
Chapter 8

Future Paths for the 

Magnetic Fusion Program 
CONTENTS

Key Issues Affecting the

The Independent Path .

Description. . . . . . . . .

. . . . . .

. . . . . .

Motivations and Assumptions

The Collaborative Path . .“. . . . .

Description. . . . . . . . . . . . . . .

Motivations and Assumptions

The Limited Path. . . . . . . . . . . .

Description. . . . . . . . . . . . . . .

Motivations and Assumptions

The Mothballed path . . . . . . . . .

Description. . . . . . . . . . . . . . .

Motivations and Assumptions

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

. .

Page

of Fusion Research . . . . . . . . . . . . . . . . . . . . .189

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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191

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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196

● . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196

● . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196
Chapter 8

Future Paths for the

Magnetic Fusion Program

The likelihood that fusion will be developed as

a future energy supply option is affected—although

not completely determined—by policy choices

made today. A decision to accelerate fusion research does not ensure that fusion’s potential will

be successfully realized, any more than a decision to terminate the current research program

implies that fusion will never be developed.

Nevertheless, near-term decisions clearly influence the pace of fusion’s development. The

sooner we wish to evaluate fusion as an energy

supply technology, the more important our nearterm decisions become. Over the next several

decades, the fusion research program can evolve

along any of four largely distinct paths:

1. With substantial funding increases, the U.S.

fusion program can complete its currently

mapped-out research plan independently.

This plan is intended to permit decisions

concerning fusion’s commercialization to be

made early in the next century. This approach

is called the “Independent” path.

2. At only moderate increases in U.S. funding

levels, the same results might be attainable–

although possibly somewhat delayed—if the

United States can work with some or all of

the world’s other major fusion programs

(Western Europe, Japan, and the Soviet

Union) at an unprecedented level of collaboration. This path is termed ‘‘Collaboratii’e.

3. In the absence of major collaboration, a flat

or declining funding profile wouId force significant changes to be made in the program’s

overall goals, including a recognition that fusion’s commercialization would be delayed

from current projections. This path is called

“Limited,” indicating that progress in some

critical areas wouId be impossible without

additional resources.

4. Shutting down the fusion program would

foreclose the possibility of developing fusion

as an energy supply option unless and until

research were resumed. On this “Moth -

balled” path, progress towards fusion in the

United States would halt. Work would probably continue abroad, although possibly at

a reduced pace; resumption of research in

the United States would be possible but difficult.

Current Department of Energy long-range

plans for the fusion program are aimed at the

“Collaborative” path. If recent funding declines

continue, however, or if the United States does

not successfully arrange its participation in major collaborative activities, the U.S. fusion program will evolve along the “Limited” path.

KEY ISSUES AFFECTING THE EVOLUTION OF FUSION RESEARCH

The four paths are differentiated by the degree

of commitment and the level of funding provided

by the U.S. Government for fusion research. Path

characteristics and the choices between them are

determined by several factors, including: 1 ) the

likelihood of technical and commercial success

in developing fusion technology; 2) the perceived

urgency with which a new supply of electricity

is needed; 3) the advantages and risks of largescale international collaboration; 4) the implications of requirements for expensive research facilities; and 5) the value of the “auxiliary benefits” associated with fusion research such as

scientific understanding, education, and technological development. Another factor, the potential for surprise inherent in any new technology,

189
190 . Starpower: The U.S. and the International Quest for Fusion Energy

may also be an important aspect of one’s choice

of research approach; however, such a factor is

not amenable to analysis.

Discussions earlier in this report have addressed

many of these factors, which are summarized

below:

●

●

Likelihood of Success: In evaluating the likelihood of program success, technical success

must be differentiated from commercial success. According to chapter 4, the risk of technical failure appears small, particularly if

operation of the Compact Ignition Tokamak

(CIT) does not uncover serious problems.1

If CIT operates as anticipated, it seems likely

that a fusion device capable of producing

electricity can be developed.

However, the risk of commercial failure—

the development of a technology that does

not interest potential users—is much harder

to evaluate. The commercial attractiveness

of fusion energy will depend not only on its

cost, but also on conditions unrelated to fusion technology that cannot be estimated at

present. Different opinions as to the likelihood of successful commercialization and

the attractiveness of fusion over other electricity alternatives affect the priority given to

fusion research.

Perceived Urgency: Chapter 5 concluded

that estimates of future electricity demand

neither require nor eliminate fusion as a possible energy source. It appears that electricity technologies other than fusion—principally

coal and nuclear fission—should be capable

of supplying ample power at reasonable

prices through at least the middle of the next

century. However, uncertainties as to the

continued acceptability of fossil fuels and nuclear fission provide incentives to explore the

potential of improved energy efficiency and

to develop alternative energy sources. Different estimates of the future attractiveness of

coal and nuclear fission, and different judgments of the ability of various alternatives to

ICIT is described in the section of ch. 4 titled “Key Technical

Issues and Facilities. ”

●

●

replace coal and/or fission, affect one’s perception of the urgency of fusion research and

development.

None of the research paths presented in

this chapter call for a crash program to develop fusion. It is very difficult to formulate

a credible scenario of major, irreversible

electricity shortages in the early 21st century

that would require fusion’s development on

a schedule faster than that discussed in chapter 4.

Advantages and Risks of Large-Scale International Collaboration: It appears possible

that large-scale international collaboration

could enable the United States to make progress towards assessing fusion’s potential at

a substantially lower cost than would be required for the United States to proceed independently. Chapter 7 discussed the advantages and risks of large-scale international

collaboration in future fusion projects. Different evaluations of the costs and benefits of

large-scale collaboration, which were presented in chapter 7, affect one’s willingness

to consider undertaking the next stages of

fusion research collaboratively. In addition,

different assessments of the obstacles to international collaboration may affect one’s willingness to negotiate a collaborative agreement.

Implications of the Need for Expensive Research Facilities: Chapter 4 identified several

major research facilities that may be required

to evaluate fusion’s potential. The total worldwide cost of these facilities has been estimated at $6 billion, with a next-generation

engineering test reactor alone expected to

cost well over $1 billion. As long as multibillion-dollar facilities are necessary to assess fusion’s potential, development of fusion power cannot proceed without strong

financial support at the highest levels of

government. The private sector will not be

willing to finance fusion research until fusion’s potential is clearer.

The need for major facilities, along with

the need to conduct a diverse array of supporting research, means that the fusion research program will not make progress towards

evaluating fusion’s energy potential if its

funding is too low. With insufficient fund-
Ch. 8.—Future Paths for the Magnetic Fusion Program ● 191

ing, the program must either delay complete

evaluation of fusion’s potential or await technological developments (which may never

be realized) that lower the cost of the research remaining to be done.

● Near-Term Benefits: Chapter 6 discussed

near-term benefits of fusion research such

as increasing scientific understanding, educating and training skilled technical personnel, and developing technologies with economic and defense applications. Different

values assigned to these benefits, and different estimates of the benefits that would have

been derived had the resources spent on fusion been allocated elsewhere, lead to different levels of emphasis on fusion research.

● Potential for Surprise: In many respects, fusion technology will be unlike any existing

technology, and it may open up capabilities

and applications that cannot be foreseen

today. Like other qualitatively new technologies, fusion’s most significant impacts may

be totally different than those that were expected prior to its introduction. Some observers might oppose fusion’s development

because of this inherent potential for unanticipated consequences; others would eagerly

support exploration of the technology primarily because of the new possibiIities it may

offer. Since unforeseen capabiIities or consequences are by definition impossible to

predict, this report cannot and does not address them.

The possible advantages and disadvantages of

each of the four paths outlined at the beginning

of this chapter are described below, along with

the assumptions that would lead to each’s selection. The discussions of the paths are interdependent; in many cases, the advantages of selecting

one approach also describe the disadvantages of

selecting another. The paths are discussed in general terms, and the detailed structure of the fusion research program is not specified under any

of them. Extensive additional study would be required to determine the best way to implement

each path.

THE INDEPENDENT PATH

Description

The goal of the Independent path would be to

aggressively establish the scientific and technological base necessary to evaluate fusion’s potential and to decide by the early 21st century whether

to proceed with a demonstration reactor. All the

facilities required to establish this base would be

funded and operated domestically under this approach. The exact funding necessary for this path

cannot be determined without detailed additional

examination, but considerably more support

would be required than is currently available to

the fusion program. On average, between $500

million and $1 billion per year probably would

be required over the next 20 years, with peak annual funding possibly exceeding $1 billion. Widespread international cooperation might continue,

but it would fall well short of the shared decisionmaking and funding that would characterize the

Collaborative approach. The Independent path

is similar to the one specified (but not funded)

in the 1980 Magnetic Fusion Energy Engineering

Act. 2

Motivations and Assumptions

Choice of this path would be motivated by the

assumption that evaluating fusion’s potential early

in the next century is an important national goal.

The probability of success and the need for developing fusion would both be assumed high

enough to justify considerably increasing the current U.S. investment in fusion research.

The benefits of conducting fusion research

without depending on the participation of other

countries would be assumed to outweigh the cost

savings and other possible advantages of largescale international collaboration. Although the

~Tht\ act IS described In the section ot ch. 3 titled “The 1980$:

Le\ elln~ Ot’t’ “
192 . Starpower: The U.S. and the International Quest for Fusion Energy

near-term domestic benefits of fusion research

probably also would be highly valued, the prospects of developing a viable energy technology

would be the primary motivation for selecting this

path.

Advantages

Control Over Research and Development.–

Under this approach, the United States would be

fully self-sufficient in acquiring the information

needed to assess fusion’s potential. Decisions

made in other countries or difficulties in largescale international collaboration would not affect

the U.S. ability to evaluate fusion’s potential on

a time scale of its own choosing. Under this approach, the United States could attempt to regain a position of world leadership in fusion research, rather than accept the technological

parity required for true collaboration and interdependence.

If the United States were to go on to make a

positive assessment of fusion’s potential, and if

the U.S. technological capability in the field were

unmatched by other international fusion programs,

the United States would have the advantage of

leading the development and commercialization

of fusion technology.

Energy Supply. —If the United States were to

make a positive evaluation of fusion’s potential

as a result of pursuing this approach and were

then able to develop and commercialize fusion

technology, a new, potentially attractive source

of energy would become available. Even if fusion

were not viewed as preferable to other energy

technologies, investment in the technology might

still be justified since fusion would be available

as a hedge against unforeseen or underestimated

difficulties with other energy sources.

Manpower, Infrastructure, and Technology

Development.–Conducting fusion research independently could have significant domestic benefits, in terms of training personnel, acquiring a

domestic fusion infrastructure, and developing

associated technologies. Since more funds devoted

to the fusion effort would be spent domestically

than under any of the other research approaches,

these domestic benefits would be realized to a

greater extent under this approach. Moreover,

the United States would not be dependent on externally acquired information or technical expertise.

International Stature. –Through this research

approach, the United States would be able to

demonstrate its technological capability and bolster its international stature. In addition to the potential economic returns, being in a position of

world leadership could give the United States significant leverage in future cooperative projects

and couId make the United States a more desirable cooperative partner.

Disadvantages

Cost.–The principal disadvantage of this research approach is its cost, which is considerably higher than that of any other approach. Fusion

is not guaranteed to succeed, and the investment

in fusion research may not “pay off” with an attractive energy technology. In this case, the investment in fusion research might be considered

wasted. Benefits of the fusion program such as

scientific return, training of personnel, technological development, and international stature–

hard as they are to measure–are unlikely to

justify the full cost of independently developing

fusion technology.

Potential Overemphasis.–A sense of urgency

and direction is necessary in order for the fusion

program to command the resources it would require under the Independent path. However, the

risks of program failure are increased if an exaggerated sense of urgency pushes the research effort faster than it can responsibly proceed and

prematurely forces key decisions. A balance must

be struck between proceeding with determination and direction, which is necessary, and rushing into a “crash program, ” which can be counterproductive.

A more subtIe risk could arise if fusion were

emphasized at the expense of improving the existing sources of energy supply, increasing the efficiency of energy use, or developing other energy

supply alternatives. if U.S. long-term energy research concentrates heavily on fusion, the implications of technical or commercial failure could

be serious. Therefore, if concern over energy supply motivates more intense fusion research, it

should also motivate energy research in nonfusion areas.
Ch. 8.—Future Paths for the Magnetic Fusion Program c 193

THE COLLABORATIVE PATH

Description

Ideally, the Collaborative path would accomplish the same technical tasks as the independent path on a similar time scale. However, the

Collaborative path would use the combined resources of the world’s major fusion programs,

making it possible for the individual contribution

of any one program to be smaller than wouId be

needed to perform the same tasks alone.

With large-scale international collaboration, the

U.S. fusion program would require only modest

increases in funding above current levels to evaluate fusion’s feasibiIity early i n the 21st century.

Annual funding on the order of $400 million to

$500 million probably would be necessary over

the next 20 years, with the total being highly dependent on the degree of cost-sharing attainable

through collaboration.

Motivations and Assumptions

Choice of this approach, like the Independent

approach, is based on the assumption that evaluating fusion’s potential in the early 21st century

is an important national goal. The assumed probability of success and the perceived need for fusion power wouId be high, as they would be under the Independent path. The major difference

between this path and the Independent path is

that under this approach the benefits of largescale international collaboration would be assumed

to outweigh the disadvantages. The United States

wouId consider self-determination in fusion either impossible or not worth the price.

Activities under the Collaborative path could

take the form of joint construction and operation

of major facilities, in which several nations’ fusion programs would be simultaneously involved.

Activities could also take the form of allocating

various research tasks to particular programs. If

such an allocation were done, all programs would

eventually need to obtain data (which is rather

easily shared) and expertise or “know-how”

(which is harder to transfer) from the program that

had done a particular piece of research.

The near-term benefits of fusion research would

not be judged important enough u rider this approach to justify conducting all the necessary research domestically. Choice of the ColIaborative

approach assumes that the parties involved wiII

be able to develop a program whose cost and

schedule is acceptable to all, that major experimental facilities can be collaboratively built and

operated, and that equitable allocation of research tasks and results can be arranged.

Advantages

Cost-Sharing.–The principal benefit of the

Collaborative path is the cost-effective utilization

of the resources avaiIable to the major fusion programs worldwide. Total funding now spent annually on fusion research throughout the world

is comparable, or greater than, the amount needed

per year to evaluate fusion’s potential by the early

21st century. If the major fusion programs can

minimize duplication of effort, reaching that evaluation should not require substantial budgetary increases in any of the major programs. Whereas

pursuit of the Independent path requires doubling or tripling annual U.S. fusion budgets, the

Collaborative path may only require funding increases of 20 to 50 percent above current levels.

Energy Supply.– If successfully implemented,

the Collaborative approach would permit the

United States and the other major fusion programs to evaluate fusion’s potential by the early

21st century. The timing of this evaluation is

similar—although possibly somewhat delayed—

from that in the Independent path. However, the

results of a Collaborative research effort would

be more effectively shared among the major fusion programs.

Improving the Technical Base.—Fusion research may proceed more effectively if the research efforts of the major programs are integrated

to a greater degree. All of the major programs

have technical capabilities and skilled personnel

that can contribute to the research and development effort. In addition, effective planning among

the major fusion research programs can ensure

that more research approaches are investigated.

Ifr through such efforts, research efforts can be

mutualIy supportive rather than duplicative, this

widened technological base will benefit fusion

research worldwide.
194 ● Starpower: The U.S. and the International Quest for Fusion Energy

Foreign Policy Benefits.–The United States

may wish to participate in a large-scale collaborative project for diplomatic reasons as well as technical ones. Since there appear to be significant

technical and financial benefits to the United

States from successful collaboration in fusion,

diplomatic motivations would not appear to be

in opposition to programmatic ones.

Disadvantages

Shared Control and Loss of Flexibility.–Under

the Collaborative approach, the United States

would sacrifice some control over the research

program. International collaboration on the scale

necessary for this approach will require compromise by all partners. In particular, some major experimental facilities, such as the international Experimental Thermonuclear Reactor,

wouId probably not be sited in the United States.

This approach could be less flexible than the

others, since decisions—which would be made

multilaterally—would be difficult to modify.

Moreover, depending on how time-consuming

the negotiation process is, the Collaborative path

could take longer than the Independent path to

develop fusion.

Obstacles to Large-Scale Collaboration.–If the

potential obstacles to large-scale collaboration described in chapter 7 prove insurmountable, the

Collaborative approach would fail. In this case,

the United States would either have to make

more resources available for fusion research,

changing to the Independent path, or extend the

schedule for fusion development as discussed in

the Limited path (below).

Cost.–Although the cost of this approach is

substantially less than that of proceeding independently, increases in U.S. annual fusion funding are nevertheless required to carry out this approach. If fusion research does not lead to an

attractive energy source, this investment might

be considered wasted.

Adverse Impact on Domestic Development.–

The Collaborative approach is motivated in part

by pressures to share costs and lessen research

expenditures. However, if international collaboration is supported at the expense of maintaining a healthy domestic program, both the collaborative projects and the domestic program

could be damaged. A viable domestic program

is required to contribute to and be attractive for

future collaboration.

The Collaborative approach may create tension

between undertaking domestic activities, on the

one hand, and participating in joint research with

foreign programs, on the other. Incentives to minimize costs and avoid duplication will have to be

balanced against developing and maintaining

sufficient domestic expertise to contribute to and

assimilate the results of collaborative projects.

THE LIMITED PATH

Description Because there are so many different motivaUnder the Limited path, fusion research would

continue but would not be supported at the level

necessary to evaluate fusion’s potential domestically in the early 21st century. The schedule for

developing fusion under this approach therefore

would be delayed compared with the independent or the Collaborative approaches. With the

Limited path, funding levels would not be sufficient to support a healthy base program simultaneously with the construction of major facilities

tions for pursuing this approach, no single plan,

strategy, or estimated funding level can adequately describe it. Clearly, the funding level

would be less than that needed for the independent path and more than that for the Moth balled

path (below). It probably would be less than that

needed for the Collaborative path, although even

a funding profile sufficient for the Collaborative

path would result in the Limited path if collaboration were found to be undesirable or unworkable.

required’ to make progress in critical research The Limited approach would attempt to retain

areas. a base program in fusion research at universities
Ch. 8.—Future Paths for the Magnetic Fusion Program ● 195

and national laboratories. The program would be

limited to scientific research, however, with funding levels and/or program intent not enabling it

to advance to engineering development and

demonstration. With the Limited path, fusion’s

scientific feasibility probably could be determined. It is unlikely, however, that engineering

feasibility could be determined domestically, and

commercial feasibility would be impossible to

evaluate without increased financial support.

Motivations and Assumptions

With the Limited path, pursuit of fusion would

not be a high national priority. Many different assumptions could result in a lower priority for fusion research and lead to selection of the Limited

path. The Limited path also might be pursued as

a “second choice” if either the Independent or

the Collaborative approaches could not be sustained.

Assumptions that might lead to selection of the

Limited approach include the judgment that fusion’s promise or urgency was not high enough

to justify the Independent approach but too high

to warrant shutting the research program down

entirely. Moreover, either the prospects or the

rewards of international collaboration could be

judged too low to pursue the Collaborative approach.

Perhaps the construction of large experimental

facilities would not be seen as warranted unless

or until further technological development—in or

outside of the fusion program—brought down

costs. Alternatively, it might be decided that while

the near-term benefits of fusion research justified

maintaining a limited program, the energy benefits did not justify a more extensive research effort. Delaying development of fusion’s energy potential need not necessarily reduce the scientific,

educational, and technological benefits of fusion

research.

Advantages

Cost.–The major benefit of the Limited path

is that the United States could maintain a limited

research capability while still retaining the ability to accelerate fusion research at a later time.

It would be cheaper–and therefore politically

easier—to fund a Limited path program than the

higher cost Independent or Collaborative approaches.

Flexibility.–In some ways, research with the

Limited path may be more flexible than with either the Independent or Collaborative paths. Early

design selections for large and expensive research

facilities that would tend to lock in a given line

of research emphasis would be avoided. Delaying these investments could make it possible to

build them either at substantially lower cost or

with a higher probability of commercial success.

Risk Avoidance.–Under this approach, the

United States could let the rest of the world shoulder the expense and take the risk of determining fusion’s feasibility. The United States would

retain a base program in fusion research to preserve the expertise needed to evaluate and eventually reproduce work done abroad. The United

States, of course, would start out with a competitive disadvantage in this case and might or might

not be able to catch up. However, it would also

be able to evaluate whether or not the technology was attractive without the substantial investments required to pursue the Independent or Collaborative paths. The United States would be free

to attempt to develop an improved technology

at some later time.

Disadvantages

Delaying Energy Supply .–The fundamental

disadvantage of the Limited path is that it delays

the evaluation of fusion. At our current level of

understanding, experimental devices that are inherently large and expensive are required to resolve key uncertainties in the development of fusion power. Unless these facilities are funded,

progress cannot be made and fusion’s potential

cannot be determined or developed,

Technical developments may ultimately decrease the cost or eliminate the need for expensive experiments. However, it is not likely that

such developments will occur quickly enough for

the Limited approach to make fusion power available on the same schedule as the Independent

or Collaborative approaches. Moreover, signifi-
196 ● Starpower: The U.S. and the International Quest for Fusion Energy

cant developments may be less likely to occur

or be recognized in the absence of a more ambitious research program.

Loss of Direction and Scope.—If the fusion research program is not targeted towards an evaluation of fusion’s prospects as an energy source,

it might become more of a basic science/plasma

physics research program than an energy program. Without the direction provided by a relatively near-term goal—evaluating fusion’s engineering feasibility—the program’s subsequent

evolution might lead it away from those issues

that must be resolved to develop fusion reactors.

This drift would not only delay the development

of fusion power but might also make its eventual

development less likely.

Damage to Fusion Infrastructure.–Lim ited

Federal funding of fusion research could adversely

affect many participants in the fusion research

program. Industrial participation would be the

most severely constrained; steady and predictable funding is required for industry to develop

and maintain the capability to participate in fusion research. Depending on the funding level,

national laboratories and universities might also

have to cut back on fusion work.

Moreover, the field of fusion research in general and university programs in particular might

not be able to attract the most talented students

if the program were perceived as having an uncertain future, In this event, a valuable source of

new ideas and innovation would be lost.

Loss of Momentum and International Stature.–

With the Limited path, the fusion program could

lose its momentum. Unless other countries also

limited their programs, the United States would

fall behind. If other countries successfully commercialized fusion technology, the United States

could be at a competitive disadvantage, at least

initially.

However, U.S. decisions and foreign decisions

are not independent. Given that fusion research

budgets are set in all the major fusion programs

through a political process that balances fusion

against other priorities, U.S. action to lower the

priority of fusion research might weaken the positions of fusion researchers in other programs.

Foreign fusion programs might reduce their research efforts. However, the other world fusion

programs are clearly developing fusion for broader

reasons than simply keeping up with the United

States, and none of them are likely to eliminate

their programs.

Difficulty in Collaboration.– If foreign fusion

programs pursue research more aggressively than

the United States, the United States may no

longer be seen as a desirable collaborative

partner.

THE MOTHBALLED PATH

Description energy supply technologies, to see whether the

decision to stop funding fusion research should

With the Moth balled path, the magnetic fusion be reviewed.

research program would shut down. To capitalize on the research investment to date, this path In practice, however, monitoring might be difwould ideally be implemented in a manner that ficult. Competing funding priorities, too, might

preserved the existing state of knowledge in the make it hard to acquire the resources needed to

field and eased the transition of people and fa- reevaluate a canceled program.

ciIities from fusion to other areas. To keep open

the option of restarting the fusion program in the Motivations and Assumptions

future, some resources would be desirable (either provided directly or through other programs) Choosing the mothballed approach implies that

to permit periodic reevaluation of fusion. Tech- development of fusion–even as a hedge–does

nical developments in other fields would have not merit appreciable investment now or in the

to be monitored, along with progress in alternate near future. Proponents of this approach might
Ch. 8.—Future Paths for the Magnetic Fusion Program ● 197

consider the current state of fusion technology

analogous to that of computer technology in the

19th century: although many of the fundamental concepts were known, a century of technological progress in widely disparate fields was

required before computers of any practical significance could be built.

Technological pessimism is not likely to be the

deciding factor in stopping the fusion program,

since the operation of ClT—if successful—should

confirm the scientific feasibility of fusion. instead,

the decision to cancel the program probably

wouId be motivated by the belief that fusion research will not result in a commercially, socially,

or environmentally attractive source of energy,

or that finding out how useful fusion could be

is too expensive. The near-term benefits of conducting fusion research would not be assumed

to justify the program, and the expected payoff

of fusion would be considered too low to make

cost-sharing with other countries attractive.

Advantages

Saving Money .–The major advantage of this

approach would be avoiding the costs of future

fusion research.

Disadvantages

Unavailability of Possible Energy Supply.–

The major risk of this approach is that fusion’s

potential as an energy source would not be realized. ShouId future circumstances make reevaluating fusion desirable, restarting the program

wouId be expensive, difficuIt, and time-consuming.

Destruction of Fusion Infrastructure.–With

the Moth balled path, the people and facilities that

currently carry out fusion research would switch

to other programs; the associated benefits of fusion research such as personnel training, scientific research, and technological development

would not continue in their current form, Although scientific data and technological accomplishments would not be lost, the “know-how”

of individual researchers would be. Decades would

be required from whenever a decision were

made to resume the program until the earliest

time that it could lead to a usable product. Dismantling the existing technological base and personnel pool does not irrevocably eliminate fusion

as an option, but significant costs (in both time

and resources) would be required to rebuild fusion research capability.

Mitigating this disadvantage somewhat is the

breadth of plasma physics as a research discipline.

Since plasma physics is intrinsic to many applications outside of fusion, plasma physics research

and application would certainly persist through

non-fusion-program sources, even if fusion research were discontinued. Although the areas of

plasma physics most relevant to fusion would suffer, general plasma physics research could provide a core of expertise if a program restart were

required.

Inhibiting Technical Development.–Without

an extensive base of technical personnel trained

in and sensitive to problems relevant to fusion,

discoveries that might make fusion easier to

achieve could go unrecognized.

Elimination of International Stature in Fusion.–

if it is not conducting domestic fusion research,

the United States will be unable to collaborate

with other countries or benefit from the results

of research done abroad. If fusion technology

were developed successfully abroad, it could take

many years for the United States to reproduce

the technology.
Appendixes
Appendix A

Non-Electric Applications of Fusion1

The baseline D-T fusion reactor discussed in chapters 4 and 5 produces energetic neutrons as its immediate output. In an electric generating station, the

energy of these neutrons would be recovered as heat

and used to generate electricity. Other possible applications of D-T fusion technology might use the neutrons themselves to produce fission or fusion fuels or

to induce nuclear reactions that change one isotope

or material into another. Applications of fusion as a

neutron source and other non-electric applications of

fusion energy are discussed below.

Fusion as a Neutron Source

Each D-T reaction in the plasma produces one neutron, which is needed to breed tritium to replace that

used in the reaction. However, additional neutrons

can be generated by neutron multipliers i n the reactor

blanket. 2 These “excess neutrons” are available to

make up for losses as well as for other purposes, such

as the production of materials in the reactor blanket.

Therefore, fusion reactors could be used as neutron

sources in addition to sources of electricity.

If it produced a sufficiently valuable product, a fusion neutron source would not need to generate net

electric power to be cost-effective. In practice, however, few if any such products exist; system studies

show that a fusion reactor serving as a neutron source

will probably also need to produce electric power to

be economically viable. (A possible exception, tritium

production, is discussed below.)

Fusion-reactor neutron sources could have significant advantages over fission reactors, the major existing large-scale sources of neutrons. A suitably designed fusion reactor would generate only about

one-sixth the heat of a fission reactor with the same

neutron output. Furthermore, the energy of the fusion

neutrons is several times higher than the energy of fission neutrons, thus permitting applications that are not

possible with fission.

Tritium Production

One application of a fusion-reactor neutron source

would be production of tritium beyond that needed

to fuel the fusion reactor.3 As discussed in chapter

4, tritium self-sufficiency is a key issue for a fusion electric power reactor;4 it is especially difficuIt to design

a power-producing reactor capable of producing substantial amounts of excess tritium. However, tritium

production can be enhanced at the expense of electricity generation.

Tritium has several industrial, medical, and military

applications; its largest user is the nuclear weapons

program. Tritium is radioactive, with 5.5 percent of

the tritium stockpile decaying each year. Therefore,

the tritium supply for nuclear weapons requires constant replenishment even if no additional weapons are

built. Four fission reactors are operated for the Department of Energy (DOE) in Savannah River, South

Carolina, to produce tritium for nuclear weapons.

These reactors are currently about 35 years old, and

they will soon need replacement.

A recent National Research Council study found that

although fusion reactors have promising features for

breeding tritium, fusion technology is not yet sufficiently advanced to expand or replace the Savannah

River facilities.5 The engineering development and

testing needed to create reliable fusion tritium-breeders

cannot be completed by the time decisions must be

made concerning the Savannah River reactors. Nevertheless, the study also concluded that fusion has potential for producing tritium, and that DOE should

“undertake a program that analyzes and periodically

reassesses the concept, including design studies, experimentation, and evaluation, as fusion development

proceeds.” 6

Fusion technology could be applied to tritium production without necessarily altering the technical

course of the civilian magnetic fusion research program. However, if use of fusion technology for tritium

production were to precede its commercial application as a civilian electricity generating technology, the

fusion research program nevertheless could be proT Much ot the material In this appendix is drawn from K. R, Schultz, B,A,

Engholm R F Bourque, ET Cheng, M j, Schatfert dnd C. P,C, L%’ong, The

Fusion ApplIc atwrrs and Market El .jluatlon - “FAME’ ’-. Study, bv GA Technologies, In{ San Diego, CA, 1986 This study was done under contract

to the Department of Energy’s (Iflce of Fusion Energy

2Neutron multipliers are discussed In ch 4, box 4-B

‘Tntlum-produc i ng fusion breeders are dlscuiw>d I n N atI{Jn,I I Rt,w,l r{ h

Council, Committee on Fusion Hybrid Reactors out/ooA for thf, Fuworr }{L

brd and Trltlurn-Breeding Fusion Reactors (Washington D( N,l:l~)nal ,Ac ,IC{-

emy Press, 1987), pp. 94-110. See the following wctlon ot t h I\ al~~wndlx for

detlnltlons and discussion ot’ (usIon hybrid reactors,

‘See the section “The Fusion Blanket and Flr~t \\’all’ In c h .I

5Natlona I Research L-ou ncl 1, Out/ooA for (Iw Fuwon H},hrd ,]ncf Tritlurm

Breeding Fusion Reactor,, op clt , p 16.

61bld

201
202 ● Starpower: The U.S. and the International Quest for Fusion Energy

foundly affected. On one hand, the nuclear weapons

program would shoulder some of the development

costs and would provide a near-term motivation for

supporting fusion research. Furthermore, associating

fusion R&D with the nuclear weapons program would

ensure it a higher national priority.

On the other hand, associating fusion power with

the nuclear weapons program could also become a

severe liability in terms of public acceptance. Moreover, since the technical requirements for breeding

tritium and producing electricity are different, features

of the tritium-breeder design would not necessarily

be applicable in an electric power reactor. The institutional experience gained in developing, building, and

operating a military tritium-breeder may be even less

transferable to a civilian power reactor than the technical experience because, at present, regulatory mechanisms for the two are so different.7 For all of these

reasons, adopting the technological or institutional

framework from a military tritium-breeder to the civilian fusion program could seriously compromise the

future acceptability of fusion power.

Fissionable Fuel Production or Use

In a fission/fusion hybrid reactor, excess fusion neutrons are used to breed fissionable fuel or to induce

fission reactions within the fusion reactor blanket.

There are, correspondingly, two different types of fission/fusion hybrid: one that uses fission reactions in

its blanket to multiply the energy generated in the fusion core, and one that suppresses blanket fission reactions to generate fissionable fuel for use i n pure fission reactors. The former type, the “power-only”

hybrid, does not produce fissionable fuel. The latter,

or “fission-suppressed” hybrid, does not produce

much of its own power from fission reactions; instead,

it transforms “fertile” materials that are not readily fissionable into fissionable fuels such as uranium or

plutonium. In both types of hybrid, the total energy

released (or made available) is much larger than that

available from fusion reactions alone. g

Since most of the energy generated in a power-only

hybrid is due to fission reactions, the amount of fusion power generated by such a device need not be

large. Therefore, the fusion core of a power-only hy-

~Weapons-related DOE facilities are not now sub)ect to the same process

ot Nucledr Regulatory Comm!sslon and Natlona[ Envlronmenta[ Poi Icy Act

review that governs civilian nuclear facl I itles. However, publ IC pressure tor

Increasing the regulation of mtlltary reactors IS growing.

aEnergy multiplication occurs because a fission reaction releases about 10

times as much energy as a fusion reaction. Each excess neutron that Induces

a tlsslon reaction in the blanket releases many times more energy than It

originally carries. (The same energy multlpllcatlon occurs when flsstonable

material produced In a tuslon reactor IS removed to fuel external reactors,

except that the addltiona I energy IS released In the cxterna 1 reactors and not

In the fusion blanket. )

brid would not need to achieve as high a level of performance as the core of a pure fusion power reactor

in terms of parameters such as energy gain. g

In combining the fusion process with fission, a hybrid reactor could also combine their liabilities. Since

hybrid reactors involve the production and/or use of

fissionable fuels, their environmental, safety, and

proliferation concerns are more serious than those of

pure fusion reactors; many of the environmental and

safety concerns of nuclear fission, both perceived and

actual, could be transferred to the hybrid. Furthermore, a complete evaluation of the fuel-producing hybrid must include the client fission reactors. If the incentive for pursuing fusion research is to provide an

energy alternative that is environmentally or socially

preferable to nuclear fission, then combining fusion

with fission in a fission/fusion hybrid reactor might

not accomplish that goal.

The economic justification for hybrid reactors is

weak at present because the price of uranium fuel is

so low. According to the National Research Council

hybrid study, uranium prices must rise by a factor of

between 6 and 20 for a fission/fusion hybrid to be economically attractive.l ” The study concluded that accelerated use of fission reactors in the United States,

coupled with policy decisions requiring U.S. reactors

to be fueled with domestic uranium supplies, could

increase the domestic price of uranium by a factor of

10 by the year 2020. However, a more likely rate of

fission growth would cause prices to reach this level

sometime between 2020 and 2045, and relaxing the

constraint on domestic supply would delay such a

price increase for an additional 30 years. Therefore,

the NRC study concluded that fission/fusion hybrids

will probably not be economically justified in terms

of increased uranium price before the middle of the

next century.

Several additional factors besides the price of uranium affect the economic viabiIity of fission/fusion

breeders. First, advanced-converter fission reactors

that use uranium much more efficiently than present

light-water reactors would be less sensitive than present reactors to the price of uranium. Development of

these more efficient reactors would further delay the

time when breeders would become attractive. Second, any discussion of hybrid breeders must compare

them to pure fission breeders, which can also produce

fissionable fuel. Such a comparison is beyond the

scope of this study.

9Energy gain IS discussed I n the section of ch. 4 titled ‘‘Sclentklc Progress. ’

1~Natlonal Research COU ncil, Out/ook fOf t/7e ~usfon HyLmd and TrmumBreedlng Fumm Reactors, op. cit., p 8, The study esttmated fission/fusion

breeders to become economically viable when the price of uranium oxide

re~che> trom $100 to $300 per pound; the price currently 15$17 per pound
App. A—Non-Electric Applications of Fusion ● 203

Other Isotope Production

With the possible exception of tritium and fissionable fuels, no materials have yet been identified that

would justify building a fusion reactor for the sole

purpose of producing them. To be economically

worthwhile, high-value materials would have to be

produced from inexpensive ones through reactions

with fusion neutrons. In addition, extraction of the

desired isotope from the fusion blanket could not be

too expensive. Furthermore, the amount of the material produced in a fusion reactor must not be so large

compared to the demand that it would saturate the

market { driving down the price and destroying the

value of the material.

it would be much easier to justify producing special materials or isotopes in a fusion reactor if electricity were produced at the same time. A recent study

has identified cobalt-60 (60Co) as an isotope that might

be economically produced in a fusion electric generating station.11 However, demand for 60Co would have

to be much greater than it is now for this process to

be viable, since the amount of 60Co that could be produced annually in a single fusion reactor is much

larger than the present annual demand.

Cobalt-60 is an intensely radioactive material whose

primary use is in sterilizing medical products, with secondary uses in providing cancer radiation therapy and

food preservation via irradiation. Food preservation,

in particuIar, couId be a rapidly growing application.

Furthermore, 60Co also could be used to treat sewage

by sterilizing it, although this application has yet to

be commercialized. It is possible, therefore, that 60Co

demand might increase substantially.12

The worldwide demand for replenishing existing

60C0 stocks is currently estimated to be about 11

megacuries per year, 13 most of which is produced by

Atomic Energy of Canada, Ltd. in the heavy-water

moderated CANDU reactors operated by Ontario

Hydro. A commercial fusion power reactor could produce hundreds of megacuries of 60Co per year with

a blanket optimized for 60Co production. Therefore,

this application is viable only at greatly increased demand levels; depending on its increased use for food

I I B A, Engholm, E,T, Cheng, and K R, Schultz, ‘‘Radlolsotope Produc-tlon

In Fusion Reactors, ” GA Technologies Inc. San Diego, CA (undated) Thl~

article was prepared as part ot’ the “Fusion Appllcatlonf Studv” by K.R

Schultz, et al., 1986.

lzlbld., p, 2.

I lone Curie of any radioactive substance IS the amount that procluce~ ~ ~

X 101~ radloactl~e dtslntegratlons per second: 1 rnegacurle IS 1 mllllon ( urle~

One curie ot pure ‘co would have a mass ot 0.88 mllllgram, and 11 rnegac w

rles w ou Id have ~ mas; of 9 7 kl Iograms (2 1 pou rids) (Actual ‘{ICO \ou rce~

do not consist ot pure bOCo In practice, less than 10 percent of the cobalt

I n a boCo source consists of the b(]Co Isotope I I n 1984, the prlc e ot ‘IqCO w a~

about !$ 1 00 per cu rle (Ibid , pp. 2-3 I

preservation, the annual growth in this demand over

the next several years has been estimated at 6 to 25

percent.14

Radioactive (Fission) Waste Processing

In theory, the neutrons from a fusion reactor could

be used to change radioactive fission wastes into

shorter lived materials that would decay more quickly,

posing less long-term hazard. However, several studies

in the 1970s analyzed fusion’s capabilities to process radioactive waste from fission reactors, and the

results were not promising.15 These studies determined that extremely high levels of fusion reactor performance and decades of neutron irradiation would

be required, along with advanced isotope and chemical separation processes. Even if these requirements

were met, it was unclear whether this approach offered a net advantage over waste burial. The benefit

of reducing the long-term hazard associated with fission wastes would have to be balanced against the

technological difficulties associated with transforming

them, as well as the short-term risk of releasing these

wastes i n an accident at the processing faciIity.

Other Possible Nonelectric

Applications of Fusion

Synthetic Fuels

Currently, about two-thirds of all energy used in the

United States is consumed directly by users in the form

of fossiI fuel; only one-third is used to generate electricity, Although the trend in future energy use is

towards increasing electrification, many requirements

for non-electric sources of energy such as liquid or

gas fuels will likely remain.

It may be possible to take advantage of the high temperatures present in fusion reactors, along with the

electricity generated by them, to generate hydrogen

gas by decomposing water into hydrogen and oxygen.

Hydrogen has applications either directly as a fuel or

in the synthesis of liquid fuels. The GA fusion applications study indicated that fusion might be an economically competitive source of hydrogen i n the long

term but did not demonstrate a clear advantage over

high-temperature fission-based sources of hydrogen

that could also be available by the time fusion is commercialized.

I ~1 bid. , p 3

) ‘For a rei icui ot thwe stuciles ~ee Schultz, et al , Fusion 4pp/IcaIIon\ S(ud)

Op Cit. pp Y-1 o
204 ● Starpower: The U.S. and the International Quest for Fusion Energy

Process Heat

Another energy requirement currently satisfied by

non-electric sources of energy is process heat. Process heat is less transportable than electricity; it must

be used at locations close to the generating site. Moreover, although there are many users of process heat,

few require more than a few hundred megawatts

each. Essentially all of these users now use fossil fuels.

Present fusion reactor designs would produce on the

order of 3,000 megawatts of heat (corresponding to

1,000 to 1,200 megawatts of electricity at 35- to 40-

percent conversion efficiency), and there would be

little motivation to construct such a fusion plant dedicated solely to the production of process heat. There

does not even appear to be significant economic advantage associated with recovering waste heat produced as a byproduct of electricity generation. Process heat does not appear to be an attractive use for

fusion reactors as long as fossil fuels are available.

This conclusion is supported by present-day experience with nuclear fission powerplants, which are not

used for process heat production in the United States.

In the far future, if fossil fuels become too expensive

or too difficult to use in an environmentally sound

manner, fusion could become attractive as a source

of process heat due to lack of an alternative.
Appendix B

Other Approaches to Fusion

The main body of this report has discussed magnetic

confinement fusion, the approach to controlled fusion

that the worldwide programs emphasize most heavily. However, two other approaches to fusion are also

being investigated. All three approaches are based on

the same fundamental physical process, in which the

nuclei of light isotopes, typically deuterium and tritium, release energy by fusing together to form heavier isotopes. Some of the technical issues are similar

among all the fusion approaches, such as mechanisms

for recovering energy and breeding tritium fuel. However, compared to magnetic confinement, the two approaches discussed below create the conditions necessary for fusion to occur in very different ways, and

some substantially different science and technology

issues emerge in each case.

Inertial Confinement Fusion1

The inertial confinement approach to fusion research

has been studied for some two decades, and its current budget almost half that of the magnetic confinement program. In inertial confinement fusion, a pellet of fusion fuel is compressed to a density many times

that of lead, and then heated and converted to plasma,

by bombarding it with laser or particle beams (see figure B-1 ). At this density, about 10 billion times the density of a magneticalIy confined plasma, the confinement time needed is so small (less than one-billionth

of a second) that it shouId be possible to generate net

fusion power before the pellet blows itself apart. The

pellet’s own inertia is sufficient to hold it together long

enough to generate fusion power,

Inertial confinement already has been demonstrated

on a very large scale in the hydrogen bomb, an inertially confined fusion reaction whose input energy is

provided by a fission (atomic) weapon. The challenge

of laboratory-scale inertial confinement research is to

reproduce this process on a much smaller scale, with

a source of input energy other than a nuclear weapon.

In a hypothetical inertial confinement reactor, microexplosions with explosive yields equivalent to about

one-tenth of a ton of TNT would be generated by irradiating fusion pellets—called targets—with laser or

particle beams; these explosions would be repeated

several times a second.

‘The U S inertial con flnem[~nf tuilon rewarch program I\ rm Ie\\ ed I n ,]

recent report by the Nat Ion,l I Rew,] rc h LOU nc I I Ret ~e~t of rhe Dep.] rfment

of f m’rqi s /neflI,I/ Conflnemenf Fu\lon Progr,]rn {Wf,]sh I ngton, DC Nattona I

A( .I(l(>rm}, l)rf>~i I W() I

The issues addressed by inertial confinement fusion

research in the United States concern the individual

targets containing the fusion fuel; the input energy

sources, called drivers, that heat and compress these

targets; and the mechanism by which energy from the

driver is delivered–or coupled–into the target. Due

to the close relationship between inertial confinement

fusion target design and thermonuclear weapon design, inertial confinement fusion research is funded

by the nuclear weapons activities portion of the Department of Energy’s (DOE’s) budget. Inertial confinement research is conducted largely at nuclear weapons laboratories; its near-term goals are dedicated

largely to military, rather than energy applications, and

a substantial portion of this research is classified.

There are two near-term military applications of inertial confinement fusion—one actual and one not yet

realized. First, because the physical processes in a pellet micro-detonation resemble those in a nuclear

weapon, inertial confinement experiments now contribute to validating computer models of these processes, to collecting fundamental data on the behavior

of materials in nuclear weapons, and to developing

diagnostic instruments for actual nuclear weapons

tests. These activities can be conducted today with existing high-energy inertial confinement drivers.

These applications could be greatly intensified, and

a second set of applications would arise, if a laboratory facility producing substantial pulses of inertially

confined fusion energy could be developed. No such

facility yet exists. Such a facility could simulate the

effects, particularly the radiation effects, of nuclear

detonations on systems and components. This application might be particularly important if a Comprehensive Test Ban Treaty prohibited underground tests

of nuclear weapons.

The near-term, military inertial confinement research

effort also contributes information that would be essential to any longer term commercial applications.

For example, both military and civilian applications

of inertial confinement fusion (other than the computer program and diagnostic development activities

that are being conducted today) require that an inertial confinement target generate several times more

energy than is input to it. Such an accomplishment,

which would show the scientific feasibility of inertial

fusion, is beyond the capability of any existing laboratory device. (Of course, thermonuclear weapons

have already demonstrated the scientific feasibility of

very-large-scale inertial confinement fusion. )

205
206 . Starpower: The U.S. and the International Quest for Fusion Energy

Heating

Laser or particle beams

rapidly heat the surface

of the fusion target,

forming a plasma

envelope.

Figure B-1.— Inertial Confinement Fusion Process

Compression

Fuel IS compressed by

rocket-like blowoff of

the surface material

Ignition

The fuel core reaches

high density and ignites.

Burn

Thermonuclear

burn spreads

rapidly through the

compressed fuel. yielding

many times the

input energy.

SOURCE Lawrence Livermore National Laboratory, “ICF Reaction, ” Energy and Technology Review, April-May 1986

The technical requirements for commercial applications of inertial confinement fusion go considerably

beyond the requirements for weapons effect simulation and would require still further scientific and technological development. Due to the relatively low efficiencies (e.g., 10 to 25 percent) at which the drivers

operate, each target explosion must generate several

times more energy than it is driven with to reach

breakeven. An additional factor of 4 to 10 is required

beyond breakeven to produce substantial net output.

In a commercial reactor, therefore, as much as 100

times as much energy must be released in a pellet explosion as is required to heat and compress the pellet

to the point where it can react. Furthermore, commercial energy production requires that pellets be detonated several times a second, far more frequently than

needed for military applications. Finally, cost-effectiveness, reliabiIity, and high efficiency are much more

important for energy applications than miIitary ones;

successful commercialization will depend on how

well the technology addresses the commercial requirements discussed in chapter 5.

A significant potential advantage of inertial confinement over magnetic confinement is that the complex

and expensive driver system can be located some distance away from the reaction chamber. Because radiation, neutron-induced activation, and thermal stress

due to the microexplosions could be largely confined

to the reaction chamber, the driver would not have

to be designed to withstand this environment. In the

core of a magnetic confinement fusion reactor, on the

other hand, systems both for supporting and maintaining the plasma and for recovering the energy and

breeding tritium fuel are located in high radiation, high

neutron-flux environments. A second potential advantage of inertial confinement arises from the relatively

relaxed vacuum requirements inside the reaction

chamber, which would permit the use of neutron absorbing materials such as liquid lithium inside the first

structural wall of the reactor. Use of such neutron absorbers would lessen neutron irradiation levels in the

reactor’s structural elements, increase the lifetimes of

those elements, and lessen induced radioactivity

levels.

On the other hand, inertial confinement also has

disadvantages compared to magnetic confinement. inertial confinement is inherently pulsed; the systems

needed to recover energy and breed fuel in the reaction chamber have to withstand explosions equivalent to a few hundred pounds of TNT several times

a second. Inertial confinement reactors must focus

high-power driver beams precisely on target in this

environment. Furthermore, the energy gains needed

for these facilities must be much larger than those of

a magnetic confinement device to make up for driver

inefficiencies.
App. B—Other Approaches to Fusion . 207

Four principal driver candidates are now being studied in the U.S. inertial confinement research program.

Two of them —solid-state or glass lasers and light-ion2

accelerators—have by far the largest facilities; the

other two principal candidates—gas lasers and heavy

ion accelerators—are in lesser stages of development.

Major U.S. glass lasers are located at Lawrence Livermore National Laboratory in California and the University of Rochester Laboratory for Laser Energetic in

New York. The Livermore facility, the most powerful

laser in the world, does both classified and unclassified inertial confinement research; the University of

Rochester facility conducts only unclassified research

on a laser fusion approach that is not as relevant to

weapons applications as is the approach pursued at

Livermore. The largest light-ion accelerator in the

world is located at Sandia National Laboratory in New

Mexico; like the Livermore facility, it conducts both

unclassified and classified research. The krypton-fluoride gas laser, the third driver candidate being studied, is being developed at Los Alamos National Laboratory. Other contributors to the laser and light-ion

inertial confinement programs are the Naval Research

Laboratory and KMS Fusion, Inc., the only private corporation significantly involved.

A fourth driver candidate—the heavy-ion accelerator

—is much less developed than the laser or light-ion

drivers. Unlike light-ion and laser research, heavy-ion

accelerator research is a non-military program funded

by the Office of Energy Research, the same DOE office that funds the magnetic confinement fusion program. 3 Heavy-ion experimental work is limited to accelerator technology, and in the United States it is

concentrated at Lawrence Berkeley Laboratory in California.

Other national fusion programs conduct inertial

confinement research, but at a significantly lower level

of effort than their magnetic fusion programs. International collaboration is much more restricted in inertial fusion than it is in magnetic fusion due to U.S.

national security constraints. On balance, the inertial confinement program involves scientific and

technological issues that are quite distinct from those

relevant to magnetic fusion. A detailed comparison

of the relative status and prospects of inertial confinement and magnetic confinement fusion is beyond the scope of this assessment.

2Llght Ions are Ions of IIght elementj such as Ilthlum

‘The heav}-lorl research program IS f,] r smal Ier than the magnetic contl nement program and IS managed by a dltterent pafl ot the D(>E Offlce of Energy

Research

Cold Fusion

Another approach to fusion, presently at an embryonic stage of development, is fundamentally different from either the magnetic or inertial confinement

concepts. This approach, called ‘‘cold fusion” or

“muon-catalyzed fusion, ” might make it possible to

bypass the requirement for extremely high temperatures that make the magnetic and inertial approaches

so difficult.4

If it were possible to “shield” the electric charge

of one of the nuclei in a fusion reaction, one nucleus

could get very close to another nucleus without being repelled. In this case, fusion reactions could occur at far lower temperatures than wouId otherwise

be required, since the extreme temperatures needed

to overcome the mutual repulsion of two electrically

charged nuclei would be unnecessary. Such shielding can in fact be provided by a subatomic particle

called the muon. The muon—like the electron—has

a charge that cancels out the charge of a hydrogen

nucleus. But unlike the electron, the muon binds so

tightly to the nucleus that the nuclear charge is shielded

even down to the distances where fusion reactions can

take place. Therefore, once a muon becomes bound

to a nucleus, the combination can approach a second nucleus closely enough to fuse without the need

for extreme temperature.

If the muon is freed in the subsequent fusion reaction, it can become captured by another hydrogen

nucleus to repeat the process. I n this way it serves as

a catalyst, enabling fusion energy to be released without itself being consumed. However, since the muon

is unstable, muon catalysis can be practical only if

each muon generates more than enough energy during its 2.2-microsecond Iifetime to make its own replacement.

Muon-catalyzed fusion reactions were actually observed in high-energy physics experiments in the

1950s. However, the muons were rarely observed to

induce more than one fusion reaction each before

decaying, compared to the hundreds of reactions per

muon that would be necessary to make the process

worthwhile. More recent experimental and theoretical work has shown that the number of fusion reactions

that can be catalyzed by a single muon depends on

parameters such as the density and temperature of the

deuterium-tritium mixture into which the muon is injected. Experiments have shown that muons are capable of catalyzing many more reactions during their

lifetime than had been thought many years ago.

4A d Iscusston of recent muon -cata lyzeci tuslon rewarc h IS gI\ en I n ‘C-dd

Nuclear Fusion, ” by Johann Ratelskl ~nd Ste\ en E Ionw In the july I ’18-

Is+ue ot Sclerrt(fjc Arnerlcan pp 84-8 9
208 ● Starpower: The U.S. and the International Quest for Fusion Energy

Whether this process can ever yield net energy pro- Iimits to how many fusion reactions can be induced

duction depends on increasing the number of fusion by a single muon. If muon-catalysis proves to be feareactions per muon, The number is not yet high enough sible in principle, a substantially increased level of effor the process to be scientifically feasible, and fun- fort and a more detailed comparison of its potential

damental limits may prevent it from ever being so. benefits and liabilities to those of the other fusion apMuon-catalysis research, currently at a very prelimi- proaches may be warranted.

nary stage, focuses primarily on understanding the
Appendix C

Data for Figures

Chapter Three

Data for Figure 3-1 .— Historical Fusion Funding, 1951-88 (millions of 1986 dollars)

Operating Capital equipment Construction

Budget Budget Budget Budget

1.1

1.8

6.1

7.4

11.6

29.2

28.9

33.7

30.0

24.8

25.5

22.6

23.1

23.1

23.9

26.6

29.7

34.3

32.2

33.3

39.7

57.4

118.2

166.3

52.9

316.3

332.4

355.1

350.3

393.6

451.2

461.3

468.4

429.6

361.5

327.3

320.1

1.1

1.8

4.7

6.6

10.7

18.4

27.0

31.0

29.0

23.0

24.2

21.0

21.3

21.8

22.4

24.7

26.5

27.7

28.3

31.0

37.0

52.9

97.9

131.1

42.6

195.0

206.7

211.3

235.1

258.3

295.1

373.8

391.1

369.6

320.5

302.2

286.1

Year authority authority Index authority Index authority Index

1951 -53 . . . . . . . . . 0.200 a a

1954 . . . . . . . . . . . .

1955 . . . . . . . . . . . .

1956 . . . . . . . . . . . .

1957 . . . . . . . . . . . .

1958 . . . . . . . . . . . .

1959. . . . . . . . . . . .

1960. . . . . . . . . . . .

1961 . . . . . . . . . . . .

1962. . . . . . . . . . . .

1963. . . . . . . . . . . .

1964. . . . . . . . . . . .

1965. . . . . . . . . . . .

1966. . . . . . . . . . . .

1967. . . . . . . . . . . .

1968. . . . . . . . . . . .

1969. . . . . . . . . . . .

1970. . . . . . . . . . . .

1971 . . . . . . . . . . . .

1972. . . . . . . . . . . .

1973. . . . . . . . . . . .

1974. . . . . . . . . . . .

1975. . . . . . . . . . . .

1976. . . . . . . . . . . .

TQb 

. . . . . . . . . . . .

1977. . . . . . . . . . . .

1978. . . . . . . . . . . .

1979. . . . . . . . . . . .

1980. . . . . . . . . . . .

1981 . . . . . . . . . . . .

1982. . . . . . . . . . . .

1983. . . . . . . . . . . .

1984. . . . . . . . . . . .

1985. . . . . . . . . . . .

1986. . . . . . . . . . . .

1987 (estimate). .

1988 (request). . .

aNo expenditures occurred in this category during the war

bThe start of the fiscal year was changed in 1976 from July 1 to October 1. TQ represents the budget for the transition quarter from July 1, 1976 to September 30, 1976

SOURCE U.S Department of Energy, Officeof Energy Research, letter to OTA project staff, Aug 15, 1966, updated by personal communication to OTA staff Sept 2,1987

0.202

0.203

0.202

0.205

0.212

0.218

0.220

0.224

0.226

0.228

0.231

0.234

0.238

0.243

0.252

0.263

0.277

0.291

0.310

0.320

0.353

0.382

0.429

0.429

0.459

0.493

0.529

0.588

0.674

0.766

0.829

0.892

0.938

1.000

1.043

1.080

a

a

a

a

a

a

2.2

1.0

1.8

1.3

1.6

1.8

1.3

1.5

1.8

1.6

2.0

2.1

2.1

2.5

4.3

19.8

17.0

4.5

23.0

29.6

27.2

29.8

36.9

42.0

39.5

37.8

27.5

28.3

17.1

18.1

0.260

0.260

0.261

0.262

0.263

0.266

0.269

0.276

0.285

0.295

0.305

0.319

0.327

0.334

0.351

0.376

0.489

0.489

0.518

0.568

0.619

0.684

0.777

0.847

0.893

0.947

0.954

1.000

1.051

1.088

a

1.4

0.8

0.9

10.8

1.9

0.5

a

a

a

a

a

a

a

0.1

1.6

4.6

1.8

0.2

0.2

0.2

0.5

18.2

5.8

98.3

96.1

116.6

85.4

98.5

114.1

48.0

39.5

32.5

12.7

8.0

15.9

0.162

0.167

0.175

0.182

0.189

0.196

0.247

0.264

0.284

0.310

0.344

0.368

0.393

0.444

0.484

0.484

0.516

0.564

0.613

0.675

0.746

0.814

0.865

0.882

0.934

1.000

1.025

1.060

209
210 ● Starpower: The U.S. and the International Quest for Fusion Energy

Data for Figure 3-2.— Historical Fusion Funding, 1951-88 (millions of current dollars)

Presidential Total Presidential Total

budget request budget authority budget request budget authority

Year budget authority (in millions) Year budget authority (in millions)

1951-53 . . . . . . . . . . . . . a 1.1 1972 . . . . . . . . . . . . . . . . a 33.3

1954 . . . . . . . . . . . . . . . . a 1.8 1973 . . . . . . . . . . . . . . . . a 39.7

1955 . . . . . . . . . . . . . . . . a 6.1 1974 . . . . . . . . . . . . . . . . a 57.4

1956 . . . . . . . . . . . . . . . . a 7.4 1975 . . . . . . . . . . . . . . . . 102.3 118.2

1957 . . . . . . . . . . . . . . . . a 11.6 1976 . . . . . . . . . . . . . . . . 144.2 166.3

1958 . . . . . . . . . . . . . . . . a 29.2 TQb 

. . . . . . . . . . . . . . . . 44.4 52.9

1959 . . . . . . . . . . . . . . . . a 28.9 1977 . . . . . . . . . . . . . . . . 291.1 316.3

1960 . . . . . . . . . . . . . . . . a 33.7 1978 . . . . . . . . . . . . . . . . 370.9 332.4

1961 . . . . . . . . . . . . . . . . a 30.0 1979 . . . . . . . . . . . . . . . . 334.0 355.1

1962 . . . . . . . . . . . . . . . . a 24.8 1980 . . . . . . . . . . . . . . . . 364.1 350.3

1963 . . . . . . . . . . . . . . . . a 25.5 1981 . . . . . . . . . . . . . . . . 403.6 393.6

1964 . . . . . . . . . . . . . . . . a 22.6 1982 . . . . . . . . . . . . . . . . 460.0 451.2

1965 . . . . . . . . . . . . . . . . a 23.1 1983 . . . . . . . . . . . . . . . . 444.1 461.3

1966 . . . . . . . . . . . . . . . . a 23.1 1984 . . . . . . . . . . . . . . . . 467.0 468.4

1967 . . . . . . . . . . . . . . . . a 23.9 1985 . . . . . . . . . . . . . . . . 482.7 429.6

1968 . . . . . . . . . . . . . . . . a 26.6 1986 . . . . . . . . . . . . . . . . 390.0 361.5

1969 . . . . . . . . . . . . . . . . a 29.7 1987 (estimate). . . . . . . 333.0 341.4

1970 . . . . . . . . . . . . . . . . a 34.3 1988 (request) . . . . . . . 345.6

1971 . . . . . . . . . . . . . . . . a 32.2

aPresidential budget requests before 1975 were not available from DOE.

bThe start of the fiscal year was changed in 1976 from July 1 to October 1. TQ represents the budget for the transition quarter frorn July l, 1976 to September 30,1976,

SOURCE: US. Department of Energy, Office of Energy Research, letter to OTA project staff, Aug. 15, 1986.

Chapter Six

Data for Figure 6-1.— Federal Funding of Plasma Physics in 1984 (millions of 1984 dollars)

Plasma Physics Area DOE NSF DoD NASA NOAA Total

General Plasma Physics . . . . . . . . . . . 3 3 68 0 0 74

Magnetic Conf. Fusion . . . . . . . . . . . . 471 0 0 0 0 471

Inertial Conf. Fusion . . . . . . . . . . . . . . 170 0 0 0 0 170

Space/Astrophysical Plasma . . . . . . . 2 30 5 100 2 139

Total . . . . . . . . . . . . . . . . . . . . . . . . . . 646 33 73 100 2 854

DOE = Department of Energy

NSF = National Science Foundation

DoD = Department of Defense

NASA = National Aeronautics and Space Administration

NOAA = National Oceanic and Atmospheric Administration

SOURCE: National Research Council, Physics Through the 1990s: Plasmas and Fluids (Washington, DC: National Academy Press, 1986), p. 33

Data for Figure 6-2.— Defense and Civilian Federal Research and

Development Expenditures (billions occurrent dollars)

Year Defense Civilian Total

1982 . . . . . . . . . . . . . . . . . . . . . . . 22.9 15.8 38.7

1983 . . . . . . . . . . . . . . . . . . . . . . . 25.6 14.4 40.0

1984 . . . . . . . . . . . . . . . . . . . . . . . 30.5 15.5 46.0

1985. . . . . . . . . . . . . . . . . . . . . . . 34.7 17.0 51.7

1986. . . . . . . . . . . . . . . . . . . . . . . 37.6 17.0 54.6

1987 (estimate) . . . . . . . . . . . . . 41.2 18.6 59.8

1988 (request) . . . . . . . . . . . . . . 48.1 21.3 69.4

NOTE: Defense: includes Department of Defense along with Department of Energy atomic energy defense

activities. civilian: Includes all Federal research and development not included in defense.

SOURCE: American Association for the Advancement of Science, AAAS Report XII Research and development FY 1988

(Washington, DC: American Association for the Advancement of Science, 1987)
App, C—Data for Figures ● 211

Data for

Figure 6-3.— Major Components in Federally Funded Research and Development (in 1987 dollars)

and

Figure 6-4.— Historical Component Funding Levels for Federal Research and Development (billions of current dollars)

Year Defense Energy Space Health Science Other

1982 . . . . . . . . . . . . . . . . . . . . . . . 22.9 3.5 3.6 4.1 1.5 3.1

1983 . . . . . . . . . . . . . . . . . . . . . . . 25.6 2.9 1.7 4.5 1.6 3.7

1984. . . . . . . . . . . . . . . . . . . . . . . 30.5 2.6 2.0 5.1 1.9 3.9

1985. . . . . . . . . . . . . . . . . . . . . . . 34.7 2.5 2.4 5.8 2.1 4.2

1986. . . . . . . . . . . . . . . . . . . . . . . 37.6 2.4 1.9 5.9 2.1 4.7

1987 (estimate) . . . . . . . . . . . . . 41.2 2.2 2.4 7.0 2.2 4.8

1988 (request) . . . . . . . . . . . . . . 48.1 2.0 3.1 9.0 2.6 4.7

NOTE Defense Includes Department of Defense along with Department of Energy atomic energy defense activites Energy Includes Department of Energy activites,

Iess general science and defense, Nuclear Regulatory Commission, and Environmental Protection Agency Space includes National Aeronautics and Space Ad.

ministration less space applications and aeronautical research Health includes Department of Health and Human Services, Veterans Administration, Department of Education, and Environmental Protection Agency Science includes National Science Foundation and Department of Energy high energy physics and

nuclear physics

SOURCE American Association for the Advancement of Science, AAAS Report X// Research and Development FY 1988 (Washington, DC American Association for

the Advancement of Science, 1987)

Data for Figure 6-5.— Annual Appropriations of DOE Civilian Research and Development Programs

(millions of current dollars)

Year Solar/renewables a Fusion Fission Fossil Conservation

1980 . . . . . . . . . . . . . . . . . . . . . . .

1981 . . . . . . . . . . . . . . . . . . . . . . .

1982 . . . . . . . . . . . . . . . . . . . . . . .

1983 . . . . . . . . . . . . . . . . . . . . . . .

1984 . . . . . . . . . . . . . . . . . . . . . . .

1985 . . . . . . . . . . . . . . . . . . . . . . .

1986 (estimate) . . . . . . . . . . . . .

1987 (estimate) . . . . . . . . . . . . .

1988 (request) . . . . . . . . . . . . . .

731.4

711.2

341.1

261.2

211.9

201.7

173.6

146.3

93.5

350.3

393.6

451.2

461.3

468.4

429.6

361.5

341.4

345.6

847.8

817.0

819.4

701.7

622.9

412.6

358.1

329.3

336.4

847.8

821,3

566.8

310.9

331.5

349.4

343.0

451.0

368.5

296.1

292.5

151.9

133.5

150.1

175.5

170.9

160.7

80.1

aSolar/Renewables Includes Solar, Geothermal, and Hydroelectric programs.

SOURCE: Fusion—U S Department of Energy, Off Ice of Energy Research, letter to OTA project staff, Aug 15, 1986 Others –’’Analysis of Trends in Civilian R&D Appropriations for the U.S. Department of Energy, ” prepared by Argonne National Laboratory, August 1986, table B 3, p 49

Data for Figure 6-6.— Major DOE Civilian Research and

Development Funding at National Laboratories in

Fiscal Year 1987 (millions of 1987 dollars)

Solar and Other Renewable . . . . . . . . . . . . . . .

Electric Systems . . . . . . . . . . . . . . . . . . . . . . . . .

Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Conservation . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Fossil Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Supporting Research. . . . . . . . . . . . . . . . . . . . . .

Nuclear Energy . . . . . . . . . . . . . . . . . . . . . . . . . .

Magnetic Fusion . . . . . . . . . . . . . . . . . . . . . . . . .

$114.5

19.6

133.3

49.5

116.6

360.0

254.3

245.6

SOURCE U S Department of Energy. FY 1988 Congresslonal Budget Estlmates

for /laboratory/P/anf, January 1987
212 ● Starpower: The U.S. and the International Quest for Fusion Energy

Chapter Seven

Data for

Figure 7-1 .—Comparison of International Fusion Budgets (current dollars)

and

Figure 7.2.—Comparison of International Equivalent Person-Years

United States:

Fusion budget Average industrial hourly

Year (in millions $) wage ($) Person-years

1980 . . . . . . . . . . . . . . . . . . . . . . . 350.3 7.27 23,165

1981 . . . . . . . . . . . . . . . . . . . . . . . 393.6 7.99 23,683

1982 . . . . . . . . . . . . . . . . . . . . . . . 451.2 8.50 25,520

1983 . . . . . . . . . . . . . . . . . . . . . . . 461.3 8.84 25,088

1984. . . . . . . . . . . . . . . . . . . . . . . 468.4 9.16 24,584

1985. . . . . . . . . . . . . . . . . . . . . . . 429.6 9.57 21,582

1986. . . . . . . . . . . . . . . . . . . . . . . 361.5 10.04 17,310

Japan:

Fusion budget Fusion budget Average industrial Average industrial

Year (yen) (in millions $) hourly wage (yen) hourly wage($) Person-years

1980 . . . . . . . . . . . . 52,256 230 1,293 5.70 19,430

1981 . . . . . . . . . . . . 61,115 277 1,373 6.22 21,400

1982 . . . . . . . . . . . . 72,025 289 1,225 5.72 24,300

1983 . . . . . . . . . . . . 69,112 291 1,490 6.28 22,300

1984 . . . . . . . . . . . . 60,392 251 1,561 6.50 18,600

1985 . . . . . . . . . . . . 65,154 271 1,640 6.83 19,100

1986 . . . . . . . . . . . . 64,861 381 1,704 10.02 18,300

European Community:

Fusion budget Fusion budget Average industrial

Year (MECU) (in millions $) hourly wage($) Person-Years

1980 . . . . . . . . . . . . . . . . . 190 264 5.93 21,404

1981 . . . . . . . . . . . . . . . . . 225 254 5.35 22,815

1982 . . . . . . . . . . . . . . . . . 300 297 5.20 27,457

1983 . . . . . . . . . . . . . . . . . 300 300 5.06 28,532

1984 . . . . . . . . . . . . . . . . . 350 298 4.60 31,086

1985 . . . . . . . . . . . . . . . . . 350 245 4.06 28,977

1986 . . . . . . . . . . . . . . . . . 375 338 5.60 28,990

SOURCE: U.S. Department of Energy, Office of Energy Research, staff memorandum to file. Oct.9, 1986

Data for Figure 7-3.— Comparison of international Fusion Budgets by Percentage Gross National Producta

United States European Community Japan

Year GNP Fusion/GNP GNPb

Fusion/GNP GNP Fusion/GNP

1980 . . . . . . . . . . . . . . . . . 2,632 0.0133 1,962 0.0135 899 0.0271

1981 . . . . . . . . . . . . . . . . . 2,958 0.0133 2,131 0.0119 964 0.0287

1982 . . . . . . . . . . . . . . . . . 3,069 0.0147 2,277 0.0130 1,060 0.0273

1983 . . . . . . . . . . . . . . . . . 3,305 0.0139 2,394 0.0125 1,138 0.0256

1984 . . . . . . . . . . . . . . . . . 3,363 0.0128 data unavailable data unavailable

aAll Gross National Products are shown in billions of current dollars

bThe GNP for the European Community is computed by adding the GNP’s of the major EC countries (Belgium, France. Federal Republic of Germany, Greece, Italy,

Netherlands, and the United Kingdom)

SOURCE. Gross National Products found in Statistical Abstract, No 1742
Appendix D

List of Acronyms and Glossary

AEC

ASDEX-U

ATF

CERN

CIT

COCOM

CPMP

CPRF

D Ill

D II I-D

Acronyms

–Atomic Energy Commission

–Axisymmetric Divertor Experiment

Upgrade; Garching, Federal Republic of Germany

–Advanced Toroidal Facility; Oak Ridge

National Laboratory, Oak Ridge, Tennessee

–European Laboratory for Nuclear Research (after its original French

acronym)

–Compact Ignition Tokamak; proposed

for the Princeton Plasma Physics Laboratory, Princeton, New Jersey

–Coordinating Committee

–Comprehensive Program Management

Plan

–Confinement Physics Research Facility; under construction at Los Alamos

National Laboratory, Los Alamos, New

Mexico

–Doublet ill; GA Technologies Inc.,

San Diego, California

–Doublet Ill Upgrade; GA Technologies, San Diego, California

D-D Reaction– Deuterium-deuterium fusion reaction

(see Glossary)

D-T Reaction —Deuterium-tritium fusion reaction

DoD

DOE

dpa

EC

ECRH

EPRI

ERAB

ERDA

ESECOM

ETR

eV

FED

FER

FPA

(see Glossary)

–U.S. Department of Defense

–U.S. Department of Energy

–displacements per atom

–European Community

—electron cyclotron resonance heating

(see Glossary)

—Electric Power Research Institute;

Palo Alto, California

–Energy Research Advisory Board

–Energy Research and Development

Administration

–Senior Committee on Economic, Safety,

and Environmental Aspects of Magnetic Fusion Energy

—engineering test reactor (see Glossary)

—electron volt (see Glossary)

–Fusion Engineering Device

–Fusion Experimental Reactor (proposed

Japanese engineering test reactor)

—Fusion Power Associates; Gaithersburg, Maryland

FRC

GA

GNP

IAEA

ICRH

IEA

IFF

INTOR

ITER

JAERI

JET

JIFT

JT-60

LANL

LCT

LLNL

LMFBR

LWR

MFAC

MFECC

MFEE Act

MFPP

MFTF-B

MI T

NASA

NET

NIH

NRC

NSF

OER

–field-reversed configuration

(see Glossary)

–GA Technologies Inc.; San Diego,

California

–gross national product

–International Atomic Energy Agency

—ion cyclotron resonance heating

(see Glossary)

–International Energy Agency

–Integrated Fusion Facility

—International Tokamak Reactor

—International Thermonuclear Experimental Reactor

–Japan Atomic Energy Research institute

–Joint European Torus; Abingdon, UK

–Joint Institute for Fusion Theory; University of Texas at Austin, Texas, and

Nagoya University in Japan

–Japan Tokamak-60

–Los Alamos National Laboratory; Los

Alamos, New Mexico

–Large Coil Task; Oak Ridge National

Laboratory, Oak Ridge, Tennessee

—Lawrence Livermore National Laboratory; Livermore, California

–liquid metal fast breeder reactor

(fission–see Glossary)

–light-water reactor

(fission–see Glossary)

—Magnetic Fusion Advisory Committee

–Magnetic Fusion Energy Computing

Center; Lawrence Livermore National

Laboratory, Livermore, California

–Magnetic Fusion Energy Engineering

Act of 1980 (Public Law 96-386)

–Magnetic Fusion Program Plan

–Mirror Fusion Test Facility B at

Lawrence Livermore National Laboratory, Livermore, California

–Massachusetts Institute of Technology; Cambridge, Massachusetts

–U.S. National Aeronautics and Space

Administration

—Next European Torus (proposed European engineering test reactor)

–U.S. National Institutes of Health

–U.S. Nuclear Regulatory Commission

–U.S. National Science Foundation

–Office of Energy Research in the U.S.

Department of Energy

213
214 ● Starpower: The U.S. and the International Quest for Fusion Energy

OFE

OHTE

ORNL

OTR

PBX-M

PPPL

Q

RF

RFP

TEXT

TEXTOR

TFTR

TMX

TMX-U

Tokamak

TPA

TSTA

UCLA

UFA

UK

–Office of Fusion Energy in the Office

of Energy Research, U.S. Department

of Energy

–Ohmically Heated Toroidal Experiment; GA Technologies Inc., San

Diego, California

–Oak Ridge National Laboratory; Oak

Ridge, Tennessee

–Operational Test Reactor (proposed

Soviet engineering test reactor)

–Princeton Beta Experiment Modification; Princeton Plasma Physics Laboratory, Princeton, New Jersey

–Princeton Plasma Physics Laboratory;

Princeton, New Jersey

–Energy Gain (see Glossary)

—radiofrequency

—reversed-field pinch (see Glossary)

–Texas Experimental Tokamak; University of Texas Fusion Research Center in Austin, Texas

–Tokamak Experiment for Technology

Oriented Research; Julich, Federal

Republic of Germany

–Tokamak Fusion Test Reactor; Princeton Plasma Physics Laboratory, Princeton, New Jersey

—Tandem Mirror Experiment; Lawrence

Livermore National Laboratory, Livermore, California

–Tandem Mirror Experiment Upgrade;

Lawrence Livermore National Laboratory, Livermore, California

–Toroidal magnetic chamber, in Russian (see Glossary)

–Technical Planning Activity

–Tritium Systems Test Assembly; Los

Alamos National Laboratory, Los

Alamos, New Mexico

–University of California at Los Angeles

–University Fusion Associates

–United Kingdom

Glossary

Acid deposition: A consequence of fossil fuel combustion in which combustion byproducts emitted

as gases react in the atmosphere and are deposited on earth in the form of acidic substances. Also

called “acid rain. ”

Activation product: Material made radioactive through

exposure to neutrons in fission or fusion reactors.

Active protection: The condition in which the safety

of a nuclear reactor can be assured only through

the proper design and operation of active safety systems. See “Passive protection. ”

Advanced tokamak: A tokamak incorporating features

such as steady-state current drive or shaping of the

plasma in order to attain higher performance or

more efficient operation than the conventional

tokamak. See “Tokamak” or “conventional

tokamak.”

Afterheat: Heat produced by the continuing decay

of radioactive atoms in a nuclear reactor after fission or fusion reactions have stopped. Afterheat i n

a fission reactor originates primarily in the fuel rods;

in a fusion reactor it would result mainly from induced radioactivity in the reactor structure.

Alpha particle: A positively charged particle, identical to a helium-4 nucleus, composed of two protons and two neutrons. An alpha particle is emitted in the radioactive decay of many naturally

occurring radioisotopes such as uranium and thorium; it is also one of the products of the D-T fusion reaction.

Alternate confinement concept: A fusion magnetic

confinement concept other than the tokamak.

Anomalous transport: Loss of energy from tokamak

plasmas due to escaping electrons that occurs at

a rate several times higher than that predicted by

present theory.

Ash: The end-product of a fusion reaction. For the D-T

fusion reaction, the “ash” is helium gas.

Atom: A particle of matter indivisible by chemical

means that is the fundamental building block of a

chemical element. The dense inner core of the

atom, called the nucleus, contains protons and

neutrons and constitutes almost all the mass of the

atom. The nucleus is surrounded by a cloud of orbiting electrons. Atoms contain equal numbers of

positively charged protons and negatively charged

electrons and as a whole are electrically neutral.

An atom is a few billionths of an inch in diameter,

and several sextillion (1 followed by 21 zeros)

atoms are found i n an ordinary drop of water.

Atomic nucleus: See “Nucleus.”

Auxiliary heating: External systems that heat Plasmas

to higher temperatures than can be reached from

the heat generated by electric currents within the

plasma. Neutral beam heating and radiofrequency

heating are both examples of auxiliary heating

systems.

Axial: The direction in a cylinder parallel to the central axis of the cylinder.

Background radiation: Naturally occurring sources of

radiation. Primary sources are cosmic rays and naturally occurring radioactive isotopes that are found

in the earth or are produced in the atmosphere by

cosmic rays.
App. D—List of Acronyms and Glossary ● 215

Balance of plant: Those systems in a fusion reactor

not associated with producing or controlling the fusion reaction. Systems i n the balance of plant convert the heat produced by fusion reactions into

electricity. See also “Fusion power core.”

Beta: The ratio of the outward pressure exerted by the

plasma to the inward pressure that the magnetic

confining field is capable of exerting. Beta is equivalent to the ratio of the energy density of particles

in the plasma to the energy density of the confining magnetic fields.

Beta particle: A high-energy electron emitted in the

decay of certain radioactive isotopes.

Bilateral agreement: An agreement between two

nations.

Biologically active: Substances that are absorbed by

living organisms and are utilized in biological processes. Radioactive substances that are biologically

active (e. g., radioactive iodine or strontium isotopes) become incorporated into living organisms.

Blanket: Structure surrounding the plasma in a fusion

reactor within which the fusion-produced neutrons

are slowed down, heat is transferred to a primary

coolant, and tritium is bred from lithium.

Breakeven: The point at which the fusion power generated in a plasma equals the amount of heating

power that must be added to the plasma to sustain

its temperature.

Breakeven-equivalent: Attainment in a non-tritiumcontaining plasma of conditions (temperature, density, and confinement time) that would result in

breakeven if the plasma contained tritium. Because

plasmas not containing tritium are far less reactive

than those containing tritium, the actual amount

of fusion power generated by a breakeven-equivaIent plasma will be far less than would be produced

under actual breakeven conditions.

Breeder reactor: A nuclear reactor that produces

more fissionable fuel than it consumes. Breeders

produce fissionable fuel by irradiating fertile materials with neutrons. See “Fertile material.”

Breeding ratio: The number of tritium atoms produced in the blanket of a fusion reactor for each

tritium atom consumed in the fusion plasma.

Burn control: The mechanism by which the power

level of a self-sustaining fusion reaction is regulated.

Capital-intensive: An energy-generating technology

in which most of the cost of energy is due to the

fixed cost of the capital investment in the generating station, as opposed to variable fuel or operations and maintenance expenditures.

Carbon dioxide (C02

): An inherent product of the

combustion of fossil fuels. Buildup of carbon dioxide i n the earth’s atmosphere as a result of fossil

fuel use may affect global climate. See “Greenhouse effect.”

Central cell: In the tandem mirror confinement concept, the central cell is the region where most of

the power-producing fusion reactions would occur.

Plasma in the central cell is kept from escaping by

electric fields generated by the end cells. See “End

Centrifugal injector: Device that uses centrifugal force

to inject pellets of frozen fuel into fusion plasmas.

Chlorofluorocarbons: Manmade chemicals, used as

refrigerants, industrial solvents, and for other purposes, which have heat-retaining properties similar to

carbon dioxide when released into the atmosphere.

Cladding: In a fission reactor, the material that encloses nuclear fuel.

Classical confinement: The best possible plasma confinement, in which the only mechanism by which

particles escape the plasma is through rare, but inevitable, collisions between plasma particles that

cause them to migrate across the magnetic field

towards the plasma edge. Classical confinement is

also referred to as “classical diffusion. ’

Classification: Restricting the dissemination of certain

information for reasons of national security. Only

people holding security clearances granted by the

government are permitted access to classified information.

Closed confinement concept: Magnetic configuration

in which the plasma is confined by magnetic lines

of force that do not lead out of the device. Closed

confinement concepts all have the basic shape of

a doughnut or inner tube, which is called a torus.

Collaboration: An intensive type of international cooperation involving a substantial degree of program

integration, funding commitment, and joint management.

Commercial feasibility: Fusion power’s acceptance

in the marketplace as a source of energy that is

environmentally and socially acceptable and economically competitive when compared to alternate

sources of energy.

Compact toroids: A class of magnetic confinement

configurations in which the chamber containing the

plasma need not have a central hole through which

external magnet coils must pass. Examples are the

spheromak and the field-reversed configuration.

Compression heating: Method of heating a plasma by

compressing it into a smaller volume. The plasma

is compressed by modifying the external magnetic

fields.

Conceptual design: The basic or fundamental design

of a fusion reactor or experiment that sketches out

device characteristics, geometry, and operating features but is not at the level of detail that would permit construction.

72-678 0 - 97 . (5
.

216 ● Starpower: The U.S. and the International Quest for Fusion Energy

Confinement: Restraint of plasma within a designated

volume. In magnetic confinement, this restraint is

accomplished with magnetic fields.

Confinement concept: A particular configuration of

magnetic fields used to confine a fusion plasma.

Various confinement concepts differ in the shape

of their magnetic fields and in the manner in which

these fields are generated.

Confinement parameter: The product of plasma density and confinement time that, along with temperature, determines the ratio between power produced

by the plasma and power input to the plasma. Also

called “Lawson parameter. ”

Confinement time: A measure of how well the heat

in a plasma is retained. The confinement time of

a plasma is the length of time it would take the

plasma to cool down to a certain fraction of its initial temperature if no heat were added.

Confining magnets: External magnets used to generate the confining magnetic fields in a fusion device.

Containment building: In a fission reactor, the containment building is a thick concrete structure surrounding the pressure vessel that encloses the reactor core and other components. It is designed to

prevent radioactive material from being released

to the atmosphere in the unlikely event that anything should escape from the pressure vessel. The

need for containment buildings for fusion reactors

has not vet been determined.

Conventional tokamak: A tokamak device not incorporating advanced steady-state current drive or

plasma shaping technology. See “Tokamak,” “Advanced tokamak. ”

Coolant: Fluid that is circulated through a component

or system to remove heat. In a fusion reactor, the

coolant would flow through the blanket to remove

the heat generated by fusion reactions.

Cooperation: In the context of international activities,

cooperation refers to all activities involving nations

or individuals from different nations working together.

Critical temperature: The temperature below which

a superconducting material loses all resistance to

electricity. See “Superconductivity.”

Curie: A unit of radioactivity. One curie of a radioactive substance is that amount that undergoes 3.7

x 1010 (37 billion) nuclear transformations per

second,

D-D reaction: Fusion reaction in which one nucleus

of deuterium fuses with another. Two different outcomes are possible: a proton plus a tritium nucleus,

or a neutron plus a helium-3 nucleus.

D-T reaction: Fusion reaction in which a nucleus of

deuterium fuses with a nucleus of tritium, forming

an alpha particle and a neutron and releasing 17.6

million electron volts of energy. The D-T reaction

is the most reactive fusion reaction.

Decay heat: See “Afterheat.”

Decommissioning: The steps taken to render a plant,

particularly a nuclear reactor, safe to the environment at the end of its operating lifetime.

Dense z-pinch: An open confinement concept in

which a strong electrical current is suddenly passed

through a fiber of frozen D-T fuel, turning it into

a plasma and at the same time generating a powerful encircling magnetic field to confine the plasma.

The dense z-pinch is in a very preliminary stage of

development.

Density: Amount per unit volume. By itself, the term

“density” often refers to particle density, or the

number of particles per unit volume. However,

other quantities such as energy density or power

density (energy or power per unit volume, respectively) can also be defined.

Detritiation systems: Systems to remove tritium from

air or water that are important to ensure the safety

of tritium-handling facilities.

Deuterium (D or 2H): A naturally occurring isotope

of hydrogen containing one proton and one neutron in its nucleus. Approximately one out of 6,700

atoms of hydrogen in nature is deuterium. Deuterium is one of the fuels (along with tritium) needed

for the D-T fusion reaction, the most reactive fusion reaction.

Diagnostics: The procedure of determining (diagnosing) exactly what is happening inside an experimental device during an experiment. Also, the instruments used for diagnosing.

Diffusivity: The ability of a substance, especially a gas,

to diffuse through another substance.

Direct conversion techniques: Conversion of the kinetic energy of plasma particles directly into electrical energy without first converting it into heat.

Since conversion into heat and the subsequent reconversion to electricity impose inherent inefficiencies, direct conversion could improve the efficiency

of a fusion generating station.

Divertor: A component of a toroidal fusion device

used to shape the magnetic field near the plasma

edge so that particles at the edge are diverted away

from the rest of the plasma. These particles are

swept into a separate chamber where they strike

a barrier, become neutralized, and are pumped

away. In this way, energetic particles near the

plasma edge are captured before they can strike

the walls of the main discharge chamber and generate secondary particles that would contaminate

and cool the plasma. Diverters have also been
App. D—List of Acronyms and Glossary ● 217

found to be responsible for establishing a mode of

enhanced tokamak confinement called the “Hmode. ” See “H-mode scaling.”

Driven fusion reactor: A fusion reactor operating below breakeven that must be driven with more

energy than it produces. Such a reactor might serve

to generate neutrons for a fusion materials test facility.

Electromagnetic radiation: Radiation consisting of

associated and interacting electric and magnetic

fields that travel in a wave at the speed of light. Radio waves, microwaves, light, x-rays, and gamma

rays are all forms of electromagnetic radiation; they

differ from one another in wavelength and frequency.

Electron: An elementary particle with a unit negative

electrical charge and a mass 1/1 837 that of a proton. In an atom, electrons surround the positively

charged nucleus and determine the atom’s chemical properties.

Electron cyclotron frequency: The frequency at

which electrons in a plasma gyrate about magnetic

field lines. The electron cyclotron frequency increases with increasing magnetic field strength and

is typically hundreds of gigahertz, substantially

higher than the ion cyclotron frequency. See also

“ion cyclotron frequency. ”

Electron cyclotron resonance heating (ECRH): A

process in which only electrons gain energy from

an applied radiofrequency field operating at the

electron cyclotron frequency. The electrons then

heat other plasma particles through collisions.

Electron temperature: The temperature of the electrons in a plasma. Electron temperature can differ

from ion temperature. Some of the mechanisms by

which energy is lost from the plasma, in particular

radiation losses, depend on electron temperature.

Electron volt (eV): A unit of energy equal to the

energy that can be acquired by singly charged particle (e.g., an electron) from a one-volt battery.

Since the temperature of a system is proportional

to the average energy of each particle in the system, temperature is also measured in electron volts;

at a temperature of 1 eV, equal to 11,6050 K, the

average energy of each particle is roughly 1 eV. As

a unit of energy, one eV equals 1.602 X 10-19 Joule,

3.827 X 10-20 calorie, 1.519 X 10-22 Btu, or 4.45

X 10-26 kilowatt-hour.

End cell: In the tandem mirror confinement concept,

the end cell is a magnetic mirror used to plug each

end of the central cell. The function of the end cell

is to generate an electric field that will keep the

plasma in the central cell from leaking out. See also

“Central cell.”

Energy gain (Q): The ratio of the fusion power produced by a plasma to the amount of power that

must be added to the plasma to sustain its temperature.

Engineering feasibility: The ability to design and construct all the components, systems, and subsystems

required for a fusion reactor.

Engineering test reactor: A next-generation fusion experiment to study the physics of long-pulse ignited

plasmas, provide opportunities to develop and test

reactor blanket components under actual fusion

conditions, and integrate the various systems of a

fusion reactor.

Equivalent Q: For a plasma not containing tritium, a

measure of what Q would have been i n a tritiumcontaining plasma that attained the same temperature and confinement parameter. See “Confinement parameter. ”

External heating: See “Auxiliary heating. ”

External magnets: Magnet coils outside the fusion

plasma that generate those confining magnetic

fields that are not generated by currents within the

plasma itself.

Fast breeder reactor: A fission reactor in which fast

neutrons are used both to induce fission reactions

in the fuel, producing power, and to react with fertile materials, converting them to more fissile fuel.

See “Fast neutron,” “Fertile material, ” and “Fissile material. ”

Fast neutron: A neutron with energy greater than

100,000 electron volts.

Fertile material: Material that is not fissile but can be

converted to fissile material through neutron irradiation. See “Fissile material. ”

Field-reversed configuration (FRC): A magnetic confinement concept with no toroidal field, in which

the plasma is essentially cylindrical in shape. The

FRC is a form of compact toroid.

Financial liability: Costs, including those associated

with death, injury, property damage, and loss of

revenue, to which an electric utility would be exposed in the event of the worst credible accident

attributable to a generating station.

Fine-scale plasma instabilities: Turbulence and other

instabilities occurring over distances the size of the

orbits of individual plasma particles (electrons and

ions) about magnetic field lines. Also called “microin stabilities.”

First wall: The first physical boundary that surrounds

the plasma. The first wall can refer either to the surface of the blanket that faces the plasma, or to a

separate component between the blanket and the

plasma.
218 ● Starpower: The U.S. and the International Quest for Fusion Energy

Fissile material: Material that can be used as fuel in

fission reactors.

Fission: The process by which a neutron strikes a nucleus and splits it into fragments. During the process of nuclear fission, several neutrons are emitted

at high speed, and heat and radiation are released.

Fission/fusion hybrid: A reactor using a fusion core

to produce neutrons that in turn either induce fission reactions or breed fissile fuel in the reactor

blanket. Fission/fusion hybrid reactors can produce

energy, fissile fuel, or both.

Flux: The amount of a quantity (heat, neutrons, etc.)

passing through a given area per unit time.

Fossil plant: A powerplant fueled by coal, oil, or gas.

Fusion: The process by which the nuclei of light elements combine, or fuse, to form heavier nuclei, releasing energy.

Fusion power core: That portion of a fusion reactor

containing all the systems having to do specifically

with the fusion process, such as the plasma chamber, the blanket, the magnets, and the heating, fueling, and impurity control systems.

Fusion self-heating: Heat produced within a plasma

from fusion reactions. Since alpha particles produced in fusion reactions remain trapped within the

plasma, they contribute to self-heating by transferring their energy to other plasma particles in collisions. Fusion-produced neutrons, on the other

hand, escape from the plasma without reacting further and do not contribute to self-heating.

Gauss: A measure of magnetic field strength. The

strength of the earth’s magnetic field on the earth’s

surface is about one-half gauss; magnetic confinement fusion devices typically have maximum magnetic field strengths of tens of thousands of gauss.

Gigahertz: A measure of frequency equal to 1 billion

hertz, or 1 billion cycles per second. See “Hertz.”

Gravitational confinement: The fusion process that

occurs in the sun and other stars in which fusion

plasmas are confined by the gravitational fields generated by their own masses. Enormous masses (considerably more than that of the planet Jupiter) are

required for gravitational confinement.

Greenhouse effect: Possible warming of the earth due

to excess heat trapped in the atmosphere by increasing levels of carbon dioxide and other “greenhouse gases.”

Greenhouse gases: Gases such as chlorofluorocarbons, methane, nitrous oxide, and carbon dioxide

that, in the upper atmosphere, have the property

of retaining heat that would otherwise escape from

the earth to space. Accumulation of such gases may

affect global climate. See “Greenhouse effect. ”

“H-mode” scaling: A mode of tokamak behavior in

which confinement time does not degrade as increased amounts of auxiliary power are used to

heat the plasma. This scaling has been observed

in tokamaks that have diverters, and it is believed

to be closely related to conditions at the edge of

the plasma. See “L-mode scaling. ”

Half-life: The time required for one-half of the atoms

of an unstable radioactive element to decay into

atoms of other substances, Each radioisotope has

a unique half-life, which can range from fractions

of a second to billions of years.

Heads-of-state agreement: An agreement between

nations signed by their respective heads-of-state,

For the United States, the head-of-state is the

President,

Heat exchanger: A device for transferring heat from

one fluid to another without allowing them to mix.

Heat exchangers are used in nuclear reactors to

transfer heat out of the reactor core without circulating the coolant, which becomes radioactive,

through the rest of the generating station,

Heat load: The amount of heat that a reactor component must withstand. Both the choice of materials for the component and the amount of cooling

that must be provided to it depend on the component’s anticipated heat load.

Helium nucleus: See “Alpha particle, ”

Hertz: One cycle per second; a measure of frequency.

High energy gain: A fusion reaction producing many

(1 O or so) times as much power as must be input

to the reaction to maintain its temperature.

High-level waste: Radioactive waste that is extremely

radioactive and would pose a serious health and

environmental risk if released into the environment.

Disposal of high-level waste must minimize the possibility of its release.

Hydrogen (H): The lightest element. All hydrogen

atoms have nuclei containing a single proton and

have a single electron orbiting that nucleus. Three

isotopes of hydrogen exist, having O, 1, or 2 neutrons in their nuclei in addition to the proton. The

term hydrogen is also used to refer to the most common isotope, technically called “protium,” that has

no neutrons in its nucleus.

Ignition: The point at which a fusion reaction becomes self-sustaining. At ignition, fusion self-heating

is sufficient to compensate for all energy losses; external sources of heating power are no longer necessary to sustain the reaction.

Impurities: Atoms present in a plasma that are heavier than fusion fuel atoms. Impurities are undesirable because they dilute the fuel and because they
App. D—List of Acronyms and Glossary ● 219

increase the rate at which the plasma’s energy is

radiated out of the plasma.

Induced radioactivity: Radioactivity created when

non-radioactive materials are bombarded by neutrons and become radioactive. Radioactivity can be

induced in essentially any material by exposure to

neutrons, but the half-life and intensity of this radioactivity depends strongly on the material.

Industrial base: The industrial capability to design and

manufacture the components of a fusion plant, to

construct such plants, and to accomplish the preprocessing and reprocessing of fuels.

Inertia: Inertia is the property of an object to resist

external forces that would change its motion. Unless acted upon by external forces, an object at rest

will remain at rest, and an object moving in a

straight line at constant speed will continue to do

so. Under the influence of external forces, objects

with differing inertias wiII respond at different rates.

The inertia of an object depends solely on its mass.

Inertial confinement: An approach to fusion in which

intense beams of light or particles are used to compress and heat tiny pellets of fusion fuel so rapidly

that fusion reactions occur before the pellet has a

chance to expand. The pellet’s own inertia, or its

initial resistance to expansion even when it is being blown apart, holds the pellet together long

enough for fusion energy to be produced.

Information exchange: Sharing technical approaches

and experimental data through any or all of several channels, including meetings, conferences,

symposia, workshops, and publication in technical journals.

Inherent safety: In this report, inherent safety is the

abiIity to assure, solely through reliance on passive

systems and laws of physics, that no immediate offsite fatalities can result from any mechanical malfunction, operator error, or natural disaster. True

inherent safety can be assured only by having so

little hazardous material that even complete release

could not cause an off-site prompt fatality, or by

having so little stored energy that even if all the

stored energy were released at once, the resultant

explosion or fire would not be powerful enough

to disperse a fatal dose of hazardous material, See

“Active protection” and “Passive protection. ”

Instabilities: Small disturbances that become amplified, or become more intense, once they begin. A

cone balanced upside-down on its tip is subject to

an instability, since once it begins to wobble, it will

become more unbalanced until it falls over. A

stable system, on the other hand, responds to disturbances by opposing them. Small disturbances

in a stable system decrease in intensity until they

die away. If a ball sitting in the bottom of a bowl

is disturbed, for example, it wiII eventualIy come

to rest again at the bottom of the bowl.

Insulator: Material that does not conduct electricity.

Ion: An atom (or molecularly bound group of atoms)

that has become electrically charged as a result of

gaining or losing one or more orbital electrons. A

completely ionized atom is one stripped of all its

electrons.

Ion cyclotron frequency: The frequency at which ions

in a plasma gyrate about magnetic field lines. The

ion cyclotron frequency increases with increasing

magnetic field strength and is typically tens to hundreds of megahertz. See also “electron cyclotron

frequency.”

Ion cyclotron resonance heating (lCRH): A process

in which only ions gain energy from an applied

radiofrequency field operating at the ion cyclotron

frequency. The ions then heat other plasma particles through collisions.

Ion temperature: The temperature of the ions in a

plasma. Ion temperature can differ from electron

temperature. Since it is the ions that fuse i n fusion

reactions, it is the ion temperature that determines

the fusion reaction rate. See also “Electron temperature.”

Ionization: The process of removing or adding an

electron to a neutral atom, thereby giving it an electric charge and creating an ion. The term is also

used to denote removal of an electron from a partially ionized atom to make a more completely

ionized one.

Ionizing radiation: Radiation energetic enough to ionize matter that it passes through. Depending on its

intensity, ionizing radiation poses a health risk. Examples are alpha and beta particles, emitted by

radioactive substances, and electromagnetic radiation having frequencies in the far ultraviolet, x-ray,

and gamma ray regions.

Isotope: Different forms of the same chemical element

whose atoms differ i n the number of neutrons i n

the nucleus. (All isotopes of an element have the

same number of protons in the nucleus and the

same number of electrons orbiting the nucleus. )

Isotopes of the same element have very similar

chemical properties and are difficult to separate by

chemical means. However, they can have quite

different nuclear properties.

Joint construction and operation: Pooling resources

to construct and operate an experimental facility

jointly.

Joint planning: Activities between nations that coordinate experimental and theoretical programs and

identify areas of future cooperative research.
220 ● Starpower: The U.S. and the International Quest for Fusion Energy

Joint research: Making major national facilities available to researchers from other nation’s programs

in exchange for financial or technical contributions.

Kinetic energy: Energy of motion. The energy released

in a fusion reaction is originally in the form of kinetic energy of the reaction products. When these

reaction products (alpha particles and neutrons)

collide with atoms or nuclei in the plasma or in the

reactor structure, they slow down and their kinetic

energy is converted into heat.

“L-mode” scaling: Mode of tokamak behavior in

which confinement time degrades as increasing

amounts of auxiliary heating power are input into

the plasma. See “H-mode” scaling.

Large-scale plasma instabilities: Deformations of both

the overall confining magnetic field and the plasma

that can lead to sudden escape of the entire plasma

from confinement.

Laser fusion: A form of inertial confinement fusion in

which a small pellet of fuel material is compressed

and heated by a burst of laser light. See “lnertial

confinement .“

Lawson parameter: See “Confinement parameter.”

Light-water reactor (LWR): A fission reactor in which

ordinary water is used as coolant and as a neutron

moderator. See “Neutron moderator. ”

Limiter: Device placed inside the plasma chamber to

intercept particles at the edge of a plasma. By

“scraping off” these particles from the plasma edge,

the limiter defines the size of the plasma.

Liquid-metal fast breeder reactor: (LMFBR) A fission

fast breeder reactor with a liquid metal coolant. See

“Fast breeder reactor.”

Lithium (Li): A light, chemically reactive metal that

can be converted i n the blanket of a fusion reactor

into the tritium fuel needed for fusion reactions.

Load change, capability for: The mechanical and

thermal characteristics of an electric generating station that limit its rate of response to changes in load

or that restrict the time required for startup or

shutdown.

Long-lived radioactivity: Radioactive isotopes having

long half-lives.

Low-activitation materials: Materials that, under neutron irradiation, do not generate intensely radioactive, long-lived radioactive isotopes. Examples include certain vanadium alloys and ceramics such

as silicon carbide. Fusion reactors made of lowactivation materials would accumulate far less

radioactivity over their lifetimes than reactors made

with more conventional materials such as steels.

Low-activation materials also produce less afterheat

following a reactor shutdown than more conventional materials. See “Afterheat.”

Low-level waste: Waste containing sufficiently low

levels of radioactivity that it does not pose a major

health or environmental risk. Disposal of low-level

waste does not require the stringent precautions

necessary for high-level waste.

Magnetic confinement: Any means of containing and

isolating a hot plasma from its surroundings by

using magnetic fields.

Magnetic field: The property of the space near a magnet that results, for example, in the attraction of iron

to the magnet. Magnetic fields are characterized

by their direction and their strength. Electrically

charged particles moving through a magnetic field

at an angle with respect to the field are bent in a

direction perpendicular to both their direction of

motion and the direction of the field. Particles moving parallel to a magnetic field are not affected.

Therefore, magnetic fields cannot prevent plasma

particles from escaping along field lines.

Magnetic field line: A (possibly curved) line whose

direction at every point is given by the direction

of the magnetic field through that point. Electrically

charged particles in a magnetic field tend to gyrate

around magnetic field lines; they can travel along

the field lines much more easily than they can cross

field lines.

Magnetic mirror: A generally axial magnetic field that

has regions of increased intensity at each end

where the magnetic field lines converge. These regions of increased intensity “reflect” charged particles traveling along the field lines back into the

central region of lower magnetic field strength.

Magnetohydrodynamics (MHD): The study of electrically conducting fluids under the influence of

electric and magnetic fields. MHD theory can be

used to provide a good approximation to plasma

behavior in many instances.

Megahertz: One million hertz, or one million cycles

per second. See “Hertz.”

Microinstabilities: See “Fine-scale plasma instabilities.”

Minimum-B mirror: An open magnetic confinement

concept with a magnetic field that is low in strength

in the central region but that gets stronger in all

directions away from the center. Particles in a

minimum-B mirror tend to be “reflected” by the

higher field regions back towards the center. Nevertheless, losses from the minimum-B mirror are too

great for it to be a viable fusion concept by itself.

Minimum load: The power output level below which

a generating plant cannot operate continuously.

Ministerial agreement: An agreement signed by the

secretaries or ministers of the involved departments
App. D—List of Acronyms and Glossary ● 221

or ministries. In the United States, ministerial agreements in fusion are signed by the Secretary of

Energy.

Multilateral agreement: An agreement between three

or more nations.

Neutral beam heating: Heating a confined plasma by

injecting beams of energetic (typically greater than

100 keV) neutral atoms into it. Neutral atoms can

cross magnetic lines of force to enter the plasma,

where they transfer their energy to plasma particles through collisions. In these collisions, the neutral beam particles become ionized, and, like the

other electrically charged plasma particles, are then

confined by the magnetic fields.

Neutron: A basic atomic particle, found in the nucleus

of every atom except the lightest isotope of hydrogen, that has no electrical charge. When bound

within the nucleus of an atom, the neutron is stable. However, a free neutron is unstable and decays with a half-life of about 13 minutes into an

electron, a proton, and a third particle called an

antineutrino. The mass of a free neutron is 1.7 X

10-24 grams.

Neutron flux: A measure of the intensity of neutron

irradiation. It is the number of neutrons passing

through 1 square centimeter of a given target in 1

second.

Neutron irradiation: Exposure to a source of neutrons. Both fission and fusion reactors can provide

neutron irradiation.

Neutron moderator: A material that slows neutrons

down without absorbing them.

Neutron multiplier: A substance that reacts with neutrons to produce additional neutrons.

Neutron wall loading: The energy per unit area per

unit time (or energy flux) carried by neutrons into

the first wall of a fusion reactor. The higher the neutron wall loading, the more rapidly the first wall will

suffer radiation damage, the more radioactivity will

be induced, and the more frequently first wall components will have to be replaced.

Non-ohmically heated plasma: Plasma heated with

auxiliary or external heating.

Nuclear fission: See “Fission. ”

Nuclear fusion: See “Fusion. ”

Nuclear grade: Designation given to components

used in important safety-related systems in nuclear

reactors certifying that the components meet stringent quality control standards,

Nuclear physics: The study of atomic nuclei and nuclear reactions.

Nucleus (nuclei): The central core of an atom, consisting of protons and neutrons, that contains over

99.95 percent of the atom’s mass.

Ohmic heating: Heating that occurs when an electric current is passed through a resistive medium.

Although plasmas are excellent conductors of electricity, they are nevertheless resistive enough to be

heated when they carry large electric currents.

Ohmic heating becomes less efficient as the plasma

gets hotter, and most confinement configurations

therefore require auxiliary (or non-ohmic) heating

to reach ignition.

Open confinement concept: Magnetic configuration

in which the magnetic field lines leave the system.

The magnetic mirror is one example.

Order of magnitude: A factor of 10.

Outage rate: The percentage of time that an electric

generating station is unavailable due to component

failures or other unforeseen conditions that require

the unit to be removed from service.

Overnight construction cost: Total construction cost

of a facility if it could be built instantaneously. Overnight construction cost does not include allowances

for inflation, nor does it include finance charges

such as the interest payments on funds borrowed

to begin construction.

Oxidation chemistry: Study of chemical reactions of

substances with oxygen.

Part-load efficiency: The ratio of the change in efficiency of an electric generating station to the change

in load when the load is decreased from full load

to half.

Particle collisions: A close approach of two or more

particles during which quantities such as energy,

momentum, or charge are exchanged.

Passive protection: Ability to ensure the safety of a

reactor without the use of active safety systems.

Various degrees of passive protection exist. At one

level, the safety of a reactor design might be ensured provided that certain passive systems and

components (e.g., coolant loops or tanks) remained

intact. Before the safety of such a plant could be

demonstrated, it would have to be proven that no

credible accident could interfere with the operation of those passive systems or components. At a

much more stringent level of passive protection,

called “Inherent safety, ” materials properties and

the laws of physics alone would be sufficient to

ensure the safety of the reactor. No assumptions

concerning the integrity of any reactor systems or

components would need to be made. Such an “inherently safe” reactor would remain safe even if

it could somehow be crumpled up into a ball. See

also “Active protection” and “Inherent safely. ”

Personnel exchange: The transfer of personnel between different nation’s programs through visits or

assignments.
222 ● Starpower: The U.S. and the International Quest for Fusion Energy

Plant capital cost: The total cost necessary to bring

the plant to commercial operation. It includes the

costs of items such as engineering and design work,

materials, construction labor, construction management, interest during construction, escalation, sales

tax, equipment, and land.

Plant licensability: How readily a generating technology such as fusion can be expected to receive regulatory approval.

Plant life: The total time a plant can be operated before decommissioning.

Plasma: An ionized gaseous system composed of approximately equal numbers of positively and negatively charged particles and variable numbers of

neutral atoms. The charged particles interact among

themselves, with the neutral particles, and with externally applied electric and magnetic fields. The

plasma state is sometimes called “the fourth state

of matter” due to the fundamental differences i n

behavior between plasmas and solids, liquids, or

neutral gases.

Plasma current: Electrical current flowing within a

plasma. In many confinement schemes, plasma

currents generate part of the confining magnetic

fields.

Plasma exhaust: Particles escaping from the plasma

that are collected by limiters or diverters.

Plasma physics: The study of plasmas.

Plant safety: The capability of the plant to be built

and operated with minimal injury to plant personnel or to the public and minimal damage to property internal or external to the plant.

Plutonium (Pu): An element that fissions easily and

can be used as a nuclear fuel for fission reactors

or fission weapons. Plutonium is not found in nature, but it can be produced by irradiating uranium

with neutrons in a nuclear reactor.

Pneumatic injector: Device that injects fuel pellets

into plasmas at high speed by accelerating them

with compressed gas.

Poloidal direction: On a torus, the poloidal direction

runs around the torus the short way, perpendicular

to the toroidal direction. See “Toroidal direction. ”

Poloidal divertor: A type of divertor. See “Divertor.”

Post-shutdown systems: Systems in a nuclear reactor

that must operate after the reactor is shut down to

ensure that the afterheat does not build up to a level

high enough to damage the reactor or pose a safety

hazard, Such systems would be unnecessary in reactors not generating much afterheat, or ones in

which the afterheat could be removed by purely

passive means.

Power density: The amount of energy generated per

unit time per unit volume of a reactor core; the

power per unit volume.

Project Sherwood: The code-name under which fusion research was secretly conducted in the United

States from 1951 until 1958.

Proliferation: The development of nuclear weapons

by countries not now possessing them. Proliferation

refers primarily to fission-based nuclear weapons.

Prompt fatalities: Deaths due to the immediate effects

of a reactor accident or malfunction. Since deaths

from radiation overdoses are not instantaneous except at extremely high doses, prompt fatalities include those due to radiation overdoses acquired

soon after an accident even if death does not occur immediately. Prompt fatalities do not, however,

include deaths many years later from cancer that

may have been induced by radiation exposure.

Proof-of-concept experiment: Experiment done at a

relatively early stage of development of a confinement concept to determine the limits of plasma stability, explore how the confinement properties

appear to scale, and develop heating, impurity control, and fueling methods. Successful completion

of such an experiment verifies that the confinement

concept appears capable of operating successfully

on a scale much closer to that needed in a reactor.

Proof-of-principle experiment: Experiment one stage

beyond the “proof-of-concept” stage to determine

optimal operating conditions, to establish that the

concept is capable of being scaled to near-reactor

level, to extend methods of heating to high power

levels, and to develop efficient mechanisms for fueling and impurity control.

Protium (H or 1H): The most common isotope of

hydrogen, accounting for over 99 percent of all

hydrogen found in nature. The nucleus of a protium atom is a single proton with no neutrons.

Proton: An elementary particle with a single positive

electrical charge. Protons are constituents of all

atomic nuclei. The atomic number of an atom is

equal to the number of protons in its nucleus.

Pulsed operation: Non-continuous operation of a fusion reactor. This term refers to reactors that must

periodically stop and restart. In pulsed operation,

individual pulses may last as long as hours.

Pumped limiter: A limiter that collects particles at the

plasma edge, allows them to recombine into neutral gas atoms, and pumps the gas out of the vacuum

chamber. A pumped limiter can operate for a

longer period of time than a simple limiter, which

does not remove the collected particles and can

therefore become saturated. See “Limiter.”

Pure fusion reactor: Reactor that generates all its

energy from fusion reactions in the plasma and

tritium-breeding reactions in the blanket. A pure

fusion reactor is distinguished from a fission/fusion

hybrid reactor, which either generates energy or
App. D—List of Acronyms and Glossary ● 223

produces fissionable fuel by including fertile or fissile material in the reactor blanket. See “Fission/fusion hybrid. ”

Quality of confinement: See “Confinement parameter. ”

Radiation: The emission of particles or energy from

atomic or nuclear processes. Radiation is also

sometimes used as a shorthand for “electromagnetic radiation, ” which refers specifically to emitted energy and does not include particles.

Radiation dose: A general term denoting the quantity of radiation absorbed.

Radiation exposure: The amount of radiation passing through a particular target.

Radiative cooling: Loss of heat from a system through

electromagnetic radiation. Since electromagnetic

radiation carries energy away, a system that radiates will cool down.

Radioactive inventory: The total amount of radioactive material present.

Radioactive material: A material of which one or

more constituents exhibits radioactivity.

Radioactivity: The inherent property of the nuclei of

unstable isotopes to spontaneously emit particles

or energy and transform to other nuclei. Such radioactive isotopes can be either natural (e.g., carbon14, which is produced by cosmic rays interacting

with the earth’s atmosphere) or manmade (e.g.,

plutonium).

Radiofrequency power: Electromagentic radiation

having frequencies in the radio or microwave portions of the electromagnetic spectrum and extending up to the infrared band.

Radiofrequency (RF) heating: Heating a plasma by

depositing radiofrequency power in it. Only radiation at certain specific frequencies—e.g., the electron cyclotron frequency or the ion cyclotron

frequency–will be absorbed by the plasma. See

“Electron cyclotron resonance heating” or “Ion cyclotron resonance heating. ”

Radioisotope: A radioactive isotope; in particular, a

radioactive isotope of a substance whose naturally

occurring isotopes are not radioactive.

Reactive: Able to participate easily in chemical or nuclear reactions.

Reactor potential: A qualitative description of a fusion confinement concept denoting how easy it

would be to design, build, operate, and maintain

a fusion reactor based on that concept, as well as

how acceptable such a reactor’s environmental, social, economic, and safety characteristics would be.

Reactor-scale experiment: Experiment to test a confinement concept by generating a plasma equivalent to that needed in a full-scale reactor. Such an

experiment must achieve reactor-level values of

beta and must demonstrate temperature, density,

and confinement times sufficient for the production of net fusion power. Furthermore, its heating,

fueling, and other technologies must also be able

to support a reactor-level plasma.

Rem: A measure of the effect of radiation on biological systems (acronym for Roentgen equivalent man).

Different types of radiation (e.g., alpha particles,

beta particles, neutrons, and gamma rays) have

different biological effects. Therefore, doses are corrected by a different factor for each type of radiation to convert them into reins. One rem of any

type of ionizing radiation produces the same biological effect as one Roentgen of ordinary x-rays.

Remote maintenance: Conducting maintenance on

reactor systems or components by remote control,

rather than “hands-on. ” Remote maintenance will

be required in fusion reactors and in many future

fusion experiments because the radioactivity levels

near and inside the plasma chamber will be too

high to permit human access.

Resistance: The difficulty with which an electric current passes through a material. For a given amount

of electric current, the higher the resistance, the

more electrical energy will be dissipated as heat.

Reversed-field pinch: A closed magnetic confinement

concept having toroidal and poloidal magnetic

fields that are approximately equal in strength, and

in which the direction of the toroidal field at the

outside of the plasma is opposite from the direction at the plasma center.

Roentgen: A measure of radiation intensity.

Routine release: Releases that occur as a result of normal, or routine, plant operation.

Runaway reaction: A reaction whose rate increases

as the power level rises, In such a reaction, any rise

in output power increases the reaction rate, boosting the output power still further, and so on. Such

a reaction is unstable, growing larger and larger until some other mechanism—e.g., exhaustion of

fuel–limits the reaction power.

Scaling: Extension of results or predictions measured

or calculated under one set of experimental conditions to another situation having different conditions. One of the most important functions of a

confinement experiment is to determine how confinement properties scale with parameters such as

device size, magnetic field, plasma current, temperature, and density. It is important to understand

the scaling properties of a confinement concept—

either empirically or theoretically—to assure that

future experiments have a reasonable probability

of succeeding.
224 . Starpower: The U.S. and the International Quest for Fusion Energy

Scaling relationship: The trend in behavior of a parameter as other parameters are varied. See “Scaling.”

Scientific feasibility: The successful completion of experiments that produce high-gain or ignited fusion

reactions in the laboratory using a confinement

configuration that lends itself to development into

a net power producing system.

Self-regulating: A system which, when disturbed in

some way, will respond in a manner that tends to

compensate for the disturbance. A self-regulating

reaction would be the opposite of a runaway one;

if the reaction power level were to increase, the

system would respond by lowering the reaction

rate, permitting the power level to drop back down

again. Such a system is also called “stable. See also

“Runaway reaction” and “instabilities.”

Shield: A structure interposed between reactor components, such as magnetic field coils, and the fusion plasma to protect the components from the

flux of energetic particles produced in the plasma.

Simple magnetic mirror: A magnetic field consisting

of a cylinder filled with an axial magnetic field of

relatively constant strength, with regions of stronger

magnetic field at each end. The stronger field regions tend to “reflect” plasma particles back into

the cylinder. However, too many particles nevertheless escape out the ends of the cylinder for the

simple mirror to be a viable fusion concept.

Volubility: Ease with which a substance dissolves in

another substance.

Spheromak: A magnetic confinement concept in

which a large fraction of the confining magnetic

fields are generated by currents within the plasma.

The spheromak is a form of compact toroid.

Spin: An inherent property possessed by subatomic

particles analagous to the rotation of the earth. Just

as the spin axis of the earth points towards the

North star, the spin axis of a subatomic particle

points in some direction. The spin axis of a subatomic particle can be oriented in a particular direction by use of a magnetic field.

Spin polarization: Preparation of many particles, such

as deuterium and tritium nuclei, so that their spins

point in the same direction. If the spins of deuterium and tritium are polarized, the D-T reaction

rate is enhanced.

Spin-offs: The secondary, or auxiliary, benefits of

high-technology research and development programs in applications other than those which are

the primary motivation for research.

Steady-state operation: Continuous operation, without repeated starting and stopping.

Steam generator and turbine: In an electric generating station, the steam generator uses the heat produced by the power source to boil water into

steam, which is passed through a turbine to turn

an electrical generator.

Stellarator: A toroidal magnetic confinement device

in which the confining magnetic fields are generated entirely by external magnets.

Superconductivity: The total absence of electrical resistance in certain materials under certain conditions. Until recently, superconductivity had only

been found to occur in certain materials cooled to

within a few degrees of absolute zero. Since late

1986, however, a new class of materials has been

discovered that become superconducting at temperatures far higher than the materials previously

known. An electrical current that is established in

a superconducting material will persist as long as

the material remains below its critical temperature.

See “Critical temperature.”

System studies: Studies presenting preconceptual designs for fusion reactors that serve to uncover potential problems and determine how changes in design choices affect reactor characteristics. System

studies are particularly valuable in guiding the

reseach program by identifying areas where further

research and development can have the greatest

impact.

Tandem mirror: Type of open magnetic confinement

configuration in which both ends of a simple magnetic mirror, called the central cell, are plugged by

end cells to improve confinement. Each end cell

is itself a magnetic mirror that generates an electric field to prevent particles in the central cell from

escaping, See “Central cell” and “End cell. ”

Technological feasibility: In this report, acquisition

of both sufficient scientific understanding and sufficient engineering and technological capability to

design and build a fusion reactor; attainment of

both scientific feasibility and engineering feasibility.

Temperature: A measure of the average energy of a

system of particles. Given sufficient time and enough

interaction among the different portions of any system, all portions will eventually come to the same

temperature. In short-lived plasmas, however, the

ion and electron temperatures usually differ because of insufficient interaction between the two.

Plasma temperatures are measured in units of electron volts, with 1 electron volt equal to 11,6050 K.

Thermal instability: Potential instability in a burning

plasma arising from the fact that the fusion reaction

rate increases strongly with temperature. It is not

yet known to what extent burning (ignited) plasmas

will be subject to this instability, or whether other,

self-regulating aspects of plasma behavior will predominate. See “Runaway reaction.”
App. D—List of Acronyms and Glossary ● 225

Thermonuclear fusion: See “Fusion. ” “Thermonuclear” refers to the extreme temperatures required

for the fusion process to take place.

Thermonuclear weapons: Nuclear weapons utilizing

the fusion process, also called hydrogen bombs.

Thermonuclear weapons are very large-scale examples of the inertial confinement approach to fusion.

Theta pinch: A pulsed device in which a fast-rising,

strong (100 kilogauss) magnetic field compresses

and heats a plasma column in a few microseconds.

The magnetic field is parallel to the axis of a plasma

column.

Tokamak: A magnetic confinement concept whose

principal confining magnetic field, generated by external magnets, is in the toroidal direction but that

also contains a poloidal magnetic field that is generated by electric currents running within the

plasma. The tokamak is by far the most developed

magnetic confinement concept. See also “Conventional tokamak” or “Advanced tokamak.”

Toroidal direction: On a torus, the toroidal direction

runs around the torus the long way, in the direction that the tread runs around a tire. More generally, “toroidal” refers to devices in the shape of a

torus.

Torus: The shape of a doughnut, automobile tire, and

inner tube.

Transformer: Device in which a changing electrical

current in one electrical conductor generates a

changing magnetic field, which in turn induces

electrical current in a second conductor. The plasma

current in a conventional tokamak is established

by a transformer in which one of the conductors

is a set of coiIs located in the hole in the center

of the plasma torus and the second conductor is

the plasma itself.

Treaty: The highest level of formality for an international agreement. Treaties involving the United

States must be ratified by a two-thirds majority of

the U.S. Senate.

Tritium (T or 3H): A radioisotope of hydrogen that has

one proton and two neutrons in its nucleus. Tritium

occurs only rarely in nature; it is radioactive and

has a half-life of 12.3 years. In combination with

deuterium, tritium is the most reactive fusion fuel.

Tritium breeding: Production of tritium in the blanket of a fusion reactor by irradiating lithium nuclei

with fusion-produced neutrons. Lithium nuclei undergo nuclear reactions with neutrons that yield

tritium nuclei and alpha particles.

Turbulence: Random or chaotic flow of a fluid, such

as that of water in the rapids of a river.

Umbrella agreement: General agreement between

nations establishing a willingness to cooperate in

a specific subject area and outlining general procedures, but not specifying particuIar activities or

terms.

Unit rating: The electrical capacity of a generating

station.

Uranium (U): A very heavy, radioactive element

found in nature that can be used as nuclear fuel.

Two uranium isotopes are important in nuclear

energy: uranium-235 can undergo nuclear fission,

and uranium-238, the most plentiful isotope, can

be used to produce plutonium.

Waste handling and disposal: The in-plant handling,

on-site disposal (or transportation), and off-site disposal of waste materials formed as byproducts of

the energy production processes.
Index
Index

Accidents, risk and severity of fusion reactor, 17-18,

106-108

Acid deposition, 29, 119

Advanced fuel cycles

concepts for, 90-92, 116

reactor safety, radioactive waste production, and, 18,

108, 109-110

Advanced Toroidal Facility (ATF), 142, 60, 143

Afterheat, 18, 106, 110, 1 1 1

Agreements

major international, 158-163, 158

types of international cooperative, 157-158, 157

Alcator project, 146, 23, 147

American Physical Society, 131

Argonne National Laboratory, 93

Atomic Energy Act of 1954, 40

Atomic Energy Commission (AEC), 8, 9, 40-44

Auburn University, 147

Austria, 159, 184, 185

Axisymmetric Divertor Experiment (ASDEX), 71, 159, 72

Balance of plant, systems in, 12, 72, 73, 73

Beta parameter, scientific progress in improving, 70-71,

80-81, 92, 94

Bilateral agreements

Japan-European Community, 182

United States-European Community, 163

United States-Japan, 161-163

United States-U.S.S.R., 163

Blanket

development program, 97-98

function and development of fusion reactor, 81-84

radioactivity of, 109

Breakeven

confinement time required for, 33

experiments, 9, 46

scientific progress in attaining, 68-70

Breeder reactors, 18, 44, 46

DOE deemphasization of, 48

weapons grade materials produced by, 112

See also Fission/fusion hybrid reactors

Breeding ratio, 82, 84

Budget, Bureau of the, 44

Bureau of Mines, U. S., 113

California, 21, 41, 141, 148

wind energy use in, 123

Canada, 172

Carbon dioxide (CO2 ), accumulation from fossil fuel

use, 5, 29, 119, 120-121

Carter, Jimmy, DOE creation by, 9, 48

Chernobyl (U.S.S.R.), 107, 121

Climate, CO2 effects on, 5, 29, 112, 119, 120-121

Closed confinement concepts, 58-63

See also Confinement

Coal

domestic reserves of, 19, 119

technologies, 119-120

See also Fossil fuels

Collaboration

applicability of existing projects to future fusion,

170-173, 173

benefits and risks of, 25, 164, 166, 190

costs of international, 25, 164-165, 193, 194

international, on fusion facility construction and

operation, 10, 15, 24-25, 156, 158-163, 183-185

management approaches to, 170-173

obstacles to, 25-26, 166-170, 194

prospects for, 24-25, 182-185

report’s definition of, 156

See also Cooperation

Colleges. See Universities

Commercialization

fusion power, 5, 8, 15-16, 19, 30, 101, 116-119,

123-125, 150-151, 189, 190, 192, 193, 195, 197,

99, 100

public urgency for, 3, 19-20, 124, 125

transition in responsibility and, 23, 150-151

Compact Ignition Tokamak (CIT)

funding for, 95-97

operation of, 190, 197

preliminary design of, 96

recommended construction and costs of, 13, 52-53,

138-139

Compact toroids, 61-63

Comprehensive Program Management Plan of 1983

(CPMP), 51

Compression heating, 74, 76

Confinement

concepts, 8, 11-13, 34-35, 47-48, 57-65, 12, 57

conclusions concerning approaches to, 65-66

future issues involving, 94-95

interrelationship with temperature, 33, 70

plasma parameters achieved by various concepts of,

69

Confinement parameters. See Lawson parameters

Confinement Physics Research Facility (CPRF), 61

Congress, U.S.

AEC abolishment by, 9

energy supply concern in, 47

fusion power development and, 35-36, 44

MFEE Act, passed by, 9, 51

Cooperation

administrative issues and international, 169-170

incentives for, 24, 25, 155, 164-166

international, in fusion R&D, 3, 6, 9, 14, 15, 24-26,

44, 63, 66, 139, 155-186

obstacles to international, 25-26, 166-170

possible areas for international, 182-183

report conclusions on international, 185-186

229
230 . Starpower: The U.S. and the International Quest for Fusion Energy

report’s definition of, 156

types of, and levels of agreement, 156-158, 157

See a/so Collaboration

Coordinating Committee (COCOM), 166

Cornell University, 147

costs

blanket design and reactor, 83

CIT, 13, 52-53, 138-139

difficulty in estimating future reactor, 113-116

engineering test reactor, 98, 99, 114, 190

of first wall/blanket test program, 97

of fusion reactors, 113-116, 190

fusion’s commercial acceptance and electricity,

117-118

future fusion research, 15, 26,99-101, 113-116, 155,

156, 190, 191, 192, 193, 194, 195, 197

long-term burn device, 97, 98

magnetic confinement systems development, 94-95,

96, 97, 190, 191, 192, 193, 194, 195, 197

of materials irradiation test facilities, 97

near-term fusion research, 21-22, 134-139, 22, 134,

135, 136, 137, 138, 139

of nuclear-technology study device, 98

superconducting magnets effect on reactor, 85, 86,

96, 115

See also Economics; Funding

Critical temperature, 85, 86

D-D fusion reaction, 31, 92

D-T fusion reaction, 32

accident risk from, 17-18, 106-108

breakeven experiments using, 9, 46

in dense z-pinch confinement, 64

disadvantages of, 91

energy released from, 6, 31

plasma heating from, 74-75

remote maintenance for, experiments, 88, 90

See also Fuel

D-T fusion reactors

opposition to constructing, 46-47

principal locations of potential hazardous agents in,

109

See also Reactors

D -

3He fuel cycle, 91-92, 116, 91

See also Advanced fuel cycles; Fuel

Decay heat. See Afterheat

Defense

applications of fusion research, 35, 39-40, 133

concerns about international collaboration{ 26, 164,

166-167

plasma physicists working in, 21, 132

Dense z-pinch, 64-65, 66, 65

Density, plasma, and confinement time, 33-34

Department of Defense (DoD), 21, 133, 140

Department of Energy (DOE)

fusion development policy, 3, 13, 14, 16, 23, 24, 26,

30, 48-50, 52, 53, 93-94, 105

fusion research management by, 9, 40, 48-52

international activities in fusion cooperation report by,

192-193

magnetic field exposure guidelines of, 108-109

National laboratories, 21, 41, 140-143, 1 4 1

Office of Energy Research, 48

Office of Fusion Energy, 21, 23, 93, 132

plasma physics funding by, 20, 131-132, 132

Tritium Systems Test Assembly operation by, 88

Department of Health and Human Services (DHHS),

135

Deuterium (D)

in fusion reactions, 6, 30-31, 113

supply of, 19, 113

See a/so D-T reaction; Fuel; Hydrogen

Development

alternate paths for concept, 66-67, 67

classification of confinement concepts by level of, 12,

57

plasma physics, 20, 31-33, 39, 131-132

technical issues in fusion, 94-98, 189-191

Diverters, 80, 93

Division of Plasma Physics of the American Physical

Society, 131

Doublet Ill (D Ill) tokamak

international cooperation on,

management of, 171-172

Doublet II I-D (D III-D) tokamak,

162

Economics

62-163

59, 71, 148, 15, 75,

of international cooperation on fusion research, 3-4,

15, 24, 25, 26, 155, 164-166

of nuclear fission power, 121-122

renewable energy source, 123

safety assurance levels and fusion reactor, 115

See a/so Costs, Funding

Education, fusion program’s benefits to, 20, 132, 140

Efficiency

energy, 119, 120, 121, 190, 192

energy conversion, 96, 116

plasma current generation, 79

Electric Power Research Institute (EPRI), 48

fusion acceptance poll by, 118, 118

fusion research by, 149

Electricity

comparison of prospective long-range, supply options,

123, 124

production as long-term fusion research goal, 8, 16,

30, 105

systems in a fusion station generating, 12, 72, 13, 72

Energy

advantages of fusion power as source of, 3, 19, 29-30,

113, 117, 118, 123, 124

availability of fusion, 116-117

conversion by fusion blanket, 81-82

demand and fusion development, 19-20, 124, 125

desirability of fusion, 117-119

direct, conversion techniques, 92, 116

feasibility of fusion as a source of, 5, 8, 15-16, 30,

116-117, 123-125

Federal funding of non-fusion, R&D, 134-139, 138

fusion as an, program, 16-20, 31, 105-128
Index ● 2 3 1

fusion’s context, 19-20, 125, 190

loss mechanisms in plasma heating, 74, 76

near-term benefits of fusion, program, 20, 133, 190

projections of global primary consumption of, 125,

126

released by D-T reaction, 6, 31

renewable sources of, 9, 47, 122-123

source problems, as incentive for fusion development,

5-6, 9, 17-18, 19-20, 29-30, 192, 193, 195-196, 197

See a/so individual sources of

Energy gain (Q), 67-68

Energy Research Advisory Board (ERAB), 119

fusion program review by, 50, 51-2, 52-53

industry representatives on, 148

international cooperation panel of, 168

Energy Research and Development Administration

(ERDA), 9, 40, 47, 50

Engineering test reactor (ETR), 9, 47, 139

costs of, 98, 99, 114, 190

See also International Thermonuclear Experimental

Reactor (ITER)

England. See United Kingdom (U. K.)

Environment

fossil fuel’s pollution of, 5, 29, 119-121

fusion reactors’ effects on, 5, 18, 29-30, 31, 81, 83,

109-112, 110, 111

Environmental Protection Agency (EPA), 135

ESECOM report, 106

levels of safety assurance derived from, 107-108

radioactive waste hazard and, 109-110

reactor costs examined in, 115

Europe. See European Community (EC)

European Atomic Energy Community, 159

European Community (EC)

ETR plans of, 98

fusion goals of, 29, 180

fusion program status by, 16, 48

fusion research in, 60, 61, 62, 63, 86

international cooperation by, 140, 158, 159, 160-161,

163, 170-171, 172-173, 180, 189

JET development by, 158, 160-161

See a/so individual countries of

European Laboratory for Nuclear Research (CERN), 172

European Space Agency, 172

Facilities

cost of fusion research, 138-139, 190-191, 139

development of future fusion research, 12-15, 94-98,

138-139, 190-191

joint construction and operation of, 24-25, 156

siting fusion, 26, 115, 160, 168

See also Reactors; individual facilities

Field-reversed configuration (FRC), 62, 74, 63

FINESSE study, 97, 98

First wall. See Blanket

Fission/fusion hybrid reactors, 16, 19, 105, 112, 114,

202

See a/so Breeder reactors

Fission reactors, safety of, 18-19, 106

Fossil fuels, 5, 29, 119-121

See a/so Coal; Natural gas; Oil

France, 86, 184

See a/so European Community (EC)

Fuel

advanced fusion, cycles, 18, 90-92, 108, 109-110,

116, 91

fission reactor, supply, 122

injection of, 18, 76-79, 106, 78

production of, from fusion reactors, 16, 81, 82-83, 84,

85, 88, 91, 105, 112, 181

supply of, for fusion reactors, 5, 19, 113

See also individual fuel types

Funding

D Ill-D, 162-163

European Community fusion program, 161

Federal, of non-energy R&D, 134-139, 134, 135, 136,

137

Federal, plasma physics, 20, 131-132, 132

magnetic fusion research, 3-4, 9-10, 12-13, 15, 21-22,

23, 26, 30, 40, 44, 46, 47, 48-51, 95, 121-122,

134-139, 4, 5, 22, 41, 42, 134, 138, 139, 141

See a/so Costs; Economics

Fusion Engineering Design Center, 142

Fusion Engineering Device (FED), 50

Fusion Experimental Reactor (FER), 182

Fusion power core systems, 12, 48, 72, 73, 74-90, 14,

73

Fusion self-heating, 74, 76

Fusion Working Group, 184

GA Technologies, Inc., fusion research by, 59, 61, 71,

148, 149{ 162-163

General Atomic Corp., 41, 144

General Electric Co. (GE), 41, 44

Geneva Summit of 1985, 179, 181, 184

Georgia Institute of Technology, 147

Germany, Federal Republic of, 63, 71, 159

See a/so European Community (EC)

Gorbachev, M., 179, 181, 184

Gravitational confinement, 34

Hawaii, 123

Helium, 31

High energy gain, 8, 30

Hiroshima University, 163

Hitachi Corp. 149

H-mode scaling, 93

Hydrogen

as fuel in fusion reaction, 6, 9, 17-18, 29, 30-31, 46,

64, 74-75, 88, 90, 91, 106-108

isotopes of, 30-31

See also Deuterium; Tritium

Ignition

confinement time required for, 33

research, 13, 95-97

scientific progress in reaching, 68, 69, 94

sustainability of fusion reaction when reaching, 8, 30

See a/so Plasma
— —

232 ● Starpower: The U.S. and the International Quest for Fusion Energy

Incentives

fossil fuel curtailment, 121

for fusion development, 5-6, 9, 17-18, 19-20, 29-30,

117-118

Industry

base for fusion, 118, 150-151

competitiveness of United States, 164, 167-168

fusion research involvement by, 6, 22-23, 41, 44, 51,

147-151, 22, 134, 138, 147

fusion research “spin-offs” used in, 133

plasma physicists in, 132

See a/so Private sector

Inertial confinement, 35, 205-207, 206

Institute for Plasma Physics, 159

Integrated Fusion Facility (IFF), 116

International Atomic Energy Agency (IAEA), cooperation

facilitation by, 158-159, 185

International Energy Agency (IEA), cooperation

facilitation by, 159-160, 163, 171

International Fusion Superconducting Magnet Test

Facility, 159, 89, 160

International Thermonuclear Experimental Reactor

(ITER)

collaboration in design of, 98

potential for collaboration on, 179-185

proposed development of, 14, 26, 53, 183-185

siting decision for, 168

status of, 184-185

See also Engineering test reactor

International Tokamak Reactor (lNTOR), 159

management of, 170, 184-185

Issues

fusion power core system, 75, 77-79, 80, 81, 83-84,

85, 86-88

technical, in fusion development, 94-98, 189-191

Japan

ETR plans of, 98

fusion goals of, 29, 182

fusion program status is, 16, 48

fusion research in, 60, 61, 62, 63, 64, 86

international cooperation by, 159, 161-163, 172-173,

181-182, 184

role of industry in fusion development in, 149

Japan Atomic Energy Research Institute (JAERI), 149,

159

Joint European Torus (JET), 16, 48, 158, 160-161, 163,

180, 15, 161

costs of, 95

management of 170-171

shielding use in, 85

Joint Institute for Fusion Theory (JIFT), 163

JT-60 Tokamak (Japan), 16, 48, 17, 183

cost of, 95

KMS Fusion, Inc.

inertial confinement fusion research at, 207

Large Coil Task (LCT), 86, 159

management of, 171

Large Helical System, 60

Lawrence Berkeley Laboratory

inertial confinement fusion research at, 207

Lawrence Livermore National Laboratory (LLNL)

fusion research at, 21, 41, 48, 64, 86, 141

inertial confinement fusion research at, 207

See also National laboratories; Research

Lawson parameters, 34, 42

of advanced fuels, 91

magnets obtaining high, 93

TFTR-achieved, 52

increase in, due to tokamaks, 44, 45

Licensing. See Regulation

Lithium

supply, 19

tritium breeding and, 82-83, 84, 113

Los Alamos National Laboratory (LANL)

fusion research at, 21, 41, 48, 61, 62, 65, 88, 142-143

inertial confinement fusion research at, 207

See also National laboratories; Research

Macrotor, 146

Magnetic confinement, 11-12, 34

status and comparison of international, programs, 16,

48, 155, 174-178, 174, 175, 176, 177, 178

See also Confinement

Magnetic fields

in closed confinement configurations, 58-59, 58

motion of charged particles in, 34, 63, 34

potential hazards from, 108-109, 109

use of, for plasma confinement, 11-12, 34, 47-48,

57-66, 12, 57

Magnetic field utilizaiton factor. See Beta parameter

Magnetic Fusion Advisory Committee (MFAC)

CIT review by, 96, 97

industrial participation in fusion findings by, 149, 150

industry representatives on, 148

university research funding by, 145

Magnetic Fusion Energy Computing Center (MFECC

Act), 133, 141

Magnetic Fusion Energy Engineering Act of 1980 (MFEE

Act), 9, 50-51, 191

Magnetic Fusion Engineering Center, proposed creation

of, 5 0

Magnetic Fusion Program Plan, 1985 (MFPP), 10, 52

Magnetic mirrors, design and development of, 48, 50,

63-64, 64

Magnets

function and development of fusion reactor, 85-88,

115-116

See also Magnetic fields

Maintenance, remote, for fusion reactors, 88-90

Manhattan Project, 39

Massachusetts Institute of Technology (MIT), 64, 146,

147

Materials

and neutron irradiation, 183

development for fusion reactors, 84, 97

production in fusion reactors, 203

requirements for fusion reactors, 19, 113

superconducting, 84, 85, 86-88, 96, 115
Index . 233

testing, 97

McCormack, Mike, 50

MFTF-B, 48, 64, 141, 49, 87

COSt Of, 138

superconducting magnets in, 86

Military. See Defense

Mirror Fusion Test Facility-B. See MFTF-B

Mitsubishi Corp., 149

Mitterand, F., 184

Model C Stellarator, 46, 10, 4 5

Modeling

global energy demand, 125, 126

fusion generating stations, 105

fusion scaling relationship, 58, 71-72

See a/so System studies

Monitoring

reactor blanket modification, 112

tritium processing, 88

Multilateral agreements

international, 158-161

See a/so Cooperation; Collaboration

Muon-catalysis, approach to fusion, 207-208

National Academy of Sciences

fusion personnel estimates by, 140

physics research review by, 39

See a/so National Research Council

National Aeronautics and Space Administration (NASA),

133, 135

National Committee on Radiation Protection and

Measurements, 109

National Institutes of Health (NIH), 135

National laboratories

fusion R&D conducted by, 21, 41, 140-143

General Atomics as, 44

personnel in, 21, 132, 140

See a/so Facilities; individual laboratories

National Research Council

fission/fusion hybrid reactors, report by, 114

international cooperation report by, 156, 165

plasma physics report by, 132

See a/so National Academy of Sciences

National Science Foundation (NSF)

general science research by, 135

plasma physics funding by, 132

National security. See Defense

Natural gas, 120

Naval Research Laboratory, 62, 65

inertial confinement fusion research at, 207

Neutral beams

injecting, to generate current, 79

plasma fueling using, 76

plasmas heated with, 68-70, 74, 75, 93

New Jersey, 21, 41, 140

New Mexico, 39

Next European Torus (NET), 170, 180

Nixon, Richard M., 47, 163

Nixon-Brezhnev Accord, 163

Nuclear Regulatory Commission, U.S. (NRC), 110, 135

Oak Ridge National Laboratory (ORNL)

magnetic fusion research by, 21, 41, 46, 48, 142

materials needs study by, 113

pellet fueling technology development by, 77

See a/so National laboratories

Office of Fusion Energy (OFE)

research by, 21, 23, 132

Technical Planning Activity coordination by, 93

Office of Technology Assessment (OTA)

fusion energy context workshop by, 36, 123

issues in international cooperation workshop by, 36,

166

objectives of fusion assessment by, 35-36

report findings of, 4-6

selected studies examining other energy technologies

by, 119

Ohmic heating, 61, 74, 148-149

Ohmically Heated Toroidal Experiment (OHTE), 61,

148-149, 24, 149

Oil, 120

See a/so Fossil fuels

Open confinement concepts, 63-65

See a/so Confinement

Operational Test Reactor (OTR), 181

Pennsylvania State University, 147

Perhapsatron, 9, 43

Personnel

international exchange by, 156, 159, 161, 163

magnetic fusion, 21, 139-140

Petroleum, 120

See a/so Fossil fuels

Phaedrus, 64, 146

Phillips Petroleum Co., 148

Physics, 35, 147

plasma, 10, 20, 31-33, 39, 46, 131-132, 197

Plasma

behavior of burning, 95-97

burn control, 80-81

confinement concepts, 8, 11-12, 34-35, 47-48, 57-66

current generation, 79

definition of, 8, 31-33, 33

energy loss mechanisms, 74, 76

fueling, 76-79, 78

heating, 69, 74-76, 77

instabilities in, behavior, 11, 33, 42, 44, 57, 64, 68,

76, 80-81

reaction product control, 79, 80

research, 44, 59, 93

See a/so Magnetic fields

Plasma physics

advances in, 10, 20, 31-33, 39, 46, 131-132, 197

Federal funding of, 20, 131-132, 132

Plutonium, 40

breeding in nuclear reactors, 112

declassification of, generation technology, 43

Policy

fusion energy promotion, 117

Japan’s energy, 29, 182
234 “ Starpower: The U.S. and the International Quest for Fusion Energy

U.S. fusion development, 3-4, 14, 23, 24, 26, 48-50,

52, 53, 93-101, 127-128, 182-185, 189-197

world fusion development, 29, 99, 101, 127-128,

179-185

Politics

D-T experiment’s effect on, 46

international cooperation and, 25, 26, 160, 163, 165,

181

Princeton Beta Experiment (PBX), 71

Princeton Beta Experiment Modification (PBX-M), 59, 71

Princeton Large Torus, 77

Princeton Plasma Physics Laboratory (PPPL), 142

CIT facility at, 53, 138-139

fusion research at, 21, 41, 59, 62, 70-71, 95-97, 140

spin polarization research at, 90-91

TFTR construction at, 47, 49

See a/so National laboratories

Princeton University, 140

Private sector

fusion research involvement in, 6, 21, 22-23, 41, 44,

51, 117, 147-151, 22, 134, 138, 147

plasma physicists in, 132

See also Industry

Process heat, production by fusion, 203

Project Sherwood, 8, 40-42

declassification of, 42-44

Protium. See Hydrogen

Public opinion

on fusion power acceptability and development, 3, 8,

9, 30, 46, 202

on nuclear fission power, 121, 122

Pumped limiters, 80

Q. See Energy gain

Radiation

damage to blanket materials, 83

routine emissions from fusion reactors of, 111-112

Radioactive waste, fusion reactor, 18, 29-30, 83,

109-110, 110

Radiofrequency (RF)

heating, 74, 75-76, 93

injecting, power to generate current, 79

Reaction

requirements for fusion, 6-8, 29, 30, 31-35, 7, 32

runaway, 18, 106

Reactor potential, 66

Reactor relevance, 48, 50

energy gain as measure of, 67-68

Reactors

blanket design’s influence on, 83

breeder, 19, 44, 46, 48, 112

characteristics of fusion, 16-20, 105-106, 127

confinement concept requirements for viable fusion,

66

development of, 8, 9, 12, 46, 47, 48, 49, 51, 52, 53,

72-73, 139

fusion test, 9, 14, 26, 47, 53, 98, 168, 179-185

nuclear weapon proliferation potential of fusion,

18-19, 48, 112, 122

routine emissions from fusion, 111-112

shutdown and emergency cooling systems of, 18, 106

See a/so Facilities, individual types of

Reagan, Ronald, energy policy of, 51, 136, 179, 181,

184

Regulation

fusion power, 8, 16, 30, 117, 118, 1 18

impact of reactor cost of, 114, 115, 116

Renewable energy sources, 9, 47, 122-123

Rensselaer Polytechnic Institute, 147

Research

advanced fuel, 90-92

causes of growth in fusion, 9, 46

closed confinement concept, 48, 59, 60, 61, 62-63

cost of, facilities, 138-139, 190-191, 139

costs of fusion, 15, 99-101, 113-116, 155, 156, 190,

191, 192, 193, 194, 195, 197

declassification of fusion, 9, 42-44, 155

defense-related fusion, 35, 39-40

funding fusion, 3-4, 9-10, 12-13, 15, 21-22, 23, 26, 30,

40, 44, 46, 47, 48-51, 95, 134-394, 5, 22, 41/ 42

goal of current fusion, 8, 16, 30, 105

history of magnetic confinement fusion, 8-10, 39-53

ignited plasma, 13, 52

inertial confinement, 35, 205-207

international cooperation in fusion, 3, 6, 9, 14, 15,

24-26, 44, 53, 155-186, 193-194

issues affecting future fusion, policy, 24-26, 94-98,

189-191

on magnetic fields’ safety risk, 108-109

materials, 157

muon-catalysis, 207-208

near-term benefits from fusion, 6, 20, 131-134, 191

nuclear fission technology, 122

open confinement concept, 64

participants in magnetic fusion, 21-23, 29, 40-41,

140-151

plasma heating, 75-76, 93

plasma physics, 59, 197

progress and future directions in fusion, 9, 48-50,

93-101, 189-197

superconducting materials, 86-88

Research and development (R&D) See. Development;

Research

Reversed-field pinch, 60-61, 78, 79, 61

Safety

assurance levels, 107-108, 115

fission reactor, 121

fusion reactor, 5, 17-18, 30, 31, 81, 93, 106-108

occupational, on fusion reactor site, 108-109, 109

shielding and personnel, 85

tritium processing, 88

Sandia National Laboratory

inertial confinement fusion research at, 207

Scaling, 58, 71-72
Index ● 2 3 5

H-mode, 93

Schedule, future fusion R&D, 3-4, 15-16, 98-99,

116-117, 127-128, 190, 194, 196, 99, 100

Science. See Research; Technologies

Second Geneva Conference on the Peaceful Uses of

Atomic Energy, 44

Self-reference, 235

Senior Committee on Economics, Safety, and

Environmental aspects of magnetic fusion energy.

See ESECOM report

Shielding

radioactivity of, 109

reactor, 84-85

Siting, facilities, 26, 115, 160, 168

Soviet Union

ETR plans of, 98

fusion goals of, 29, 180-181

fusion research in, 16, 48, 60, 62, 63, 64, 86

international cooperation by, 159, 163, 180-181, 184

plasma confinement breakthrough by, 9, 44-46, 59

Space station, proposed management of, 172-173

Special Nuclear Materials, Atomic Energy Act’s

definition of, 40

Spectra Technologies, 62

Spheromak, 61, 78, 79, 62

Spin polarization, 90-91

STARFIRE, 115

as reference base for ESECOM report, 108, 110, 110,

111

Stellarator, 59-60, 60

conversion of, into tokamak, 46, 59

international cooperation on, 159

Strategic Defense Initiative (SDI), 21, 133, 140, 167

Superconducting materials

recent advances in, 86-88

use in magnet coils, 84, 85, 86, 88, 96, 115

Swiss Institute for Nuclear Research, 159

Synthetic fuels, production by fusion, 203

System studies, 12, 48

on fusion-generated electricity costs, 114

generating stations, 105

See a/so Modeling

Tandem Mirror Experiment (TMX), 48

Tandem Mirror Experiment Upgrade (TMX-U), 48, 64,

91

Tandem mirrors, 63-64, 65, 141, 64

TARA device, 64, 147

Technical Planning Activity (TPA), 93-95, 97, 98-101,

116

Technologies

advances in fusion, 72-73, 93, 97-98

declassification of nuclear, 43-44

fossil fuel, 119-121

fusion energy competitiveness with other energy,

19-20, 105, 119-126

magnetic fusion research “spin -off,’ 6, 20, 22, 44,

132-133

nuclear fission, 43-44, 121-122

pellet fueling, 76-79, 93, 78

plasma heating, 74-76, 93

reactor-relevant, 48, 50

renewable energy, 9, 47, 122-123

transfer of, 24, 25, 26, 158

Temperature, fusion reactions and, 6-8, 31-33, 42, 69,

70

Tennessee, 21, 41, 142

Testing. See Research

Texas Experimental Tokamak (TEXT), 146

Theta pinch. See Reverse-field pinch

Three Mile Island (U.S.), 121 ‘

Tokamak Fusion Test Reactor (TFTR

breakeven experiments using, 70

construction of, 47, 49

cost Of, 95, 138

planning for, 9, 16, 47

shielding use in, 85

Tokamaks

40, 11, 47

breakeven experiment results using, 68-70

cooperation on experiments using, 159-160

fusion requirement demonstration by, 11-12, 57, 58,

59, 65

ignition experiments using, 70

major world, 59

progress in parameters of, 93, 94

Soviet development of, 9, 44-46, 59

See a/so Confinement; Magnets, Magnetic fields,

individual devices

Tore Supra tokamak (France), 86, 163

Toroidal chamber with magnetic coil. See Tokamak

Torus, magnetic fields encircling, 58, 59, 60-61, 58

Toshiba Corp., 149

Transfer

currency, 169, 171, 172

technology, 24, 25, 26, 158

Tritium (T), 40

breakeven attainment research, 46, 47, 70

breeding in fusion reactor blanket, 81, 82-83, 84, 85,

88, 91, 201-202

declassification of, generation technology, 43

in fusion reactions, 6, 30-31

hazards from accidental release of, 18, 106, 108

routine atmospheric releases of, 111

See a/so Hydrogen

Tritium Systems Test Assembly (TSTA), 88, 143, 90

Truman, Harry, 39

T-7 tokamak (Soviet Union), 86

T-1 5 tokamak (Soviet Union), 15, 48, 86, 180-181, 88

Umbrella agreements, 157-158, 159, 161-163

United Kingdom

fusion research in, 62, 63

JET facility located in, 160, 161

verification of Soviet tokamak results by, 45-46

See a/so European Community (EC)

United Kingdom Atomic Energy Agency, 161

United States

commitment to international cooperation, 168

ETR plans of, 98

fusion goals of, 29, 179
236 ● Starpower: The U.S. and the International Quest for Fusion Energy

fusion program status in, 16, 4 8 inertial confinement fusion research at, 207

fusion research in, 49, 59, 60, 61, 62-63, 64, 86 University of Texas, 146, 163

international cooperation by, 10, 26, 156, 159, University of Washington, 147

161-163, 171-173, 179, 184 University of Wisconsin, 64, 146, 147

stature of, and fusion research, 20, 44, 45, 133-134, Uranium

192, 196, 197 breeding in nuclear reactors, 112

Universities supply of. 19, 43, 122

DOE support of, 21, 132

fusion R&D conducted by, 21-22, 41, 132, 139,

143-147, 145

See a/so Private sector

University Fusion Associates (UFA), 21, 146

University of Arizona, 147

University of California

at Irvine, 147

at Los Angeles (UCLA), 146, 147

at Santa Barbara, 147

University of Illinois, 147

University of Maryland, 62, 147

University of Michigan, 147

University of Rochester

Utilities ‘ ‘ ‘

fusion energy’s acceptability to, 116, 117-119, 190,

118

fusion research “spin-off” technology and, 13 3

See a/so Private sector

Versailles economic summit, 183-184

Wastes, from fusion reactors, 18, 29-30, 83, 109-110,

110

Western Europe. See European Community (EC)

ZT-40, 144

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