2002 Fusion Summer Study
Snowmass Village, CO.
July 19, 2002
For Immediate Release

Fusion energy shows great promise to contribute to securing the energy future ofhumanity. The science that underlies this quest is at the frontier of the physics ofcomplex systems and provides the basis for understanding the behavior of hightemperature plasma.
Today 280 leading scientists from the U.S. and international fusion community
concluded a two-week forum assessing the major next steps in fusion energy science
research. The development of practical fusion power is one of the greatest scientificand technical challenges ever attempted. The 2002 Fusion Summer Study, held in theRocky Mountain’s Snowmass Village, offered opportunities for lively debate andcareful scientific analysis of proposed experiments that would accelerate scientificunderstanding of fusion plasmas and technologies. The conclusions reported today
provide critical input to the long range planning activities undertaken by the U.S.
Department of Energy and called for by energy legislation recently passed by theU.S. House of Representatives and the Senate. The results of the 2002 Fusion
Summer Study will be used by the DOE Fusion Energy Sciences Advisory
Committee to formulate a strategy to go forward with burning plasmas for the UnitedStates which will then be reviewed by the National Academy of Science.
Two approaches to fusion energy were discussed: magnetic fusion energy in whichhydrogen fuel is heated to more than 100 million degrees and held in place bypowerful magnets, and inertial fusion energy, in which small fuel capsules are heatedand compressed rapidly by intense energy pulses, and held together briefly by theirown inertia.
Preparation for the forum started over eight months ago when teams of experts began
to assemble the technical data needed to evaluate proposed “burning plasma”
experiments for magnetic fusion energy and plans for integrated researchexperiments in inertial fusion energy. The study of “burning plasma” is at thefrontier of magnetic fusion energy research and can occur only when the hydrogenfuel, or plasma, is strongly self-heated by fusion energy as in the sun and stars. An
integrated research experiment would demonstrate the science and technology
needed to deliver repetitive pulses of focused energy to a stream of fuel capsules.
World fusion scientists have designed several magnetic fusion burning plasma
experiments based on rapid scientific progress in the last decade. Fusion experimentsin the U.S. and Europe have produced over 10 million watts of fusion power andhave given scientists confidence to propose next step, burning plasma, experiments.

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One proposal, the International Thermonuclear Experimental Reactor (ITER), is theresult of many years of collaborative design and R&D effort (including the U.S.
through 1998) between Russia, Europe and Japan. Canada, Europe, and Japan haveoffered to host the device and negotiations are under way. This device is planned toincorporate large superconducting magnets, allowing near steady-state operation at
the scale of a future fusion power station. The U.S., as a founding member, has been
invited to join the ITER negotiations and is considering whether to do so. Resultsfrom the meeting at Snowmass will provide the basis for a policy decision by theUnited States to pursue a role in the ITER project.
A second burning plasma experimental option makes use of compact, high-fieldcopper magnets. An experiment with copper magnets would be smaller and lesscostly than ITER, but it would also result in shorter pulses during which burning
plasmas could be studied. Two experimental proposals, FIRE (developed in the U.S.)
and IGNITOR (developed in Italy), are of this type.
The National Ignition Facility (NIF), a machine designed to demonstrate ignition andburn of inertial fusion plasma is currently under construction as part of the US
Department of Energy Defense Programs. NIF will be able to test a wide variety oftarget concepts for inertial fusion but it is not designed to have the pulse repetition
rate, shot lifetime, or efficiency needed for commercial power production. Research
separate from NIF is developing devices with these capabilities.
Gas and solid-state lasers, as well as intense ion beams, are under consideration for
an integrated research experiment. Most recently ideas using an intense pulsed
electrical current have been proposed. A new technology, using very fast lasers toignite the fusion fuel (called “fast ignition”) has also caught the interest ofresearchers.
The 2002 Fusion Summer Study resulted in six major conclusions for both magnetic
and inertial fusion energy.
For magnetic fusion energy, the forum concluded:
1. The study of burning plasmas, in which self-heating from fusion reactions
dominates plasma behavior, is at the frontier of magnetic fusion energy
science. The next major step in magnetic fusion research should be a burning
plasma program, which is essential to the science focus and energy goal offusion research.
2. The three experiments proposed to achieve burning plasma operation range
from compact, high field, copper magnet devices to a power-plant-scale
superconducting-magnet device. These approaches address a spectrum of

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both physics and fusion technology, and vary widely in overall mission,schedule and cost.
3. IGNITOR, FIRE, and ITER would enable studies of the physics of burning
plasma, advance fusion technology, and contribute to the development offusion energy. The contributions of the three approaches would differ
considerably.
(i) IGNITOR offers an opportunity for the early study of non-stationary
burning plasmas aiming at ignition.
(ii) FIRE offers an opportunity for the study of burning plasma physics inconventional and advanced tokamak configurations under quasistationary conditions and would contribute to plasma technology.
(iii)ITER offers an opportunity for the study of burning plasma physics inconventional and advanced tokamak configurations for long durations
with steady state as the ultimate goal, and would contribute to thedevelopment and integration of plasma and fusion technology.
4 . There are no outstanding engineering-feasibility issues to prevent thesuccessful design and fabrication of any of the three options. However, thethree approaches are at different levels of design and R&D. There isconfidence that ITER and FIRE will achieve burning plasma performance in
H–mode based on an extensive experimental database. IGNITOR would
achieve similar performance if it either obtains H–mode confinement or anenhancement over the standard tokamak L–mode. However, the likelihood ofachieving these enhancements remains an unresolved issue between theassessors and the IGNITOR team.
5. The development path to realize fusion power as a practical energy source
includes four major scientific elements:(i) Fundamental understanding of the underlying science and technology,
and optimization of magnetic configurations(ii) Plasma physics research in a burning plasma experiment(iii) High performance, steady-state operation(iv) Development of low-activation materials and fusion technologies
6. A strong base science and technology program is needed to advance essential
fusion science and technology and to participate effectively in, and to benefit
from, the burning plasma effort. In particular, the development path forinnovative confinement configurations would benefit from research on a
tokamak-based burning plasma experiment.
For inertial fusion energy, major conclusions from the forum are:
1. The National Ignition Facility (NIF) is expected to produce a burning inertial
fusion plasma. The National Nuclear Security Administration is currently
building the National Ignition Facility.
2. Laser systems for Inertial Fusion Energy have made impressive progress inefficiency, pulse rate, and lifetime. KrF lasers require further improvement in2002 Summer Fusion Study

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lifetime, and solid-state lasers require improvement in the cost of major
components.
3. The heavy ion fusion program has made excellent progress in basic beamscience. Several new science experiments have recently begun operations.
Integrated experiments at moderate beam energy and current, including
focusing intense beams in the chamber environment remain the important
technical issues.
4. There has been impressive progress in z-pinch targets and good progress inconceptual power plant designs. Producing economical recyclable
transmission lines at low cost remains the most important issue.
5. Chamber technology and target fabrication and injection are being placed ona sound scientific basis. For example, experiments on dry-wall damage limits
are underway. Scaled hydraulics experiments have identified nozzle designs
that can create all liquid jet configurations required for thick liquid chambers,
and a target injection experiment is under construction. For heavy-ion fusion
there is now a chamber design where the final focus magnets and chamber
structures have predicted lifetimes exceeding 30 years.
6 . There is broad international interest in fast ignition. If fast ignition is
successful, it will produce higher energy gains than conventional targets. So
far the target experiments have been encouraging, particularly the recentJapanese results. Fast ignition power production is at a rudimentary level for
all drivers. An integrated research plan is required.
Fusion offers a clean and safe new energy source. With no carbon dioxide emissions,fusion energy provides a long-term solution to the problem of global warming. The
next major steps for how to bring this new energy source to humanity are now on thetable for consideration by policy-makers.
For further information on this subject contact:
Dr. Roger O. Bangerter (Co-Chair of 2002 Fusion Summer Study)
Lawrence Berkeley National Laboratory
Phone (925) 831-1453Email ROBangerter@lbl.gov
Prof. Gerald A Navratil (Co-Chair of 2002 Fusion Summer Study)
Columbia University
New York NY 10027
Phone (212) 854-4496
Email navratil@columbia.edu
Dr. Ned Robert Sauthoff (Co-Chair of 2002 Fusion Summer Study)
Princeton Plasma Physics Laboratory
Princeton University
Princeton NJ 08543-0451
Phone (609) 243-3207
Email sauthoff@pppl.gov

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