United States Air and Energy Engineering

Environmental Protection Research Laboratory

Agency Research Triangle Park, NC 27711

Research and Development EPA/600/SR-94/008 March 1994

E AP Project Summary

The report documents results of the

1992 Greenhouse Gas Emissions and

Mitigation Research Symposium, sponsored by the U.S. Environmental Protection Agency's Air and Energy Engineering Research Laboratory (EPAAEERL), and held in Washington, D.C.,

on August 18-20, 1992. The symposium

provided a forum of exchange of technical information on global change

emissions and potential mitigation technologies. The primary objectives of the

meeting were dissemination of technical information and education in recent

research. Oral papers along with an

international panel discussion,

overheads, slides, and a GloED demonstration proved for lively exchanges

in the following areas: activities in EPA,

U.S. Department of Energy (DOE), and

Electric Power Research Institute (EPRI)

on greenhouse gas emissions and mitigation research, and AEERL's global

emissions and technology databases;

international activities of selected industrialized and developing countries;

carbon dioxide (CO2

) emissions and

their control, disposal, and reduction

through conservation and energy efficiency, and carbon sequestration including utilization of waste CO2

; methane (CH4) emissions and mitigation

technologies including such topics as

coal mines, the natural gas industry,

key agricultural sources, landfills and

other cookstove emissions and control

approaches; and solar and renewable

energy sources, including renewable

energy options, alternative biomass fuProceedings: The 1992

Greenhouse Gas Emissions and

Mitigation Research Symposium

els, advanced energy systems, solar

energy developments, and woodstove

emissions and mitigation. The proceedings contain 34 submitted papers.

This Project Summary was developed

by EPA's Air and Energy Engineering

Research Laboratory, Research Triangle Park, NC, to announce key findings of the research project that is fully

documented in a separate report of the

same title (see Project Report ordering

information at back).

Introduction

The 1992 Greenhouse Gas Emissions

and Mitigation Research Symposium,

sponsored by the U.S. Environmental Protection Agency’s Air and Energy Engineering Research Laboratory (EPA/AEERL)

and Acurex Environmental Corporation

was held August 18-20, 1992, in Washington, DC. Thirty-four speakers presented

papers on recent research on global

change emissions and potential mitigation

technologies. The symposium Chairperson was Robert P. Hangebrauck of EPA/

AEERL. This project summary includes

abstracts of the papers presented at the

symposium. The six sessions were:

I. Overview

II. International Activities

III. CO2

, Emissions, Control, Disposal,

and Utilization

IV. Emissions and Mitigation of Meth

ane and Ozone Precursors

V. Biomass Emission Sources and

Sinks

VI. Energy Sources/Solar/Renewable

Sue Philpott, Compiler
2

Session I

Overview

(Frank T. Princiotta, EPA, Session

Chairperson)

"Greenhouse Warming: The Mitigation

Challenge," Frank T. Princiotta, EPA)

This paper describes the symposium as

a forum to discuss the state-of-the-art and

research opportunities associated with the

sources and mitigating releases of greenhouse gases. Essential to discussing mitigation opportunities is the understanding

of fundamental driving forces for releases

of these gases, relating projected emissions to anticipated global warming, examining the important greenhouse gases

and their relative contributions, and understanding the penalties associated with

delaying implementation of a mitigation

program.

"Methane Reductions are a CostEffective Approach for Reducing

Emissions of Greenhouse Gases,"

Kathleen B. Hogan and Dina W.

Kruger, EPA

Methane reductions can play a large

role in providing low cost, if not profitable,

opportunities for reducing greenhouse gas

emissions, in addition to other benefits for

the atmosphere. This paper reports on

opportunities for reducing emissions of

methane that have been examined through

a number of EPA efforts and activities

developed by the Intergovernmental Panel

on Climate Change. The paper concludes

that efforts to encourage methane reductions will require identification and removal

of a number of barriers that hinder the

implementation of available technologies.

"Climate Change and Related

Activities," Kenneth Freidman, DOE

This report is a brief discussion of the

U.S. Department of Energy’s (DOE’s) activities in scientific research, technology

development, policy studies, and international cooperation that are directly related

to or have some bearing on the issue of

global climate change. Part I describes

DOE’s major activities: 1) developing computer models to predict rate and magnitude of global and regional climate change,

2) understanding the systems that control

the current and past climates of the Earth,

and 3) exchanging and communicating

data and modeling results with other climate researchers around the world. Part

II focuses on DOE’s related activities including scientific research; transportation;

alternative fuels development; residential,

commercial, and industrial efficiency; appliance and equipment efficiency; industrial process technologies; industrial waste

minimization; electricity generation and

use; and policy analysis.

"EPRI’s Greenhouse Gas Emissions

Assessment and Management

Research Program," D.F. Spencer and

G.M. Hidy, EPRI

This paper briefly reviews the rationale

and need for an electric utility greenhouse

gas emissions assessment and management research program, as well as potential cost implications to society of shortterm control requirements. The balance of

the paper focuses on EPRI’s directly related R&D program and its key elements,

namely: a) model development and model

evaluation activities, b) ecological effects,

c) management/mitigation research, and

d) development of an integrated assessment framework. EPRI’s directly related

greenhouse gas research program, including co-funding, is expected to expend approximately $60 million over the next 4

years to address key aspects of this significant environmental issue.

"Global Emissions Database (GloED)

Software," Lee Beck, EPA

The EPA Office of Research and Development has developed a powerful software package called the Global Emissions

Database (GloED). GloED is a user-friendly,

menu-driven tool for storage and retrieval

of emissions factors and activity data on a

country-specific basis. Data can be selected from databases resident within

GloED and/or imputed by the user. The

data are used to construct emissions scenarios for the countries and sources selected. References are linked to the data

to ensure clear data pedigree. The scenario outputs can be displayed on thematic global maps or other graphic outputs such as bar or pie charts. In addition,

data files can be exported as Lotus 1-2-3,

dBase, or ASCII files, and graphics can

be saved as a PCX file or exported to a

printer. This paper describes GloED and

how it works. It also presents future plans

for software enhancements and populating the databases.

Session II

International Activities

(Jane Leggett, EPA, Session

Chairperson)

"Beyond Rio," Hans van Zijst, Royal

Netherlands Embassy

This brief narrative explores the Dutch

perspective on the future of research and

policies on climate change. Current policy

goals and measures taken by the Dutch

government are examined, which include

issues such as energy savings, fuel consumption, traffic and transport, and the

waste sector. The paper emphasizes the

strong need for international cooperation

in implementing the Convention on Climate Change.

Session III

CO2

, Emissions, Control,

Disposal, and Utilization

(Ken Freidman, DOE, Session

Chairperson)

"Carbon Dioxide Sequestration,"

Robert P. Hangebrauck, Robert H.

Borgwardt, and Christopher D. Geron,

EPA

Mitigation of global climate change will

require the stabilization of atmospheric

concentration of greenhouse gases, especially carbon dioxide (CO2

). CO2 can be

sequestered by flue-gas and fuel CO2 sequestration or by atmospheric CO2 fixation/utilization. Flue-gas sequestration involves separation/concentration, transport,

and either disposal or use. Disposal options are either land or ocean based. Utilization is by either chemical or biological

utilization (recycling). Flue-gas-oriented

techniques in general have high economic

and energy costs, but a few areas show

potential and warrant research and development (R&D) attention, especially those

holding promise of combined CO/sulfur

dioxide (SO2

)/nitrogen oxides (NOx) control and the integrated gasification combined cycle approaches. CO2 disposal is

neither a “sure thing” nor a permanent

solution, with options needing further environmental assessment. Near term, some

CO2 recycling is possible, and R&D to

examine longer-term prospects seems

warranted. Atmospheric CO2

 fixation/utilization involves either enhanced terrestrial or

marine fixation with utilization of the biom-
3

ass in some cases. Atmospheric fixation

approaches which seem most attractive

are those involving enhanced biomass CO2

sequestration combined with utilization of

the biomass for energy to displace fossil

fuel. Of these, the most attractive for R&D

appear to be advanced direct combustion

using biomass and use of biomass as a

source of hydrogen to leverage fossil fuel

use for methanol production (Hydrocarb

process).

"The NOAA Carbon Sequestration

Program," Peter Schauffler, National

Oceanic and Atmospheric

Administration

Increasing attention is being given to

oceanic techniques for sequestering carbon in various molecular forms as part of

an overall global-change strategy. EPRI,

through a Caltech contract, is looking at

the formation and semi-permanent retention of CO2

 hydrates at ocean depths of

1,000 m or so. Similar investigations are

being actively pursued by the Japanese.

EPRI and NOAA, assisted by Caltech and

George Washington University, are re-examining the feasibility of large-scale farming of microalgae as a way of collecting

CO2

 from the atmosphere and upper ocean

layers, sequestering it in liquid or hydrate

form in the deep ocean and/or locking up

the carbon in the farm structure, and using the farm-produced methane and perhaps methanol as a CO2

-neutral fossil fuel

substitute.

"The Role of DOE Energy Efficiency

and Renewable Energy Programs in

Reducing Greenhouse Gas

Emissions," Eric Peterson, DOE

This presentation illustrates DOE’s programs in energy conservation and energy

efficiency, and renewable, nuclear and fossil energy technology research and development. The history and the mission of

the Office of Conservation and Renewable Energy is described. Also, overviews

of other DOE-initiated programs such as

the Wind Energy Program are given.

"Fuzzy Logic Control of AC Induction

Motors to Reduce Energy

Consumption," R.J. Spiegel and P.

Chappell, EPA; J.G. Cleland, Research

Triangle Institute; and B.K. Bose,

University of Tennessee

Fuzzy logic control of electric motors is

being investigated under sponsorship of

EPA to reduce energy consumption when

motors are operated at less than rated

speeds and loads. Electric motors use

60% of the electrical energy generated

in the U.S. An improvement of 1% in

operating efficiency of all electric motors

could result in savings of 17 x 109 kWh/yr

in the U.S.. New techniques are required

to extract maximum performance from

modern motors. This paper describes

EPA’s research program, as well as early

stages of work, to implement fuzzy logic

to optimize the efficiency of alternating

current (AC) induction motors.

"Evaluation of Methanol Production

from Hydrogen and Waste Carbon

Dioxide," Stefan Unnasch and Dan

Luscher, Acurex Environmental

Corporation

The production of methanol from waste

carbon dioxide (CO2

) and hydrogen was

evaluated. Using recycled CO2

 in methanol fuel would reduce the emissions of

CO2

 into the atmosphere. We investigated

the cost and technical status of potential

non-fossil hydrogen production technologies and CO2

 recovery technologies. The

primary focus for hydrogen production was

an photovoltaic (PV) power sources.

Methanol can be produced from CO2 and

hydrogen by reacting CO2

 with hydrogen

to form carbon monoxide (CO) and water.

The CO is then reacted with hydrogen to

form methanol. Producing 1.0 lb of methanol with this approach would require 4.37

kWh of electrical power for the production

of hydrogen and capture of CO2. The

methanol would cost over $3.00/gal if the

power were derived from current PV technology; about 85% of this cost is associated with hydrogen production. This cost

could be reduced by 70% with improvements in PV technology that are expected

to be feasible with large scale production

and projected advances in technology. Almost all of the carbon in a coal gasification system can be converted to methanol

with the addition of hydrogen. Producing

1.0 lb of methanol from coal would require

only 1.89 kWh of electric power.

Session IV

Emissions and Mitigation of

Methane and Ozone Precursors

(M.J. Shearer, Global Change

Research Center, Session

Chairperson)

"Global Atmospheric Methane: Trends

of Sources, Sinks and

Concentrations," M.A.K. Khalil, R.A.

Rasmussen, and M.J. Shearer, Global

Change Research Center

The global cycle of methane is driven

by emissions around 550 Tg/yr from both

natural and sources related to anthropogenic activities, particularly the production

of food and energy. Major sources are

rice agriculture, domestic ruminants, and

wetlands. Methane is removed from the

atmosphere mostly by reacting with OH

radicals. Some methane is removed by

the soils. Over the past decade methane

concentrations have been increasing at

about 1%/yr or 16 ppbv/yr. A record of

atmospheric methane extending back

150,000 years has been constructed from

the analysis of polar ice cores. It shows

that, during this time, methane concentrations have never been more than half of

present levels. The recent increase of

methane was probably caused by increasing emissions. Recent changes in the trend

of methane may also be attributed to

changing levels of OH. This paper deals

with the changes in global methane concentrations in the past, the causes of increased levels at present, and the future

of atmospheric methane. The present understanding of the global methane budget provides critical facts for policies related to controlling anthropogenic sources.

"Coal Mine Methane Emissions and

Mitigation," David A. Kirchgessner,

EPA; and Stephen D. Piccot, Science

Applications International Corporation

Estimates of methane (CH4) emissions

from coal mines range from 25 to 45 Tg/yr

with a recent estimate as high as 65 Tg/

yr. At 46 Tg/yr, the estimate produced by

this project, coal mines contribute about

10% of anthropogenic CH4

 emissions and

may contribute significantly to the global

change phenomenon. Although emissions

from underground mines are now believed

to be adequately characterized, virtually

no data are available on emissions from

surface mines, and data are totally lacking on emissions from abandoned/inactive mines and coal handling operations.

The methodology developed to calculate

emissions from underground mines is

briefly described, as is the Fourier transform infrared spectroscopy technique being employed for measuring emissions

from surface mines. A nitrogen-flooding

technique for enhancing the recovery of

CH4

 from coalbeds in advance of mining

is described as a possible measure for

mitigating CH4 emissions from underground mines.

"Emissions and Mitigation of Methane

from the Natural Gas Industry," Robert

A. Lott, Gas Research Institute

The Gas Research Institute and EPA

are co-funding and co-managing a pro-
4

gram to evaluate methane emissions from

U.S. natural gas operations. The purpose

of the program is to provide an emissions

inventory accurate enough for global climate modeling and for addressing the

policy question of “whether encouraging

the increased use of natural gas is a viable strategy for reducing the U.S. contribution to global warming.” The program is

comprised of three phases: Scoping, Methods Development, and Implementation.

The purpose of Phase I was to define

the problem. Phase II of the program concentrated on developing techniques for

measuring steady state or fugitive emissions and for calculating the highly variable unsteady emissions from the variety

of sources that comprise the gas industry.

Because of the large number of sources

within each source type, techniques were

also developed for extrapolating emissions

data to similar sources within the industry.

Phase III of the program was started in

early 1992 and should be completed in

early 1994. The purpose of the current

phase of the program is to collect sufficient data to achieve the accuracy goal of

determining emissions to within + 0.5% of

production.

Based on the limited amount of data

collected to date, methane emissions from

the U.S. gas industry appear to be in the

range of 1% of production.

"Emissions and Mitigation at Landfills

and Other Waste Management

Facilities," Susan A. Thorneloe, EPA

Landfills and other waste management

sources of methane are amenable to

cost-effective control. Consequently, these

sources have been given a high priority

for clarification of their emission potential.

EPA is conducting research to determine

the emission potential and mitigation opportunities for cost-effective control for the

major sources of greenhouse gases. EPA/

AEERL is responsible for developing more

reliable global and country-specific estimates for the major sources of greenhouse gases including waste management,

coal mines, natural gas production/distribution, energy usage, cookstoves, and biomass combustion. AEERL has gathered

data that have resulted in the development of more reliable estimates for landfills. Research has been initiated to characterize the methane potential of other

waste management facilities including

wastewater treatment lagoons, septic sewage systems, and livestock waste.

AEERL is also documenting the current

state of technology for utilization projects.

Currently, 114 landfill gas-to-energy

projects are occurring in the U.S. and

about 200 worldwide. Technology transfer/technical assistance programs have

been initiated to help encourage the utilization of waste methane and to help implement the upcoming Clean Air Act (CAA)

regulations for municipal solid waste landfills. For example, AEERL is working with

a consortium of local government representatives to explore the application of

EPA research on methane/energy recovery from municipal solid waste landfills.

AEERL also serves on the International

Energy Agency Expert Working Group on

Landfill Gas and the Steering Committee

for the Solid Waste Association of North

America. AEERL is also responsible for

demonstrating innovative approaches to

the control of waste methane such as the

application of fuel cell technology to recover energy from landfills gas and digester gas.

This paper describes the emission potential for waste management sources and

the mitigation opportunities. It also provides an overview of some of the barriers

in the U.S. that affect methane utilization.

This research is funded through EPA’s

Global Climate Change Research Program.

"Fuel Cell Power Plant Fueled by

Landfill Gas," R.J. Spiegel, EPA, and

G.J. Sandelli, IFC

International Fuel Cells Corporation

(IFC), a subsidiary of United Technologies Corporation, is conducting an EPAsponsored program to demonstrate methane control from landfill gas using a commercial phosphoric acid fuel cell power

plant. This is the world’s first commercialscale demonstration to control methane

emissions from landfills using a fuel cell

energy recovery system. EPA is interested

in fuel cells for this application because it

is potentially the cleanest energy conversion technology available. This paper discusses the project in general and describes

some results to date, with emphasis on

the landfill gas pretreatment system.

"Methane Emissions from Rice

Agriculture," M.A.K. Khalil, M.J.

Shearer, and R.A. Rasmussen, Global

Change Research Center

Rice agriculture has long been recognized as a major source of methane (CH4).

Global budgets of methane have generally included emissions of about 100 Tg/yr

(Tg = 1012 g) from rice agriculture (range

of 50-300 Tg/yr) and constituting about

20% of emissions from all sources (range

14-40%).

During the last decade, a number of

systematic experiments have been reported on methane emissions from rice

fields. Seasonal averages range from 0 to

40 mg/m2/hr. Factors affecting the flux of

methane include irrigation regime, fertilizer, soil temperature, and soil type.

The most recent global estimates put

the emissions from rice paddies at 50 to

100 Tg/yr. The major cause of increasing

methane emissions from rice paddies over

the past 50 years appears to be the tremendous increase in area planted to rice.

Emissions appear to have stabilized over

the past decade. Future increases in methane emissions from rice will probably depend on access to irrigation and the use

of organic fertilizer.

"Livestock Methane: Sources and

Management Impacts," Donald E.

Johnson, T. Mark Hill, and G.M. Ward,

Colorado State University

Herbivorous animals, particularly ruminants, have a digestive tract that facilitates extensive symbiotic microbial digestion of dietary structural plant carbohydrates. A by-product of this symbiotic microbial process is an estimated 70 Tg of

methane globally per year, primarily from

cattle and buffalo. Cattle methane emissions equal 6 +/- 0.5% of their diet energy

(2% by wt) for most global conditions studied. Emissions by U.S. feedlot cattle are

uniquely lower at about 3.5% of diet energy. A major lack of information on size,

diet, class distribution and percentage loss

from developing country livestock precludes accurate definition of this source,

which is about 65% of global. Manure

disposal from livestock may produce an

additional 12 Tg globally, primarily through

anaerobic lagoons. Possible ameliorative

strategies include the decreased use of

lagoon disposal or the capture of this methane. General efforts should concentrate

on improving productivity of beef and dairy

cattle production systems, which will secondarily reduce methane.

"Ozone and Global Warming," Robert

P. Hangebrauck and John W. Spence,

EPA

Changes in several trace substances in

the Earth’s atmosphere are affecting global radiative forcing. Those substances

that seem to be in the greatest state of

change now and projected into the future

are carbon dioxide, ozone (and its precursors and depleters), and aerosols. Conceivably, countervailing changes in the radiative forcing effects of these substances,
5

especially ozone and aerosols, may be

temporarily hiding or at least changing the

“greenhouse signal”—an unfortunate circumstance, particularly if the overall impacts that will eventually occur are unpredictable or difficult to reverse quickly. If in

fact the greenhouse signal is partially being obscured at present, there is also potential for this effect becoming less significant in the decades ahead because of 1)

a continuation of increases in greenhouse

gas emissions, 2) saturation of the tropospheric aerosol effect plus controls on sulfur emissions, and 3) increasing tropospheric ozone. The substantial complexities in factors affecting ozone and aerosols are discussed with emphasis on ozone

and its precursors, including methane, nonmethane hydrocarbons, carbon monoxide,

and nitrogen oxides. Quantifying radiative

forcing is of substantial importance. EPA

is undertaking research to enhance the

ability to estimate indirect factors contributing to forcing, including measures such

as Global Warming Potentials. Many of

the important but difficult factors to resolve are of the indirect type. A number of

potential indirect forcing effects are identified along with an estimate of direction

(sign).

"Overview of Methane Energy and

Environmental Research Programs in

the United Kingdom," Suzanne A.

Evans, Anton van Santen, Paul S.

Maryan, Caroline A. Foster, Keith M.

Richards, Harwell Laboratory

The biofuels program of research and

development forms an important part of

the UK Department of Energy’s renewable energy program. This program began in the mid-1970s as a response to

the oil crisis of that time and was part of a

much wider look at alternative energy supplies. The initial driving force for biofuels

and other renewables research was the

prospect of greater diversity, and hence

security of energy supply for the nation.

More recently, concerns over the environment and the need for sustainable sources

of energy have added further strength to

the case for using “environmentally

friendly” renewables. This paper reviews

the history of the biofuels program, its

present content, and considers where future emphasis might lie.

Session V

Biomass Emission Sources and

Sinks

(Robert Dixon, EPA, Session

Chairperson)

"The Carbon Balance of Forest

Systems: Assessing the Effects of

Management Practices on Carbon

Pools and Flux," Robert K. Dixon and

Jack K. Winjum, EPA, and Paul E.

Schroeder, ManTech Environmental

Technology, Inc.

Forests play a major role in the Earth’s

carbon cycle through assimilation, storage, and emission of CO2. Establishment

and management of boreal, temperate,

and tropical forest and agroforest systems

could potentially enhance sequestration of

carbon in the terrestrial biosphere. A biologic and economic analysis of forest establishment and management options from

94 nations revealed that forestation,

agroforestry, and silviculture could be employed to conserve and sequester 1

gigaton (Gt) of carbon annually over a 50-

year period. The marginal cost of implementing these options to sequester 55 Gt

of carbon would be approximately $10/

ton.

"Global BIOME (BIOspheric Mitigation

and adaptation Evaluation) Program,"

Robert K. Dixon and Jack K. Winjum,

EPA

Preliminary assessments suggest that

forests and agroecosystems can be managed to conserve and sequester carbon,

thereby reducing the accumulation of

greenhouse gases in the atmosphere. Biomass utilization is a necessary component of a sustained terrestrial carbon sequestration effort. The Global BIOME

(BlOspheric Mitigation and adaptation

Evaluation) Program will consist of a) technical assessments of effectiveness of terrestrial biosphere management options and

biomass fuel technology in reducing atmospheric accumulation of greenhouse

gases, b) demonstration projects to assess the technical and economic feasibility of applying agricultural and forest management options and biomass fuel substitution, c) regional, national, and global

assessments of effectiveness of terrestrial

biosphere management and adaptation

options, and d) assessment of practices

and technologies that, if implemented,

could facilitate adjustment of forest and

agroecosystems to global climate change.

The Global BIOME initiative is a component of EPA’s Office of Research and

Development national Global Change Research Program. The research is managed by the Agency’s laboratories: ERL-A,

ERL-C, AEERL, and AREAL. Research is

conducted by EPA scientists in cooperation with universities, other federal agencies and laboratories, and contractors.

"Agricultural Management and Soil

Carbon Sequestration: An Overview of

Modeling Research," Robert B.

Jackson IV and Thomas O. Barnwell

Jr., EPA; Anthony S. Donigian Jr. and

Avinash S. Patwardhan, Aqua Terra

Consultants; and Kevin B. Weinrich

and Allen L. Rowell, Computer

Sciences Corporation

Soil carbon fluxes and pools are profoundly affected by agricultural management, which is in turn affected by national

and international agricultural policies. This

paper briefly describes the framework and

some details of a computer modeling research strategy that is being implemented

at the Athens Environmental Research

Laboratory (AERL). The objective of the

research is to determine the potential for

U.S. agroecosystems to accumulate and

sequester carbon as a means of slowing

the global increase in atmospheric carbon

dioxide.

"Assessment of the Biogenic Carbon

Budget of the Former Soviet Union,"

Tatyana P. Kolchugina and Ted S.

Vinson, Oregon State University

A framework was created to quantify

the natural terrestrial carbon cycle of the

former Soviet Union (FSU). The organization of the carbon cycle parameter and

georeferenced database, which supports

the framework and the calculations, which

are required to establish the carbon budget, are performed with personal computer hardware and commercially available spreadsheet software. Based on the

framework, net primary productivity (NPP)
6

for the FSU was estimated at 6.2 +/- 1.7

GT (109 tons) C/yr, the vegetation carbon

pool at 118.1 +/- 28.5 GT C, the litter

carbon pool at 18.9 + 4.4 GT C, and total

soil carbon pool at 404.0 +/38.0 2GT C.

The components of the carbon budget

obtained with the framework were in good

agreement with estimates from other published sources. The framework will allow

the role of the FSU in the global carbon

cycle to be assessed. The extent of forest

and agricultural ecosystems within the FSU

that can be technically managed on a

sustainable basis to conserve and sequester carbon may also be determined with

the framework.

"Household Fuels in Developing

Countries: Global Warming, Health,

and Energy Implications," Kirk R.

Smith, Program on Environment, and

Susan A. Thorneloe, EPA

Although individually small, the widespread and daily use of household stoves

with poor combustion efficiency in developing countries raises questions about

possible global warming and other environmental implications of their airborne

emissions. To explore the possible utility

of efforts to measure the emissions from

representative samples of these devices,

a small pilot study of greenhouse gas

emissions of biomass and fossil-fuel stoves

was undertaken in Manila. The results,

although based on only a few measurements, indicate that such stoves may have

a significant role in global greenhouse gas

inventories; be subject to substantial improvement through alternative technologies; and that policy measures should consider energy and health implications as

well. As a consequence, a larger set of

studies is being planned for India, China,

Thailand, and Brazil. This research is

funded through EPA’s Global Climate

Change Research Program. Research on

emissions and mitigation of major sources

of greenhouse gases is being conducted

by EPA/AEERL.

"The Potential for Energy Crops to

Reduce Carbon Dioxide Emissions,"

R.L. Graham, Oak Ridge National

Laboratory

Energy crops are herbaceous or woody

plants grown specifically to produce biomass for combustion and production of electricity or for conversion to fuels such as

ethanol. When grown intensively, such

crops can yield up to 43 dry Mg biomass/

ha/yr in the temperate zone although yields

of 10 to 20 Mg are more typical.

By substituting sustainably grown biomass for fossil fuels, CO2

 emissions from

energy consumption can be reduced significantly. Although biomass fuels are net

emitters of CO2

, because fossil fuels are

used in the production of energy crops

(e.g., fertilizers, transportation), biomass

fuels emit much less CO2

 than fossil fuels

per unit of energy produced. A hectare of

U.S. farmland on the average could produce sufficient biomass to reduce annual

CO2 emissions by 5 Mg C if such biomass

were used to produce electricity that would

otherwise be produced with coal.

Within the U.S., at least 131 million

hectares of farmland could support energy crop production. Much of this land

lies in the midwest although the southeast

also contains considerable acreage. More

acreage can support herbaceous energy

crops than woody crops as there are herbaceous crops that can tolerate drier conditions than any woody crop.

The potential for energy crops to reduce CO2

 emissions will depend on how

much land can be profitably dedicated to

energy crops. Farmers will adopt energy

crops when it is economically advantageous for them to do so. Power companies will adopt biomass energy when the

cost of energy from fossil fuels exceeds

that from biomass. Government policies

and regulations affect both these relationships. Currently biomass crops must compete with subsidized agricultural crops

thereby inflating the price of biomass to

an energy facility. On the other hand, pollution regulations can favor energy crops

as a fuel source since biomass crops can

burn cleaner than coal.

Session VI

Energy Sources/Solar/

Renewable

(Robert Williams, Princeton

University, Session Chairperson)

"Roles for Biomass Energy in

Sustainable Development," Robert H.

Williams, Princeton University

Biomass (plant matter) accounts for

15% of world energy use and 38% of

energy use in developing countries. But

most biomass is used inefficiently, mainly

for cooking and heating in rural areas of

developing countries, and often in much

the same way it has been used for millennia. Biomass can also be converted into

modern energy carriers such as gaseous

and liquid fuels and electricity that can be

widely used in more affluent societies. The

most promising options are biomass-integrated

gasifier/gas turbine power systems as an alternative to coal-based power plants and

biofuels for fuel-cell vehicles as an alternative

to gasoline for internal-combustion-engine vehicles. The prospects are good that these

technologies could be competitive with conventional fossil fuel technologies at present

world energy prices.

The large-scale utilization of biomass

for energy can provide a basis for rural

development and employment in developing countries, thus helping to curb urban

migration. In addition, if biomass is grown

sustainably, its production and use creates no net buildup of carbon dioxide (CO2)

in the atmosphere, because the CO2 released during combustion is offset by the

CO2 extracted from the atmosphere during photosynthesis.

Biomass for energy can be obtained

from residues of ongoing agricultural and

forest product industries, from harvesting

forests, and from dedicated plantations.

The harvesting of forests for biomass is

likely to be limited by environmental concerns. Over the next couple of decades

new bioenergy industries will be launched

primarily using residues as feedstocks.

Subsequently, the industrial base will shift

to plantations, the largest potential source

of biomass.

The most promising sites for plantations are deforested and otherwise degraded lands in developing countries and

excess croplands in the industrialized

countries. Revenues from the sale of biomass crops grown on plantations established on degraded lands can help finance

the restoration of these lands. Establishing plantations on excess croplands can

be a new livelihood to farmers who would

otherwise abandon their land because of

foodcrop overproduction. In either case,

biomass plantations can, with careful planning, substantially improve these lands

ecologically relative to their present uses.

But a substantial and sustained research

and development effort is needed to ensure the realization and sustainability of

high yields under a wide range of growing

conditions. Moreover, the establishment

and maintenance of biomass plantations

must be carried out in the framework of

sustainable economic development in

ways that are acceptable to the local

people.

Ultimately, land and water resource constraints will limit the contributions that biomass can make as an energy source in
7

advanced societies. But biomass energy

can make major contributions to sustainable development before these limits are

reached, if biomass is grown productively

and sustainably and efficiently converted

to modern energy carriers that are used in

energy efficient end-use technologies.

"An Analysis of the Hydrocarb Process

for Methanol Production from

Biomass," Yuanji Dong and Meyer

Steinberg, Hydrocarb Corporation, and

Robert H. Borgwardt, EPA

A pilot plant is being designed to evaluate the technical feasibility of producing

transportation fuel from biomass by the

Hydrocarb process. As a basis for that

design, computer simulations and experimental studies have been carried out to

establish optimum process conditions for

a range of feedstocks that are anticipated

for pilot plant tests. This paper discusses

the results of simulations to determine the

operating parameters and performance

when using urban wastes such as

greenwaste and sewage sludge as feedstocks. The simulations were used to configure the process steps for maximum fuel

(methanol) production, to determine feed

rates, and to estimate thermal efficiency.

The results indicate that about 77 kg of

methanol can be produced from 79 kg of

dry greenwaste when sludge and digester

gas are fed as co-feedstocks in a ratio of

0.2. The optimum system pressure is found

to be 50 atm (5 MPa). Temperatures of

900°C for gasification and 1000°C for

methane pyrolysis are recommended on

the bases of thermodynamics, kinetics,

and the limitations of materials of construction. Thermal efficiency at these conditions is estimated to be 74%.

"Alternative Fuels from Biomass,"

Charles E. Wyman, National

Renewable Energy Lab

Substitution of biofuels derived from cellulosic biomass for conventional fuels

would reduce the accumulation of carbon

dioxide in the atmosphere and the possibility of global climate change, improve

our energy security and trade deficit, revitalize rural and farm economies, and address urban air pollution and waste disposal problems. The major fractions of

biomass, cellulose and hemicellulose, can

be broken down into sugars that can be

fermented into ethanol. Through technology advances for producing ethanol, the

projected cost at the plant gate has been

reduced from about $3.60/gal 10 years

ago to $1.27/gal, and opportunities have

been identified to further drop the price to

$0.67/gal, a price competitive with gasoline from oil at $25/bbl, within 10 years.

Through anaerobic digestion, a consortium of bacteria can break down cellulosic

biomass to generate a medium-Btu gas

that can be cleaned up for pipeline-quality

methane. The cost of this methane has

been reduced to about $4.50/MBtu (106

Btu) for municipal solid waste (MSW) feedstocks, and technology advances could

drop the price to about $2.00/MBtu. Algae

could consume carbon dioxide from power

plants and produce lipid oil that can be

converted into a diesel fuel substitute. Projected costs for this biodiesel have dropped

from almost $18.00/gal to about $3.50/gal

now, with a target of $1.00/gal. Biomass

can also be gasified to a mixture of carbon monoxide and hydrogen for catalytic

conversion into methanol. Currently,

methanol from biomass is projected to

cost about $0.85/gal, and with improved

technology, a cost of $0.50/gal could be

realized. Catalytic processing of pyrolytic

oils from biomass produces a mixture of

olefins that can be reacted with alcohols

to form ethers such as methyl tertiary butyl ether (MTBE) for use in reformulated

gasoline to reduce emissions. Costs could

be competitive today for olefins from MSW.

Because biofuels technologies require little

if any fossil fuel inputs, carbon is recycled

through their use, reducing substantially

the net amount of carbon dioxide released

to the atmosphere.

"Co-production of Methanol and

Power," William Weber, EPRI; Arden B.

Walters, Florida Power & Light

Company; and Samuel S. Tam, Bechtel

Group, Inc.

Integrated Coal Gasification Combined

Cycle (IGCC) is one of the emerging technologies for electric power generation from

coal. Under contract with Florida Power &

Light (FPL) and Electric Power Research

Institute (EPRI), Bechtel is to design an

IGCC/methanol co-production plant that is

suitable for utility operation of a baseloaded power plant. The potential benefits

of methanol co-production in an IGCC plant

are identified and quantified.

Shell and Dow gasifiers are selected for

this study only to illustrate the potential

effects of the dry-feed and slurry-feed gasification process on methanol production.

The combined-cycle power plant features

the GE Model MS-7001F gas turbines,

heat recovery steam generation (HRSG)

with steam reheat, and duct firing. The

fuel-grade methanol plant design is based

on Chem Systems’ Liquid Phase Methanol (LPMEOH) Process. Two operating

modes of the methanol plant are considered: the recycle mode (RM) and the

once-through mode (OTM).

Results from cases with the slurry-feed

gasifiers and OTM plant are presented in

this paper. They have indicated that methanol co-production can increase the equivalent availability of an IGCC plant to that

for a natural gas fueled combined cycle

plant. Methanol co-production can also reduce the risk of the lower than anticipated

gasifier availability.

"EPA’s Cost-shared Solar Energy

Program," Ronald J. Spiegel, EPA

The objective of this program is to establish and demonstrate solar energy

cost-shared commercialization projects to

demonstrate how they can be used to

displace fossil fuels. The program will also

have a major impetus to validate the ability of solar energy to be used as a pollution mitigation technology. Further, the

demonstrations will assist in removing obstacles to the marketplace for solar technologies by assisting in quantifying environmental concerns. This paper discusses

a project that has just commenced in the

area of photovoltaic demand-side power

supplies. Additional discussion is provided

relative to future projects that are being

contemplated.

"Photovoltaic Developments," Jack L.

Stone, National Renewable Energy

Laboratory

Photovoltaics, the direct conversion of

sunlight to electricity, is an environmentally pristine, renewable energy option currently used in a large number of international applications, principally nongrid-connected in remote locations. Examples include water pumping, communications, vaccine refrigeration, and village

power. Over the past 15 years, a very

aggressive research and development program carried out by DOE has continued

to improve photovoltaic performance and

reliability and has contributed to lower production costs. Along with these improvements have come a large number of new,

cost-effective uses, including larger power

installations in a utility environment. This

technical and economic progress is reviewed to represent the current status of

this renewable energy option. Near-term

plans for large-scale installations in the

U.S. are discussed along with the required

costs for competitiveness with conventional

electricity generation options.
8

"Advanced Energy Systems Fueled

from Biomass," Carol R. Purvis and

Keith J. Fritsky, EPA

The concentration of CO2

, a greenhouse

gas, is increasing by an estimated 0.5%

per year. CO2

 emissions from fossil fuel

combustion quadrupled between 1950 and

1980. Conversion of renewable biomass

to energy is CO2

, neutral and produces

lower SO2 and NOx

 emissions than fossil

fuel combustion.

EPA/AEERL is studying two biomass

conversion technologies: conventional

combustion in a boiler coupled with a

steam turbine system and gasification in a

gasifier coupled with an aeroderivative turbine system. In-house research is addressing the problems encountered in conventional systems with regard to emissions,

tube fouling, bed agglomeration, and low

thermal efficiency. Extramural research is

addressing the problems of advanced systems with regard to fixed/fluidized-bed gasifiers, alkali/particulate cleanup, gas compatibility with turbines, and system efficiency. The results will provide data for

owner/operators to improve system performance and for designer/developers to

demonstrate advanced systems. This research will help promote biomass-for-energy

as a global warming mitigation strategy

by focusing on a need to maximize biomass resources through increased utilization efficiency.

"Programs and Policy Impacts

Attributable to Regional Biomass

Program Woodstove Research

Efforts," Stephen Morgan, EPA

The decision by the CONEG Policy Research Center in the spring of 1985 to

embark upon a field evaluation of

woodstoves led to an ambitious and sophisticated 6-year research program that

has had profound impacts on the evolution of the industry. The initial interest in

United States

Environmental Protection Agency

Center for Environmental Research Information

Cincinnati, OH 45268

EPA/600/SR-94/008

Official Business

Penalty for Private Use

$300

BULK RATE

POSTAGE & FEES PAID

EPA

PERMIT No. G-35

Sue Philpott is with Acurex Environmental Corp., Durham, NC 27713.

Keith J. Fritsky is the EPA Project Officer (see below).

The complete report, entitled, "Proceedings: The 1992 Greenhouse Gas Emissions

and Mitigation Research Symposium," (Order No. PB94-132180/AS; Cost:

$61.00, subject to change) will be available only from:

National Technical Information Service

5285 Port Royal Road

Springfield, VA 22161

Telephone: 703-487-4650

The EPA Project Officer can be contacted at:

Air and Energy Engineering Research Laboratory

U.S. Environmental Protection Agency

Research Triangle Park, NC 27711

exploring the claims of manufacturers

about the efficiency, particulate emissions,

and creosote buildup in catalytic, catalytic

add-on, and non-catalytic “high tech”

woodstove models readily expanded to

undergird much of the conceptual thinking

that informed the EPA’s participatory regulations negotiations process engaging the

industry, the Agency and environmentalists. Since the publication of the EPA certification standards in 1987 and the laboratory testing methodology utilized to support the standard, the Northwest Regional

Biomass Program (NRBP)-sponsored research has moved on to test the field

durability of certified stoves. The early,

disappointing findings in that field testing

identified structural, design and materials

flaws that have directly contributed to improved stove designs in the second generation of certified stoves.