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OAR Box 1781 

Prepped by Ollie Stewart 

Document Number: 

15)11-1-7 

Docket Number: 

A-90-37 

Printed 10/29/2008 10:46:18 AM Sheet 15 of 142 
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t- I , U-l-7 

«*"""»«*> UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

\ OFFICE OF RESEARCH AND DEVELOPMENT 

| AIR AND ENERGY ENGINEERING RESEARCH LABORATORY 

\ sP RESEARCH TRIANGLE PARK, NORTH CAROLINA 27711 

DATE: September 14, 1993 

SUBJECT: Analysis on Landfill Gas Utilization^oxjhe Soon-to-be-Promulgated 

Clean Air Act Regulations forsMuFllcipal^lid Waste Landfills 

FROM: Frank TyfiWioUa 

D i recto/(MD-60) 

TO: Peter Preuss. Director 

Office of Science, Planning and Regulatory Evaluation (H-8105) 

This memo provides the results of AEERL's analysis to develop estimates 

of the benefits associated with the utilization of landfill gas that will result from 

the Clean Air Act (CAA) regulations being considered for municipal solid waste 

(MSW) landfills. A decision by OAR on the stringency level of the rule is 

expected to be made within the next few weeks. Once this decision is made, 

Work Group Closure will follow and then the package will be submitted into 

OMB review. This analysis was undertaken to provide additional information to 

OAR which will hopefully help in reaching a decision on the rule. 

This analysis was conducted in collaboration with your office and the 

Office of Air Quality Planning and Standards (OAQPS), the Office of Policy. 

Planning and Evaluation (OPPE), the Office of Atmospheric Programs (OAP), 

and the Department of Energy (DOE). The analysis undertaken was for the two 

stringency levels under consideration - 50 and 75 Mg of The impacts for the 

stringency levels of the regulation are the most recent set of impacts and were 

provided by OAQPS. This memo provides a set of tables with the results of this 

analysis and documentation of the information that was used. 

Table 1 provides estimates of baseline methane and the potential methane 

reduction from (MSW) landfills for the two stringency levels (50 and 75 Mg/yr) 

under consideration for the years 2000 and 2010. These years were chosen to 

correspond to the timeframe being considered for the National Action Plan to 

reduce greenhouse gas emissions. A distinction is made for those sites where 

recovery may exist with or without the rule (i.e., excluded) versus those sites 

where gas recovery would not be considered in absence of the rule (i.e., 

included). This distinction was determined as a result ofa analysis conducted by 

OAP in December (Memorandum from OAP to OAQPS, Landfill Rule Energy 
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Table 1. Estimated Methane Reductions for CAA Rule for Municipal Solid Waste 

Landfills - Total Emissions for New & Existing Landfills (Teragrams) 

4 , 

*SE*, 

Stringency Level 

50 mg/yr 

75 mg/yr 

Year 

Excluded 

4.2 

4.0 

2000 

Included 

4.3 

3.6 

Total 

8.5 

7.6 

Excluded 

5.3 

4.9 

2 

2010 

Included 

4.7 

4.0 

Total 

10.0 

8.9 

The baseline estimate by OAQPS of MSW landfill methane is 14 Tg in 2000. This 

estimate, when adjusted for the gas collection efficiency, is 18 Tg. 

The baseline estimate by OAQPS of (MSW) landfill methane is 16 Tg in 2010. This 

estimate, when adjusted for the gas collection efficiency, is 20 Tg. 

Table 2. Energy Value Available for Electricity Generation from New & Existing 

Landfills Affected by CAA Rule (Quads) 

Stringency Level 

50 mg/yr 

75 mg/yr 

Year 

Excluded 

0.22 

0.21 

1 

2000 

Included 

0.22 

0.19 

Total 

0.44 

0.40 

Excluded 

0.28 

0.25 

2 

2010 

Included 

0.24 

0.21 

Total 

0.52 

0.46 

The baseline estimate for 2000 (not adjusted for gas collection efficiency) is 0.73 

quads or 0.88 quads when adjusted for the gas collection efficiency. 

2

 The baseline estimate for 2010 (not adjusted for gas collection efficiency) is 0.83 

quads or 1.0 quads when adjusted for gas collection efficiency. 
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Recovery Cost Analysis, 12/16/92). This analysis was undertaken becau.se NMOC 

emissions are not directly correlated with methane emissions. Industry trends 

and information on market barriers were used to evaluate the potential amount of 

methane that may be utilized as a result of the rule. 

The estimate of baseline methane and potential methane reductions for the 

CAA rule for new and existing landfills are presented in Table 1. Tlie 

corresponding estimate of potential energy available for electricity generation is 

presented in Table 2. As you can see, the energy value in quadrillion Btus (i.e., 

quads) is 0.88 for the year 2000 and 1.0 for the year 2010 for the baseline 

estimate adjusted for the gas collection efficiency. We include both categories of 

sits (i.e., included and excluded) as well as the combined totals. 

The OAQPS has estimated 8.5 teragrams (Tg) of methane are reduced in 

2000 for the sum of the excluded and included sites in 2000 and 10 Tg of 

methane are reduced in 2010 for the 50 Mg/yr stringency level. This is equal to 

51 million tons of carbon equivalents (MMTCE) in 2000 and 60 MMTCE in 

2010. The 75 Mg/yr stringency level results in a reduction of 7.6 Ts of methane 

(46 MMTCE) in 2000 and^8.9 Tg of methane (53 MMTCE) in 20107 The 

estimates presented in Table 1 were calculated as described by docket item A-88-

09, IV-M-4, Methodology Used to Revise the Model Inputs in the Municipal Solid 

Waste Landfills Input Data Bases, 4/28/93. 

Since it is only those sites designated as "included" where there is potential 

for energy recovery as a result of the options under consideration, we have 

determined the potential electrical energy and associated by-product emissions. 

The OAQPS developed estimates of the amount of electricity generated by those 

landfills that are predicted to recover energy as a result of the rule. These 

estimates are presented in Table 3. Using the results from this table, we 

calculated the tons of carbon dioxide (CO2), sulfur dioxide (SO2), and nitrogen 

oxides (NOx) that would be generated if this same amount of energy were 

produced by conventional energy sources. The results are presented in Table 4. 

Tlie "marginal emission factors" that were used were developed by ICF 

Resources for the U.S. DOE, Office of Building Technologies, using ICF's 

National Integrated Planning Model, a detailed electric utility dispatch and 

capacity planning model. The underlying assumptions (e.g., electricity demand 

growth, fuel prices, etc.) are based on the forecasts and assumptions of the 

Annual Energy Outlook, 1993. The results of this study are documented in 

Impact Assessment of Advanced Equipment for the Building Sector, Electric 

Utility Impact Methodology, Final Report, Draft, Forthcoming. The marginal 

factors used in this report are weighted to reflect national average factors. The 
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««*• • 

Table 3. Estimated Electricity Production for New & Existing 

Landfills for the Sites Predicted to Use Energy Recovery* 

'Excludes sites determined to be profitable or already utilizing energy recovery 

( kWhxIO 9 ) 

Stringency 

Level 

50 mg/yr 

75 mg/yr 

Year 

New 

0.41 

0.21 

2000 

Existing 

6.3 

5.6 

Total 

6.7 

5.8 

New 

0.89 

0.80 

2010 

Existing 

5.8 

5.0 

Total 

6.7 

5.8 

Table 4. Emissions Generated if Energy Produced by Fossil Fuels for 

Energy Produced by Landfills Predicted to Use Energy Recovery (tons)* 

Stringency 

Level 

50 mg/yr 

75 mg/yr 

(tons) 

COaxlO6 

4.2 

3.6 

SO2X103 

1.3 

1.2 

NOxxlO3 

12 

10 

*For both new and existing landfills using marginal emission factors developed using information 

included in Attachment 2. The factors developed for 2005 were used based on a national 

weighted average. The emissions generated are the same for both 2000 and 2010. 

3 6 

Estimate of CO2 emissions in U.S. is 4,800 x 10 tons in 1988 (National Academy Press, 1991). 

b

 Estimate of total SOx emissions in U.S. is 23 x 10

 6 tons in 1991 (EPA, 10/92). 

° Estimate of total NOx emissions in U.S. is 21 x 10

 6 tons in 1991 (EPA, 10/92). 
P.6 

title page from this report and the marginal emission factors used to calculate the 

impacts in Table 4 are included as Attachment 1. 

Full credit can be taken for a savings in both the SO2 and CO2 emissions. 

There is a savings of 4.2 million tons of CO2 for the 50 Mg/yr stringency level 

and 3.6 million tons for the 75 Mg/yr stringency level for both the year 2000 and 

2010. There is a savings of 1.3 thousand tons of SO2 for the 50 Mg/yr stringency 

level and 1.2 thousand tons for the 75 Mg/yr stringency level. These SO2 savings 

may be used by electric utilities in reducing the compliance cost to meet the 

CAAA requirements for SO2 emissions. 

There will be an offset in the NOx emissions which needs to be considered 

between the NOx generated using the preaSent mix of conventional energy sources 

versus that generated utilizing landfill gas. However, data are insufficient at the 

present time to be able to calculate the NOx and CO emissions being generated by 

boilers, internal combustion engines and turbines being fueled with landfill gas. 

Research planned through the National Action Plan would result in data that will 

allow us to determine the offset in emissions. We think that there will be a 

savings in NOx but less than what is presented in Table 4. 

To illustrate the significance of the potential energy values presented in 

Table 2, we compared these values to the amount of energy used by electric 

utilities to generate electricity. This information is presented in Tables 5 and 6. 

From theaSe comparisons we used recent statistics published by DOE in January 

1993, Annual Energy Outlook with Projections to 2010. 

We recognize that the values presented in these tables make different 

assumptions about the extent of utilization of landfill gas. Unfortunately, barriers 

exist that discourage energy recovery. Some of the nontechnical barriers include: 

- unfavorable economics as a result of low energy costs for landfill gas to 

energy projects that generate or pipeline quality gas, 

- no near-by customer for direct gas use, 

- air permits for internal combustion engines, gas turbines and boilers not 

being approved for projects in nonattainment regions, 

- extensive permitting requirements in both attainment and nonattatinment 

regions resulting in high costs associated with complying with applicable 

Federal and State regulations, 
Table 5. Percentage of Landfill Methane to Annual 

Consumption of Coal by U.S. Electric Utilities 

(%) 

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*«* • 

Assumption Year 2000 2010 

Baseline estimate of landfill methane 

- w/o collection efficiency correction 

- w/collection efficiency correction 

4.5% 

5.4% 

5.1% 

6.2% 

Stringency Level (mg/yr) 

Estimate of landfill methane for new & 

existing sites that are "excluded"2 

Estimate of landfill methane for new & 

existing sites that are "included"3 

Estimates of total (excluded & included) 

methane to be controlled by regulatory 

option 

50 

1.40% 

1.40% 

2.70% 

75 

1.30% 

1.20% 

2.50% 

50 

1.70% 

1.50% 

3.20% 

75 

1.50% 

1.30% 

2.80% 

1

 In 1990, electric utilities consumed 16.2 quads of coal. 

2

 Excluded is defined as those sites where it is "profitable" to recover energy or projects 

already exist. These sites are predicted to utilize the gas in absence of the role. This 

was determined by OAP memo, 12/92. 

3

 Included is defined as those sites that may utilize the gas as a result of the rule. 

However, some sites may decide to flare the gas. 
Table 6. Percentage of Landfill Methane to Annual 

Consumption of Petroleum by U.S. Electric Utilities

 1 

(%) 

P.8 

Assumption Year 2000 2010 

Baseline estimate of landfill methane 

- w/o collection efficiency correction 

- w/collection efficiency correction 

60% 

68% 

72% 

81% 

Stringency Level (mg/yr) 

Estimate of landfill methane for new & 

existing sites that are "excluded" 

Estimate of landfill methane for new & 

existing sites that are "included" 

Estimated total (excluded & included) -

methane to be controlled by regulatory 

option 

50 

18% 

18% 

36% 

75 

17% 

15% 

32% 

50 

23% 

1 9% 

42% 

75 

20% 

17% 

37% 

1

 In 1990, electric utilities consumed 1.23 quads of petroleum. 

2

 Excluded is defined as those sites where it is "profitable" to recover energy or projects 

already exist. These sites are predicted to utilize the gas in absence of the role. This 

was determined by OAP memo, 12/92. 

3

 Included is defined as those sites that may utilize the gas as a result of the rule. 

However, some sites may decide to flare the gas. 
P.9 

8 

- difficulties in negotiating power contracts, 

- power contracts with utilities resulting in a minimization of the gas 

being recovered for utilization. 

There are other barriers which we have worked to document and are identified in 

an EPA report prepared by AEERL, Landfill Gas Energy Utilization: 

Technology Options and Case Studies. EPA-600/R-92-116, June 1992. Also two 

papers by Susan Thorneloe on my staff have described these issues and these are 

provided in Attachment 3. We have ongoing efforts in collaboration with the 

International Energy Agency (IEA) to identify both the technical and 

nontechnical barriers associated with utilization of landfill methane. Tliese 

factors impede the viability of landfill gas to energy projects and consequently 

discourage the utilization of landfill gas. 

We also would like to point out that ORD's research being conducted by 

AEERL to minimize some of the technical barriers associated with energy 

equipment. As you may be aware we are working to demonstrate the u.se of fuel 

cells to recover energy from landfill gas which will enhance the nation's ability to 

utilize landfill methane. Fuel cells have minimal by-product emissions as 

compared to internal combustion engines and turbines. They also have a higher 

energy efficiency (-40%) as compared to conventional technologies in use which 

approach -30%. Fuel cells are also better suited to smaller landfills and remote 

installations. This research will.result in helping to minimize some of the 

existing barriers that exist particularly in nonattainment areas where NOx and 

CO emissions are of concern. This research is also directed towards making 

advances in gas pretreatment processes for fuel cell application to landfill 

methane. 

Another project that we are coordinating through the IEA is on the. 

different philosophies both in the U.S. and Europe and gas pretreatment and 

energy equipment modifications for landfill gas to energy projects. Advances in 

technology are occurring and we are working to document the current state of 

technology. Different approaches are in use and have different tradeoffs. We see 

this work as well as our earlier work to be a direct benefit to landfill 

owner/operators responding to the CAA regulations. We would like to see the 

preamble of the regulation identify this research. 

To summarize, this rule will result in substantial savings to our global 

fossil fuel reserves. It will also result in a reduction of byproduct emissions as 

illustrated in Table 4. This regulation has a number of benefits including the 
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reduction of a potent greenhouse gas, emissions contributing to tropospheric 

ozone, toxics of concern to human health, and the reduction in the explosive 

potential of the gas when it migrates offsite or onsite. 

Landfill methane is a potential pollution prevention source. We think it is 

important that the decision makers for this regulation be made aware of the 

current barriers for landfill gas utilization. We think that the EPA needs to 

develop a methodology that will allow consideration of the overall environmental 

and energy benefits including the conservation of our global fossil fuel resources. 

There are tradeoffs between NOx and VOC reductions as well as CO and carbon 

emissions. Presently our existing regulatory structure does not evaluate these 

benefits or tradeoffs. Do not hesitate contacting me at (919) 541-2822 or Susan 

Thorneloe at (919) 541-2709 if you have any questions about the information 

provided in this memo. 

References -

U.S. DOE, Impact Assessment of Advanced Equipment for the Building Sector -

Electric Utility Impact Methodology, Final Report, August 1993. 

Memorandum. Methodology Used to Revise the Model Inputs in the Municipal 

Solid Waste Landfills Input Data Bases. April 1993. Docket Item IV-M-4, A-88-

09. 

U.S. DOE, Annual Energy Outlook 1993 with Projections to 2010, DOE/EIA0383(93), January 1993. 

Memorandum. Landfill Rule Energy Recovery Cost Analysis. From Kathleen B. 

Hogan, Chief and Cindy Jacobs, Modeling and Methane Reduction Branch, Global 

Change Division, OAP, December 16, 1992. 

U.S. EPA, National Air Pollutant Emission Estimates, 1900 -1991. EPA-454/R92-013. Prepared by Office of Air Quality Planning and Standards. October 

1992. 

U.S EPA, Landfill Gas Utilization: Technology Options and Case Studies, EPA600/R-92-116. Prepared by Air and Energy Engineering Research Laboratory, 

RTP, NC, 27711. June 1992. 

Thorneloe, S. A., "Landfill Gas Utilization - Options, Benefits, and Barriers'", 

Published in the Proceedings from The Second United States Conference on 

Municipal Solid'Waste Management, Arlington, VA, June 1992. 
P.11 

10 

Thorneloe, S.A. "Landfill Gas Utilization - Options and Economics" Published in 

the Proceedings from the Sixteenth Annual Conference by the Institute of Gas 

Technology on Energy from Biomass and Wastes, Orlando, FL, March 1992. 

National Academy Press. Policy Implications of Greenhouse Warming. 

Washington D.C. 1991 

Memorandum. Information on Landfill Methane. From Frank T. Princiotta, 

Director, AEERL to Peter Preuss.Director, OTTRS, February 22, 1990. 

2 Attachments 

cc: J. Brodrick, DOE 

D. Doll, OAQPS 

D. Drehmel, AEERL 

S. Durkee, OSPRE 

T. Eagles, OPAR 

A. Geswein, OSW 

B. Hangebrauck, AEERL 

K. Hogan, OAP 

J.. Kessler, OPPE 

K. C. Hustvedt, OAQPS 

J. Kilgroe, AEERL 

W. Lamason, OAQPS 

B. Landreth, RREL 

S. Lingle, OEETD 

B. Martin, AEERL 

M. Maxwell, AEERL 

L. Smith, OEPER 

R. Spiegel, AEERL 

S. Thorneloe, AEERL 

D. Trout, OEPER 
P.12 

&EPA 

ATTACHMENT / 

United Slates 

Environmental Protection 

Agency 

Research and 

Development 

EPA-600/R-92-U6 

i 

June 1992 

LANDFILL GAS 

ENERGY UTILIZATION: 

TECHNOLOGY OPTIONS 

AND CASE STUDIES 

Prepared for 

Office of Air and Radiation 

and 

Office of Policy, Planning and .Evaluation 

Prepared by 

Air and Energy Engineering Research 

Laboratory 

Research Triangle Park NC 27711 

Stt&fcWSW 
FOREWORD 

Landfill gas has been successfully used for energy at many locations in the U.S. and worldwide, providing 

economic, environmental, and other benefits. However, landfill gas energy uses are also relatively new, 

and technologies are far from "cut and dried." There are limitations and special considerations with 

landfill gas energy use; a number of landfill gas energy projects have experienced problems, or even 

failed entirely. There is current need for documentation of experience and consolidation of information in 

several areas regarding the use of landfill gas as a fuel. 

This repon reviews the various landfill gas energy uses, and their associated issues and constraints. It 

also presents case studies of six landfill gas energy projects in the U.S. The report's purposes Include 

• Presenting overviews of use and equipment options, and technical and other 

considerations with landfill gas energy applications. 

• Providing information on projects that illustrate common landfill gas energy uses. 

• Providing an awareness of limitations and potential pitfalls existing with landfill gas 

energy use. 

In addition to providing background on energy uses, it is anticipated that the report will help identify areas 

needing attention, for entities such as researchers and equipment manufacturers. It is also hoped that 

the report can provide information useful in identifying ways to facilitate the beneficial uses of landfill gas 

by reducing nontechnical barriers. 

The complexities of landfill gas energy uses are such that the discussions of many issues must be limited 

to overviews. Where detail is available elsewhere the report refers to available literature containing that 

:. information. This is also true for the case studies; these attempt to provide infonnation so that a typical 

reader wfth tome limited background will have a reasonable understanding of the operation, based on a 

: representative description of a particular energy application. This document is not intended to provide the 

7 degree of detail needed to design and operate a landfill gas energy facility. 

li The case studies rely on Information provided by many individual operators, equipment manufacturers, 

and others such as engineering firms. An effort has been made to verify statements and data as much as 

possible. In particular, all sections of the report have been reviewed by the providers of the original 

information and others with appropriate expertise. Background information is cited from literature and 

other sources considered reliable, and it has also been reviewed. 

PJG G640101A.A0W 
P.14 

ABSTRACT 

Combustible, methane-containing gas from refuse decomposing in landfills, or "landfill gas," can be fuel 

for a variety of energy applications. This report presents case studies of projects in the United States 

where it has been used for energy, tt also presents overviews of some of the important issues regarding 

landfill gas energy uses, including appropriate equipment, costs and benefits, environmental concerns, 

and obstacles and problems of such energy uses. 

With allowance for its properties, landfill gas can be used in much commercially available equipment that 

normally uses more conventional fuels such as pipeline natural gas. This includes equipment for space 

heating, boilers, process heat provision and electric power generation. Landfill gas energy uses, already 

significant, could increase based on estimates of the landfill gas that could be recovered, and providing 

that other factors, particularly economic ones, are favorable. Such energy uses have environmental and 

conservation benefits. 

Factors to be considered in using landfill gas for energy include contaminants, which can corrode 

equipment and cause other problems, and its lower energy content, resulting in moderate equipment 

derating. Other issues that are of normal concern for landfill gas, such as forecasting its recoverable 

quantity over time, and its efficient collection, also bear importantly on its use for energy. 

The case studies review landfill gas energy use at six sites in the U.S. The energy applications include 

electric power generation by reciprocating internal combustion engines, electric power generation by gas 

turbine, space heating, and steam generation in a large industrial boiler. Case study applications are 

considered to represent attractive candidate uses for implementation at additional U.S. landfill sites. The 

case studies present the relevant site features, background regarding the development of the case study 

project, equipment used, operating experience, economics, and future plans at the sites. Obstacles and 

problems at the sites are discussed. The case study sites exhibit wide variation in features such as cost 

and degree of operating difficulty experienced. Such variation is typical of landfill gas energy projects, 

which tend to be site specific. Literature containing infonnation on other relevant case studies, in both the 

U.S. and other countries, is also referenced. 

Important conclusions include 

• Landfill gas can be a satisfactory fuel for a wide variety of applications. Such uses 

have environmental and conservation benefits. Many types of energy equipment 

designed for "conventional" fuels can operate on landfill gas with outputs reduced by 

about 5 to 20 percent. 

• Allowances must be made for the unique properties of landfill gas and particularly its 

contaminants. Pitfalls possible in landfill gas energy applications include equipment 

damage due to such gas contaminants, and shortages resulting from over-estimation 

of its availability. 

• The degree of gas cleanup and the methods used vary widely; the necessary amount 

of cleanup and the optimum tradeoffs between cleanup stringency and the frequency 

ol maintenance steps (such as oil changes) are not well established. 

• Cost-to-benefit ratios can vary widely; at some sites they are excellent, while at others 

they are a major limiting factor. Economics are probably the most important laclor 

limiting landfill gas energy uses. Economics currently tend to preclude smaller scale 

uses, uses where electric power sale prices are low, and uses at remote sites lacking 

convenient energy applications or outlets. Much ol the landfill gas generated today is 

not used for energy because of economics. 

PJG G640101A.A0W iii 
P.15 

• Energy equipment emission limits in some U.S. locations may also restrict landfill gas 

energy use, despite an environmental balance sheet that generally appears to be 

positive. 

This report identifies technical areas where energy uses are likely to benefit from improvements. Some of 

these are alluded to above. This report also comments briefly on incentive, barrier elimination, and other 

approaches that may facilitate landfill gas use. Finally, for present and future landfill gas users, further 

detailed documentation of the problems experienced, and the results of approaches to them (both 

successful and unsuccessful), would be very helpful. 

This report was submitted by EMCON Associates, in fulfillment of subcontract 275-026-31-05 from 

Radian Corporation, as well as subcontract 93.3 from E.H. Pechan and Associates, and performed under 

the overall sponsorship and direction of the U.S. Environmental Protection Agency, Global Emissions and 

Control Division. This report covers a period from February 1991 to January 1992, and work was 

completed as of February 1992. 

PJG G640101A.A0W IV 
P.16 

FOREWORD || 

ABSTRACT Jll 

ACKNOWLEDGEMENTS jell 

CONVERSIONS Xlv 

1. INTRODUCTION AND BACKGROUND 1 

1.1 Landfills and Landfill Gas: General 1 

1.2 Composition of Landfill Gas 2 

1.3 Estimating the Gas Recoverable for Energy Uses .' 3 

1.4 Gas Extraction Systems 3 

1.5 Environmental and Conservation Aspects of Landfill 

Gas Energy Use 4 

1.6 Regulatory Issues 4 

2. USE OF LANDFILL GAS AS A FUEL—TECHNICAL ISSUES 5 

2.1 Gas Composition Analysis 5 

2.2 Corrosion Effects 5 

2.3 Particulates and Their Effects 6 

2.4 Gas Cleanup 6 

2.5 Dilution and Other Performance Reduction Effects 

With Landfill Gas 7 

2.6 Load Factor ("Use it or lose it") 8 

3. ENERGY APPLICATIONS AND EQUIPMENT 9 

3.1 Current Applications and Equipment 9 

3.1.1 Space heating (and cooling) 9 

3.1.2 Process heating and cofiring applications 10 

3.1.3 Boiler fuel 10 

3.1.4 Reciprocating internal combustion engines with 

electric power generation 10 

3.1.5 Gas turbines

 1 1 

PJG G640101A.A0W 
P.17 

CONTENTS 

3.1.6 Steam-electric 12 

3.1.7 Purification to pipeline quality methane 12 

3.2 Potential Future Technologies 12 

3.2.1 Fuel cells 12 

3.2.2 Compressed gas vehicle fuels 13 

3.2.3 Synthetic liquid fuels and chemicals 13 

4. COST AND REVENUE COMPONENTS 14 

4.1 Components of Cost and Income 14 

4.2 Cost Data: Examples 15 

4.2.1 Hypothetical generating facility example: 

Cost component ranges 15 

4.2.2 Reported electric facility capital costs: 

GAA Yearbook 15 

4.3 Other Economic Issues 17 

4.3.1 Revenue requirement for electric power 

generation 17 

4.3.2 Initial cost estimating 17 

4.3.3 Economic impediments to energy applications . . .17 

5. Case Studies 19 

5.1 Electric Power Generation and Space Heating Using 

Landfill Gas: Prince George's County, Maryland .19 

5.1.1 Introduction and general overview 19 

5.1.2 History of project implementation 19 

5.1.3 Landfill and landfill gas system 23 

5.1.4 Energy facility and equipment 23 

5.1.5 Environmental/emissions 27 

5.1.6 Operation and maintenance 27 

5.1.7 Economics ."3 

5.1.8 Discussion 29 

5.1.9 Calculation bases—energy use and financing 30 

5.2 Electricity Generation Using Cooper-Superior Engine 

at the Otay Landfill 31 

5.2.1 Introduction and general overview 31 

5.2.2 Otay landfill and landfill gas system 31 

5.2.3 Gas preprocessing and energy plant equipment 33 

PJG G640101A.A0W VI 
P.18 

afljMttai M 

CONTENTS 

5.2.4 Environmental/emissions 36 

5.2.5 Operation and maintenance 36 

5.2.6 Revenue and cost items 37 

5.2.7 Discussion 37 

5.3 Electric Power Generation Using Waukesha Engines at the Marina Landfill. . 38 

5.3.1 Introduction and general overview .38 

5.3.2 History of project 40 

5.3.3 Landfill and landfill gas extraction system 41 

5.3.4 Gas preprocessing and energy plant equipment 43 

5.3.5 Environmental/emissions .46 

5.3.6 Economics 47 

5.3.7 Operation and maintenance 48 

5.3.8 Discussion 48 

5.4 Electric Power Generation Using Gas Turbines at Sycamore Canyon Landfill. 49 

5.4.1 Introduction and general overview .49 

5.4.2 History of system implementation 51 

5.4.3 Landfill and landfill gas system 51 

5.4.4 Plant equipment: Gas preprocessing and energy 52 

5.4.5 Environmental 7 55 

5.4.6 Economics 55 

5.4.7 Operation and maintenance 56 

5.4.8 Discussion 56 

5.5 Landfill Gas Fueled Boiler: Raleigh, North Carolina 57 

5.5.1 Introduction and general overview 57 

5.5.2 History of project implementation 57 

5.5.3 Landfill and landfill gas system 59 

5.5.4 Energy equipment: Blower station, pipeline 

and boiler 60 

5.5.5 Performance 61 

5.5.6 Emissions 62 

5.5.7 Operation and maintenance 62 

5.5.8 Economics 63 

5.5.9 Discussion 63 

5.6 Electrical Power Generation Using Caterpillar Engines at 

the Central Landfill, Yolo County, California 63 

5.6.1 Introduction and general overview 63 

5.6.2 History of project implementation 65 

5.6.3 Landfill and landfill gas extraction system 66 

PJG G640101A.AOW VII 
P.19 

•<»-*.• 

CONTENTS 

5.6.4 Gas preprocessing and energy conversion equipment 68 

5.6.5 Performance and availability issues 69 

5.6.6 Environmental/emissions .71 

5.6.7 Operation and maintenance 71 

5.6.8 Economics 71 

5.6.9 Discussion 71 

5.7 Other Relevant Case Studies and Information 72 

5.8 Other Supplemental Literature 75 

6. REVIEW, COMMENTARY, AND CONCLUSIONS 76 

6.1 Conclusions 76 

6.2 Further Needs .77 

6.3 Facilitating Landfill Gas Energy Use 77 

REFERENCES .79 

Appendices 

Appendix A Estimating Gas Availability for Energy Uses A-1 

Appendix B Gas Extraction Systems B-1 

Appendix C Comments on Environmental and Conservation 

Aspects of Landfill Gas Energy Use C-1 

Appendix D Regulatory Issues with Landfill Gas Use D-1 

Appendix E Gas Composition Analysis E-1 

Appendix F Cost, Revenue, and Other Economic Components F-1 

Appendix G Site Plan, Otay Electrical Generation Facility G-1 

Appendix H Equipment Specifications, Otay Generation Facility. ..... . H-1 

Appendix I PG&E Power Purchase Rates, Marina 1-1 

Appendix J Cleaver-Brooks Boiler Specif ications J-1 

Appendix K United Kingdom Case Studies K-1 

Appendix L The Economics of Landfill Gas Projects in the 

United States L-1 

Appendix M Waste Management of North America, Inc. 

Landfill Gas Recovery Projects M-1 

Appendix N I-95 Landfill Gas to Electricity Project Utilizing 

Caterpillar 3516 Engines N-1 

PJG G640101A.A0W vm 

va*: 
P.20 

ILLUSTRATIONS 

Fioure Page 

1 Cost Per Kilowatt Versus Size 18 

2 Waukesha Engine - Generator Sets at Brown Station Road Landfill 20 

3 Energy Facility at Brown Station Road: Simplified Block Diagram 24 

4 Cooper-Superior Engine: Otay Landfill 32 

5 Electric Power Facility at Otay Landfill: Simplified 

Block Diagram " 34 

6 Marina Landfill Electrical Generating Facility: Trailers Housing 

Gensets 39 

7 Electric Power Facility at Marina Landfill: Simplified 

Block Diagram 44 

8 Sycamore Canyon Electric Generating Facility: Genset Building 50 

9 Gas Turbine/Electric Power Facility at Sycamore Canyon: 

Simplified Block Diagram 54 

10 Cleaver-Brooks Boiler at Plant of Ajinomoto, U.S.A 58 

11 Electrical Generation Facility at Yolo County Central Landfill 64 

12 Electrical Power Generation at Yolo County Central Landfill: 

Simplified Block Diagram 67 

PJG G640101A.A0W IX 
P.21 

ATTACHMENT / 

Landfill Gas Utilization -

Options, Benefits, and Barriers 

Susan A. Thorneloe (MD-63) 

Global Emissions and Control Division 

Air and Energy Engineering Research Laboratory 

U. S. Environmental Protection Agency 

Research Triangle Park, North Carolina 27711 

Presented at: 

The Second United States Conference on 

Municipal Solid Waste Management 

at 

Hyatt Regency Crystal City 

Arlington, VA 

June 3 - 5, 1992 
P.22 

LANDFILL GAS UTILIZATION - OPTIONS, BENEFITS, AND BARRIERS 

Susan A. Thorneloe 

Global Emissions and Control Division (MD-63) 

Air and Energy Engineering Research Laboratory 

United States Environmental Protection Agency 

Research Triangle Park, North Carolina 

Introduction 

Of the more than 6,000 active municipal solid waste (MSW) landfills in the United States (U.S.), 

there are 114 landfill gas (LFG) to energy projects. This paper describes the different options for 

LFG to energy projects and provides statistics on the U.S. LFG industry. This paper also 

provides an overview of the benefits associated with LFG utilization and identifies some of the 

current barriers in the U.S. that affect LFG utilization. The support for this research is from the 

U.S. Environmental Protection Agency's (EPA's) Global Climate Change Program on emissions 

and mitigation from landfills and other waste management facilities that produce greenhouse gases 

(Thorneloe, 1991). EPA's Air and Energy Engineering Research Laboratory (AEERL) has 

responsibility for EPA's research on emissions and mitigation for the major sources contributing to 

global climate change. Landfills are considered a significant contributor of methane (CH4) 

emissions and are being considered for control in negotiations regarding global climate change 

(U.S. EPA, 1989). 

Energy Utilization Options 

Landfill gas results from the anaerobicdecomposition of landfilled waste and can be a source of 

pollution as well as a resource. The composition of LFG is typically 50 to 55% CH4, 45 to 50% 

carbon dioxide (CO2), and <1% nonmethane organic compounds (NMOCs). The concentration of 

NMOCs can range from 240 to 14,300 ppm (U.S.EPA, 1991). LFG can also contain chlorinated 

and fluorinated compounds, particulate, water vapor, and occasionally air. Air infiltration is 

minimized because it (1) can kill the anaerobic bacteria that are needed to decompose organic 

refuse, (2) can cause landfill fires, and (3) dilutes the gas which increases the cost of recovering 

energy from the gas. 

The average heating value of LFG ranges from 17 to 20 MJ/dscm (450 to 550 Btu/dscf). Laidlaw 

Technologies, Inc., with responsibility for 12 LFG energy recovery projects, estimates that 

between 1,250 and 1,600 k\Ve of energy is generated from 28,000 scmd (1 million scfd) of LFG 

at 17 MJ/scm (450 Btu/scf) (Jansen, 1992). Consequently LFG is recovered to take advantage of 

the energy potential. This results in reducing emissions of CH4, NMOCs, and toxics. In addition, 

emissions are reduced at coal-fired power plants, and global resources of fossil fuel are conserved. 
P.23 

• __.-

The EPA's AEERL initiated a project in 1991 to document the options for LFG utilization. This 

work included gathering data on the operating and maintenance requirements, the financing and 

contractual arrangements, and "lessons learned" from the six sites included as case studies. A 

summary of this work (Thorneloe, 1992) includes a list of U.S. LFG to energy projects. The final 

report being prepared by Emcon Associates will contain detailed information for six U.Sv LFG to 

energy projects including capital and operating costs, process flow diagrams, and data regarding 

the environmental benefits of LFG utilization. This section provides a brief overview of the 

options for LFG utilization and a summary of the results of the EPA survey of LFG to energy 

projects. 

The EPA survey identified 114 LFG to energy projects in the U.S.(Thorneloe, 1992). Detailed 

results of this EPA survey are scheduled to be published this fall. This survey was conducted in 

coordination with the Solid Waste Association of North America (SWANA). Figure 1 provides a 

breakdown of the types of LFG to energy projects in the U.S. Most of the projects (i.e., -75%) 

generate electricity which is either used on-site or sold to a local utility. Of the projects generating 

electricity, approximately 344 MWe of power is being produced with 61 projects using internal 

combustion (IC) engines, 21 projects using gas-fed turbines, and 3 projects using steam-fed 

turbines. Pipeline quality gas is produced at six sites, and one site is processing LFG to produce 

diesel fuel. The most economical options for LFG utilization tend to be direct uses such as for 

process heat and as boiler fuel. Direct use of LFG as medium-heating value fuel is occurring at 21 

sites. 

Figure 2 provides a breakdown of die U.S. LFG to energy projects by state indicating the number 

of projects for states where there are at least three active LFG utilization projects. California has 

the largest number of LFG to energy projects partially due to state and local requirements resulting 

in the collection and control of gas. However, many LFG to energy projects have been initiated 

because of attractive economics particularly in the early 1980s when the price of energy helped 

make this more economical. Waste Management of North America has installed gas collection and 

controls as part of their operating policy. Waste Management has LFG to energy projects at 25 

sites with plans to start new projects at 5 additional sites (Markham, 1992). The Clean Air Act 

regulations proposed May 30,1991, are,expected to result in additional LFG utilization projects. 

Direct-Gas Use (Medium-Heating Value"). The options for medium-heating value LFG [i.e., -19 

MJ/ "dry" scm (-500 Btu/dscf)] include use as boiler fuel, space heating and cooling, and 

industrial heating/cofiring applications. The most typical use is as boiler fuel to produce steam. 

The majority of the 21 sites selling LFG for direct use are supplying fuel for boilers. This is a 

particularly attractive option since conventional equipment can be used with relatively little 

modification.. In addition, boilers tend to be less sensitive to LFG trace constituents and 

consequently less gas cleanup is required compared to the other alternatives. A limitation in the 

selection of this option is that a LFG customer must be relatively near, typically less than 1,600 to 

3,200 meters (1 to 2 miles) is considered desirable to avoid excessive costs and difficulties 

obtaining access. 

The other options for medium-heating value gas include industrial applications such as lumber 

drying, kiln operations, and cement manufacturing. An advantage of many industrial applications 
P.24 

•a 

& 

c 

o 

•a 

.3 

•a 

c 

UJ 

o 

IC Engines 

Med Heating-Value Gas 

Turbines 

p. High Heating-Value Gas 

0 1 0 2 0 30 40 50 60 70 

Number of LFG Projects 

Figure 1. Number of U.S. Landfill Gas Projects by Energy Utilization Option 

0 10 15 20 25 

Number of LFG Projects 

30 35 40 

Figure 2. Number of U.S. Landfill Gas Projects by State 

for those States with Three or More .Projects 
P.25 

is that fuel is required continuously, 24 hours per day. LFG can also be used as a supplemental 

fuel that meets a portion of the total demand. LFG to produce space heating is in limited use 

primarily due to piping costs and difficulty in matching up the LFG energy output with nearby user 

needs. Depending on climate and other factors, heat energy supplied by 14,000 scm/d (500,000 

scf/d) LFG corresponds to heating needs of an 18,600 to 93,000 m* (200,000 to 1,000,000 ft2) 

facility. The main difficulty with space heating is that loads tend to be variable over time, both 

during the day and by season. 

Electricity Generation. Of the 114 U.S. LFG to energy projects, 61 projects generate electricity 

using IC engines and 24 projects generate electricity using turbines. Of the 344 MWe of electricity 

produced at these sites, 51% is generated using turbines and 49% is generated using IC engines. 

The type of equipment is generally determined by the volume of gas available and the air pollution 

requirements of the area in which the project is located. The rule of thumb for the selection of 

engines versus turbines is that engine projects are typically used at sites where gas quantity is 

capable of producing 1 to 3 MWC. Turbines are typically used at sites producing more than 3 MWe 

(Jansen, 1992). Typically there are three to five engines per project and one to two turbines per 

project. The distribution of U.S. LFG to energy projects based on gross output is: 

Number of Projects Using: 

MW. 

1-5 

5-10 

10-15 

15-20 

20-25 

25-30 

30-35 

35-40 

40-45 

45-50 

Turbines 

12 

10 

1 

0 

0 

0 

0 

0 

0 

1 

IC Engines 

54 

3 

3 

1 

0 

0 

0 

0 

0 

0 

TOTAL 24 61 

Reciprocating IC engines drive electrical generators to produce electrical power which is typically 

sold to the local electric utility. Engines used in this application are sold by diree manufacturers -

Caterpillar, Cooper-Superior, and Waukesha. Each of the 3 manufacturers has in place more than 

20 engines at U.S. landfill sites (GRCDA, 1989). These manufacturers design engines that are 

specific to LFG applications (i.e., corrosion resistant). Typically, warranties that guarantee engine 

performance require the operator to agree to certain conditions regarding engine operation and 

maintenance. 

Reciprocating engines used for LFG applications may be either stoichiometric combustion or lean 

combustion engines. The "lean-bum" engines are turbocharged and bum fuel with excess air. The 

stoichiometrically carbureted or "naturally aspirated" engines have air in the fuel/air mix just 

sufficient to burn the fuel. The lean-bum engines are typically used where nitrogen oxides (NOx) 

and carbon monoxide (CO) emissions are of concern. Stoichiometric combustion can result in 

relatively high NOx emissions which can vary widely due to carburetor setting and other variables. 
P.26 

Another factor to consider is that there is a trade-off between low NOx emissions and die reduction 

of NMOCs. 

Gas-fed turbines are also used at landfills to generate electricity. Gas turbines take large amounts 

of air from the atmosphere, compress it, bum fuel to heat it, then expand it in die power turbine to 

develop shaft horsepower. This horsepower can be used to drive pumps, compressors, or 

electrical generators (McGee and Esbeck, 1988). Gas turbines are used at 21 U.S. landfills to 

produce 108 MWC of power. Waste Management of North America, Inc. has found that gas-fed 

turbines typically have parasitic energy losses of 17% of gross output as compared to 7% for IC 

engines. A factor to consider is that turndown performance is poor in comparison to that of IC 

engines. Turbines perform best when operated at full load, and difficulties can occur when 

operated at less than full load. In addition, trace constituents have been reported to cause 

corrosion, combustion chamber melting, and deposits on blades. However, these difficulties can 

be overcome as demonstrated by Waste Management of North America (Schlotthauer, 1991). 

Steam-fed turbines are in use at three sites to produce 64 MWe of power. The largest LFG to 

energy plant is the Puente Hills Energy Recovery from Gas facility (PERG), located at the Puente 

Hills Landfill in Whittier, California. This site began recovering LFG for energy utilization in 

November 1986. It is operated by the Los Angeles County Sanitation Districts. The facility 

consists of twin Zurn Industries, Inc. gas-fired steam generators. Each of die units fires 420,000 

scmd (10,300 scfm) of LFG, producing 95,340 kg (210,000 lb) of steam per hour at 9.3 MPa 

(1350 psig), heated to 540°C (1000°F). This steam drives a Fuji Electric Co. Ltd. turbine that 

generates approximately 50 MWe net, that is sold to Southern California Edison (Valenti, 1992). 

High-Heating Value Gas. Seven sites in the U.S. upgrade LFG to pipeline quality. This option 

was considered more attractive in the early 1980s when the price of oil and natural gas helped make 

this more economical. The sites that are producing pipeline quality gas were initiated in the early 

1980s when gas prices on a heating-value basis were comparable with those of oil. These sites 

have an average LFG flow rate of 142,000 scmd (5 million scfd) with the lowest gas flow rate 

being 31,150 scmd (1.1 million scfd) and the highest being 269,000 scmd (9.5 million scfd). 

Stringent cleanup technology is applied to purify the gas to pipeline quality by removing the trace 

constituents and CO2. Similar to the medium-heating value applications, a nearby natural gas 

pipeline is needed. The largest operator of facilities producing pipeline quality gas from LFG is 

Air Products and Chemicals, Inc. Low natural gas prices in the late 1980s forced several previous 

projects to shut down, and continue to inhibit the development of new high-heating value projects 

in the U.S. However, sites in the Netherlands are finding more favorable economics (Scheepers, 

1991). 

A site that began operation last year in Pueblo, Colorado, is producing liquid diesel fuel from 

LFG. This site is operated by Fuel Resources Development, Inc. and began producing commercial 

product in January. A second site in the U.S. may be used to produce vehicular fuel from LFG. 

The South Coast Air Quality Management District has awarded a contract to demonstrate a process 

for producing methanol from LFG. The site selected for this demonstration is the BKK landfill, 

where there was co-disposal of hazardous and municipal waste. TeraMeth Industries is 

responsible for the demonstration, and research is being coordinated with the EPA. The 

demonstration is anticipated to begin in 1993. 
P.27 

Other Options for Landfill Gas. Fuel cells are a potentially attractive option for LFG because of 

higher energy efficiency, availability to smaller as well as larger landfills, and recognition for 

minimal byproduct emissions. Other advantages include minimal labor and maintenance, and 

(because there are no moving parts) the noise impact is minimal. Hydrogen from the landfill gas is 

combined electrochemically with oxygen from the air to produce dc electricity and by-product 

water. The fuel cell is designed for automatic, unattended operation, and can be remotely 

monitored. The EPA's AEERL initiated a project in 1991 to demonstrate the use of fuel cells for 

LFG application. The type of fuel cell being demonstrated is a commercially available 200 kWe 

phosphoric acid fuel cell power plant. The 1-year full-scale demonstration is scheduled for 1993. 

The major issue associated with this demonstration is designing a LFG cleanup process that will 

remove the trace constituents from the LFG and at the same time not be cost prohibitive. Since the 

composition of LFG varies over time, designing a process that can allow for this variability is 

difficult. A cleanup process has been proposed and is to be evaluated later this year. The fuel 

pretreatment system incorporates two stages of refrigeration combined with three regenerable 

adsorbent steps (Sandelli, 1992). It is hoped that, if the EPA demonstration of the use of fuel cells 

is successful, more landfill owner/operators will consider fuel cells as an option for LFG 

utilization. Given the higher energy efficiency and potential for minimal byproduct emissions, fuel 

cells may be the most attractive option for areas where there are stringent requirements for NOx and 

CO emissions. 

Benefits of Landfill Gas Utilization 

The five major health and welfare effects of air emissions from MSW landfills are (1) explosion 

hazards, (2) global warming effects from CH4 emissions, (3) human health and vegetation effects 

caused by ozone formed from NMOCs, (4) carcinogenicity and other possible noncancer health 

effects associated with specific MSW landfill emission constituents, and (5) odor nuisance. The 

first concern, the explosive potential of LFG, has resulted in 40 cases of gas migration in the U.S. 

which have resulted in explosions and fires. Of these 40 cases, 10 resulted in injuries and death 

(U.S.EPA, 1991). The second concern is the contribution of landfill CH4 to global warming. 

Landfills are a significant source of CH4, ranking third in anthropogenic sources after rice paddies 

and ruminants (Peer et al., 1992, Khalil and Rasmussen, 1990). A third concern is the 

contribution of NMOCs to tropospheric ozone which affects human health and vegetation. The 

EPA has estimated that roughly 1% (i.e., 260,000 Mg/yr) of the NMOC emissions from stationary 

sources in the U.S. are emitted by MSW landfills. Toxic constituents typically found in LFG 

include vinyl chloride, toluene, and benzene which may contribute to possible cancer and noncancer health effects. The fifth concern is the odor nuisance associated with LFG. Because of the 

health and environmental concerns, the EPA has designated "MSW landfill emissions" as a 

pollutant to be regulated under Sections 111(b) and 111(d) of the Clean Air Act. The EPA has 

proposed Emission Guidelines for existing landfills and New Source Performance Standards for 

new landfills (Federal Register, 1991). The regulations are scheduled to be promulgated this Fall. 

The regulatory alternative proposed by the Qean Air Act regulations would result in requiring 621 

landfills to collect and control MSW landfill emissions (p. 24480, Federal Register, 1991). 

.Although the rule does not require utilization of the gas, it is hoped that the sites affected by these 

regulations will consider LFG to energy as opposed to flaring the gas. The use of energy recovery 
P.28 

for the control of MSW landfill air emissions will result in decreased emissions of CH4, NMOCs, 

and toxics. In addition, emissions are reduced at coal-fired power plants, and global resources of 

fossil fuel are conserved. Although increased CO2 emissions are being traded off for reduced CH4 

emissions, this is a net benefit due to the difference in the radiative forcing capacity between CO2 

and CH4. The radiative forcing capacity of CH4 to CO2 on a molecular basis is 21 times that of 

C02 (p. 53, IPCC, 1990). 

There are also benefits associated with the development of an alternative source of energy which 

results in decreased emissions at coal-fired power plants, conservation of fossil fuel resources, and 

reduced dependence on imported oil. In addition, LFG utilization can result in a substantial cost 

savings to public entities that own the landfill as well as royalty payments. For example, Pacific 

Energy - who has developed 25 LFG energy projects - has paid out $13 million in royalties, 

mosdy to public entities. On average, Pacific Energy's projects are in the sixth year of operation 

under anticipated twenty-year project lives (Wong, 1992). Other economic benefits include the 

purchase of goods and services. In 1991, Pacific Energy purchased over $4 million in outside 

goods and services to support its LFG projects plus a payroll of >$3 million. LFG to energy 

projects tend to be capital intensive and are typically built on what is considered undevelopable 

acreage. Pacific Energy's eight LFG to energy projects in California pay >$350,0O0 per year in 

property taxes in California and require few public services (Wong, 1992). 

Barriers to Landfill Gas Utilization 

A major factor in helping to encourage LFG to energy projects is the Public Utility Regulatory 

Policy Act (PURPA). It guarantees that utilities purchase power that was generated from landfills 

at a price related to the costs that utility would experience to produce the same amount of power. 

Although this guarantees a purchaser for the power, the power sale revenues may be low if the 

utilities' own generating costs are low. In addition, tax credits have been available that also 

encourage renewable energy projects, such as LFG utilization. However, current trends are 

toward lower energy prices, reduced tax incentives, and increasing environmental liability. 

Although there are more than 6000 landfills in the U.S., there are less than 120 LFG to energy 

projects. During the oil crisis in the 1970s/1980s when the price of oil increased from $6-8 per 

barrel to $35 per barrel, there was much more interest in developing alternative sources of energy, 

including utilization of landfill gas. With the current prices of energy, it is much more difficult to 

find projects that are economical. More than 30 U.S. projects have had to cease operation due to 

economics. Many of the projects that were upgrading to pipeline quality are no longer in operation 

primarily due to economics. The pipeline cost can be excessive which is why sites tend not to 

transport the gas farther than 1,600 to 3,200 meters (1 to 2 miles). 

Laidlaw Technology Inc. suggests that "successful" LFG projects need to be over 1 MWe and have 

an electrical price of at least $0.06-0.07/kWh including any capacity payments. Royalties should 

not exceed 12.5% at this energy pricing (Jansen, 1992). Laidlaw also suggests that, if higher 

royalties are offered, the percentage should be a function of energy pricing over and above the base 

energy rate as inflation occurs. The early LFG projects were based on an established firm price for 

net energy which provided a substantial degree of security to developers. Contracts for many LFG 

projects do not allow for fluctuations in energy rates and costs. Revenues for energy sales are 
P.29 

usually based on prices of the "competition" of equivalent energy sources (e.g., petroleum 

products). Since the value of the energy base commodity can fluctuate, this can impact profit 

Administration and development costs have increased as revenues have decreased. Administrative 

and development costs include legal fees, permit applications, and contract negotiations including 

gas lease agreements and power purchase agreements. These costs may vary widely depending on 

the environmental issues, development considerations, and regulatory requirements. John Pacey 

of Emcon Associates has found mat these costs can vary from $30,000 to $1,000,000 per kWh for 

a 1 MWe LFG energy project. 

Tax credits are benefits proportional to gas energy delivery which were legislated by Congress 

(Section 29 of die IRS Code) in 1979 to encourage non-fossil fuel use. These credits are a direct 

offset to taxes and can only be used to offset a profit. The tax credits will extend to the year 2003 

and are allowable for extraction systems installed prior to die end of die year 1992. However, the 

most recent version of the tax bill being considered by Congress does not provide an extension for 

these tax credits. Robert F. Hatch of Cambrian Energy Systems - whose company has been 

involved in arranging financing for many U.S. LFG to energy projects - thinks that many of the 

projects would not be in existence if the tax credits were not available. Some projects today are 

financed only because of the tax credits since energy prices are relatively low. The tax credits help 

promote the development of a domestic resource as opposed to using foreign oil (Hatch, 1991). 

These tax credits help to encourage LFG to energy projects and also help municipalities defray the 

cost of environmental regulations. 

Another banier to LFG utilization can be environmental regulations. Unfortunately, the overall 

environmental benefit of utilizing LFG is not necessarily considered, let alone energy and 

economic benefits. George Jansen of Laidlaw Technologies is finding tiiat the cost of condensate 

disposal is becoming a major expense. The condensate is formed when the gas is compressed. 

The LFG condensate is being classified as a hazardous waste which requires disposal at a Subtitle 

C facility. This cost [i.e., $0.18/L (~$0.70/gal)] can be significant for a site where lean-bum 

engines or turbines are used as compared to the use of flares where minimal condensate is collected 

(3,800 L/day (1000 gpd) for lean-bum engines or turbines versus 760 L/day (200 gpd) for flares) 

(Jansen, 1992). 

Some LFG energy industry experts have found that the air, water, and solid waste agencies have 

conflicting goals. LFG energy projects have been forced to shut down due to concerns for byproduct emissions of NOx and CO. In California last year, 48 pieces of state legislation affecting 

solid waste were enacted (SWANA, 1992). Priorities often appear to conflict. There has been 

extensive coordination between the EPA Offices responsible for the Subtitle D regulations (e.g., 

Office of Solid Waste) and the proposed CAA regulations (e.g., Office of Air Quality Planning 

Standards) for MSW landfills to ensure that these regulations are complementary. However, 

additional effort appears needed to evaluate what can be done to help encourage and promote LFG 

to energy projects. 

Conclusions 

U.S. LFG to energy projects are currently recovering approximately 1.2 million tonnes of CH4 

and producing 344 MWe of power. The proposed CAA regulations for MSW landfill air 

emissions are expected to result in additional emission reductions ranging from 5 to 7 million 

8 
P.30 

tonnes of CH4. Utilization of LFG for those sites affected by die proposed CAA regulations has 

the potential to result in increased benefits to our economy, energy resources, and global 

environment. The utilization of alternative energy sources such as LFG extends our global fossil 

fuel resources. Not only are emissions direcdy reduced when LFG is collected and recovered for 

utilization, but emissions are also indirecdy reduced when secondary air emission impacts 

associated witii fossil fuel use are considered. 

References 

1. Federal Register. Vol 56. No. 104. May 30,1991, pp. 24468 - 24528. 

2. GRCDA/SWANA. "Engine and Turbine Panel Presentations." Proceedings from the 

GRCDA 9th International Landfill Gas Symposium, 1989. 

3. Hatch, R.F. "The Federal Tax Credit for Non-Conventional Fuels: Its Status and Role in 

the Landfill Gas Industry." Proceedings from SWANA's 14th Annual International 

Landfill Gas Symposium, 1991. 

4. Intergovernmental Panel on Climate Change. "Climate Change - The IPCC Scientific 

Assessment." World Meteorological Organization/United Nations Environment 

Programme. Edited by J.T. Houghton, G.J. Jenkins, and J.J. Ephraums, 1990. 

5. Jansen. G.R. "The Economics of LFG Projects in the United States." Presented at die 

Symposium on LFG/Applications and Opportunities in Melbourne, Australia, February 27, 

1992. 

6. Khalil, M.A.K. and R.A. Rasmussen. "Constraints on the Global Sources of Methane and 

an Analysis of Recent Budgets." Tellus, 42B, 229-236, 1990. 

7. Markham, M.A. "Landfill Gas Recovery to Electric Energy Equipment: Waste 

Management's 1991 Performance Record." Proceedings of SWANA's 15th Annual 

Landfill Gas Symposium, 1992. 

8. McGee, R.W. and D.W. Esbeck. "Development, Application, and Experience of 

Industrial Gas Turbine Systems for LFG to Energy Projects." Published in die 

Proceedings of GRCDA's 11th Annual International LFG Symposium. March 1988. 

9. Peer, R.L., S.A. Thorneloe, and D.L. Epperson. "A Comparison of Methods for 

Estimating Global Methane Emissions from Landfills." Chemosphere, 1992 (Ln Press). 

10. Sandelli, G.J. "Demonstration of Fuel Cells to Recover Energy from Landfill Gas." EPA600-R-92-007 (NTIS PB92-137520), January 1992. 

11. Scheepers, M.J.J. "Landfill Gas in the Dutch Perspective." Published in Proceedings of 

die Third International Landfill Symposium, Sardinia, October 1991. 
P.31 

««* • 

12. Schlotdiauer, M. "Gas Conditioning Key to Success in Turbine Combustion Systems 

Using Landfill Gas Fuels." GRCDA/SWANA's 14th Annual Landfill Gas Symposium in 

San Diego, CA. Published in the Proceedings from the Symposium. March 1991. 

13. SWANA. List of Solid Waste Legislation Enacted in 1991.1992. 

14. Thomeloe, S A. "Landfill Gas RecoveryAJtilization - Options and Economics." Published 

in Proceedings of die Sixteenth Annual Conference by die Institute of Gas Technology on 

Energy from Biomass and Wastes. March 1992. 

15. Thomeloe, S.A. "U.S. EPA's Global Climate Change Program - Landfill Emissions and 

Mitigation Research." Published in Proceedings of die Third International Landfill 

Symposium, Sardinia, October 1991. 

16. United States Environmental Protection Agency. "Air Emissions from Municipal Solid 

Waste Landfills - Background Information for Proposed Standards and Guidelines." EPA450/3-90-01 la (NTIS PB91-197061), March 1991. 

17. United States Environmental Protection Agency, Office of Policy, Planning and 

Evaluation. Policy Options for Stabilizing Global Climate. Draft Report to Congress. 

February 1989. 

18. Valenti, M. "Tapping Landfills for Energy." Mechanical Engineering, Vol. 114, No. 1, 

January 1992. 

19. Wong, F.P. "Alternative Energy & Regulatory Policy: Till Deaui Do We Part." Presented 

at AWMA Conference on "Cooperative Clean Air Technology - Advances Uirough 

Government and Industrial Partnership" in Santa Barbara, CA, March 21 - April 1,1992. 

10 
ATTACHMENT / 

Landfill Gas Recovery/Utilization 

Options and Economics 

Susan A. Thorneloe (MD-63) 

Global Emissions and Control Division 

Air and Energj Engineering Research Laboratory 

U. S. Environmental Protection Agency 

Research Triangle Park, North Carolina 27711 

Presented at: 

The Sixteenth Annual Conference 

by the Institute of Gas Technology 

on 

Energy from Biomass and Wastes 

Orlando, Florida 

March 5, 1992 
P.33 

LANDFILL GAS RECOVERY/UTILIZATION 

OPTIONS AND ECONOMICS 

Susan A. Thomeloe 

Global Emissions and Control Division 

Air and Energy Engineering Research Laboratory 

United States Environmental Protection Agency 

Research Triangle Park, Nonh Carolina 27711 

ABSTRACT 

The decomposition of landfilled waste results in a gas which can be a source of 

pollution as well as a resource. Of die more than 6,000 active municipal solid waste 

landfills in the United States (U.S.), there are 114 landfill gas 07-FG) energy projects. This 

paper describes the options and economics for LFG utilization, as well as ongoing research 

associated with encouraging/facilitating energy recovery from LFG. The health and 

environmental concerns are described as well as the economic, environmental, and energy 

benefits associated with LFG utilization. Six case studies are also provided to illustrate die 

options for LFG utilization. In addition, the results of a recent EPA survey of U.S. LFG 

utilization are provided. 

The Environmental Protection Agency (EPA) research that is described in this 

paper was conducted as pan of EPA's Global Climate Change Program on emissions from 

landfills and other waste facilities that contribute to global climate change (Thomeloe, 

1991). EPA's Air and Energy Engineering Research Laboratory (AEERL) has 

responsibility for EPA's research on emissions and mitigation for the major sources 

contributing to global climate change. 
P.34 

LANDFILL GAS RECOVERYAJTILIZATION 

OPTIONS AND ECONOMICS 

INTRODUCTION 

LFG is generated from the anaerobic decomposition of landfilled biodegradable 

waste. The composition of the gas is typically 50 to 55% metiiane, 45 to 50% carbon 

dioxide, and <1% nonmethane organic compounds (NMOCs). The concentration of 

NMOCs can range from 240 to 14,300 ppm (EPA, 3/91). LFG can also contain 

chlorinated and fluorinated compounds, particulate, water vapor, and occasionally air. Air 

is present from air intrusion into the landfill (i.e., it does not result from die anaerobic 

decomposition of wastes). There are economic incentives as well as safety considerations 

to operate the gas extraction wells so that air intrusion is minimized. Air intrusion can (1) 

kill the anaerobic bacteria that are needed to decompose organic refuse and (2) cause a 

landfill fire. Air infiltration is also minimized because it dilutes die gas and increases the 

cost of recovering energy from the gas 

The average heat content of LFG ranges from 17 to 20 MJ/dscm (450 to 550 Btu/dscf). 

Laidlaw Technologies, Inc., with responsibility for 12 LFG energy recovery projects, 

estimates that between 1,250 and 1,600 kWe of energy is generated from 28,000 scmd (1 

million scfd) of LFG at 17 MJ/scm (450 Btu/scf) (Jansen, 1992). Consequently LFG is 

recovered to take advantage of the energy potential. This results in reducing emissions of 

methane, NMOCs, and toxics. In addition, emissions are reduced at coal-fired power 

plants, and global resources of fossil fuel are conserved. 

The environmental and health concerns associated with municipal solid waste 

(MSW) landfills have been well documented. In die U.S., EPA has documented 40 cases 

of gas migration resulting in explosions and fires. Of these 40 cases, 10 resulted in 

injuries and deatii (EPA, 3/91). The metiiane is also a concern because of its contribution 

to global warming. Landfills are a significant source of methane, ranking third in 

anthropogenic sources after rice paddies and ruminants (Peer et al., 1992, Khalil and 

Rasmussen, 1990). A third concern with LFG emissions is the contribution of NMOCs to 

tropospheric ozone which affects human healtii and vegetation. The EPA has estimated 

diat roughly 1% (i.e., 260,000 Mg/yr) of the NMOC emissions from stationary sources in 

die U.S. are emitted by MSW landfills. Toxic constituents typically found in LFG include 

vinyl chloride, toluene, and benzene. The toxic constituents may contribute to possible 

cancer and non-cancer healtii effects. A fifth concern is the odor nuisance associated witii 

LFG. Because of die health and environmental concerns, the EPA has designated "MSW 

landfill emissions" as a pollutant. The EPA has proposed Emission Guidelines for 

existing landfills and New Source Performance Standards for new landfills (F.R., 5/91). 

The regulations are scheduled to be promulgated this Fall. 

The regulatory alternative proposed by die Gean Air Act regulations would result 

in requiring 621 landfills to collect and control MSW landfill air emissions, (p. 24480, 

F.R., 5/91). It is hoped that the sites affected by these regulations will utilize the gas as 

opposed to flaring the gas. The use of energy recovery for the control of MSW landfill 

air emissions will result in decreased emissions of metiiane, NMOC, and toxics. In 

addition, there are benefits associated with die development of an alternative source of 

energy which results in decreased emissions at coal-fired power plants and a decreased use 

of fossil fuels. The focus of this paper is to identify die options for LFG gas utilization 

and provide an overview of the economics associated with each option. Case studies are 

presented to illustrate the options for LFG utilization. 
P.35 

Enprgv Utilization Options 

A recent EPA survey identified 114 LFG energy recovery projects in the U.S. The 

results from this survey are summarized in Table I. Detailed results of ihis EPA survey 

are scheduled to be published this summer. This survey was conducted in coordination 

with the Solid Waste Association of North America and used the results of recent U.S. LFG 

surveys (Berenyi and Gould, 1991, Waste Age, 1990). Only sites that arc actually 

operating LFG energy projects are included in Table 1. 

Figure 1 provides a breakdown of die type of energy projects in the U.S. Most of 

the projects (i.e., -75%) generate electricity which is either used on-site or sold to a local 

utility. Of the projects generating electricity, approximately 344 MWe of power is being 

produced with 61 projects using internal combustion (IC) engines, 21 projects using gasfed turbines, and 3 projects using steam-fed turbines. Pipeline quality gas is produced at 6 

sites, and 1 site is processing LFG to produce diesel fuel. The most economical options 

for LFG utilization tend to be direct uses such as for process heat and as boiler fuel. 

Direct use of LFG as medium-heating value fuel is occurring at 21 sites. 

Figure 2 provides a breakdown of tiie U.S. LFG projects by state indicating the 

number of projects for states where there are at least three active LFG utilization projects. 

California has the largest number of LFG projects partially due to state and local 

requirements resulting in the collection and control of gas. However, many LFG energy 

projects have been initiated because of attractive economics particularly in the early 1980s 

when the price of energy helped make this more economical. Waste Management of 

North America has installed gas collection and controls as part of tiieir operating policy. 

Waste Management has LFG energy recovery projects at 25 sites with plans to start new 

projects at 5 additional sites. The Clean Air Act regulations proposed May 30, 1991, arc 

expected to result in additional LFG utilization projects. 

Direct-Gas Use (Medium-Heating Value). The options for medium-heating value 

LFG (i.e., -19 MJ/dscm (~500'Btu/dscQ) include use as boiler fuel, space heating and 

cooling, and industrial heating/cofiring applications. The most typical use is as boiler fuel 

to produce steam. The majority of the 21 sites selling LFG for direct use are supplying 

fuel for boilers. This is a particularly attractive option since conventional equipment can 

be used with relatively little modification. In addition, boilers tend to be less sensitive to 

LFG trace constituents and consequently less gas cleanup is required compared to the 

other alternatives. A limitation in the selection of this option is that a LFG customer must 

be relatively near, typically less than 1,600 to 3,200 meters 

(1 to 2 miles) is considered desirable. 

The otiier options for medium-heating value gas include industrial applications 

such as lumber drying, kiln operations, and cement manufacturing. An advantage of 

many industrial applications is thai fuel is required continuously, 24 hours per day. LFG 

can also be used as a supplemental fuel that meets a portion of the total demand. LFG to 

produce space heating is in limited use primarily due to piping costs and difficulty in 

matching up the LFG energy output with nearby user needs. Depending on climate and 

otiier factors, heat energy supplied by 14,000 scmd (500,000 scfd) LFG corresponds to 

heating needs ofa 18.600-93,000 m* (200,000 to 1,000,000 sq ft) facility. The main 

difficulty with space heating is that loads tend to be variable over time, both during the 

day and by season. One of die case studies, however, demonstrates the successful use of 

LFG for producing space heating. 

Electricity Generation. Of the 114 U.S. LFG energy recovery projects, 61 projects 

generate electricity using IC engines and 24 projects generate electricity using turbines. 

Of the 344 MWe of energy produced at these sites, 50% is generated using turbines and 

50% is generated using IC engines. The type of equipment is generally determined by the 

volume of gas available and die air pollution requirements of the area in which the project 
TABLE 1. U.S. LANDFILL GAS ENERGY PROJECTS USEPA. Thomeloe, 5/7/92 

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

Landfill Name 

Northslde 

Huntsvllle 

Olinda 

Burbank 

Temescal Road 

Duarte (*) 

Southeast Regional 

Industry Hills 

Altamont 

Mountain Gate 

Toyon Canyon 

Monterey Regional 

Acme 

Marsh Road 

Mountain View 

American Canyon 

Coyote Canyon 

Oxnard Power 

Station (") 

Palo Alto 

Spadra 

Palos Verdes 

Locator. (City) 

Birmingham 

Huntsvllle 

Brea 

Burbank 

Corona 

Duarte 

Fresno 

Industry 

Livermore 

Los Angeles 

Los Angeles 

Marina 

Martinez 

Menlo Park 

Mountain View 

Napa County 

Orange County 

Oxnard 

Palo Alto 

Pomona 

Rolling Hills 

Estates 

Locator) 

(Stale) 

AL 

AL 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

22 I Sacramento : Sacramento

 ! CA 

Use ot Landfill gas 

Pipeline Quality Gas 

Direct Gas User - Boiler 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Direct Gas User - Med Btu 

Electricity Gen - Gas Turbine 

(2) 

Direct Gas User - Boiler 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Direct Gas User - Med Btu 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - Steam Fed 

Turbine/Direct Use In Boiler 

Electricity Gen - Steam Fed 

Turbine/Direct Use In Boiler 

Date Gas 

Recovery 

Began 

Apr-88 

May-90 

Nov-84 

Aug-88 

Jan-86 

Oc»-87 

Feb-89 

Feb-81 

May-89 

Nov-84 

Dec-85 

Dec-83 

Apr-82 

Jan-83 

Dec-85 

Dec-85 

Feb-89 

Mar-85 

Apr-90 

Feb-90 

Mar-88 

2.7 

2.3 

3.0 

4.4 

1.0 

0.5 

0.7 

0.5 

2.0 

5.0 

4.0 

0.9 

1.7 

1.4 

2.2 

0.8 

14.4 

3.5 

0.8 

4.3 

11. 0 

Gross 

Energy 

RecoVd 

(MW) 

NA 

NA 

5.7 

0.8 

2.3 

1.6* 

0.7 

NA 

6.0 

NA 

10.0 

1.2 

NA 

2.0 

3.5 

1.5 

20.0 

5.1 

1.1 

5.0 

9.0 

Total 

landfill 

Acreage 

100 

45 

135 

86 

90 

33 

70 

150 

225 

80 

90 

478 

270 

160 

300 

122 

300 

140 

80 

210 

173 

Devoted 

IMIWM 

Recovery ' 

(acres) 

80 

12 

135 

24 

9 0 

33 

70 

150 

225 

80 

90 

60 

270 

100 

200 

70 

300 

140 

60 

210 

173 

Direct Gas User - Boiler 9Q ! 1 Q! N A 113 ; 4Q 

Refuse 

Buried 

OnSite 

(ml.T) 

5.8 

0.5 

12.0 

1.4 

4.0 

1.6 

2.0 

1.5 

14.3 

10.0 

16.0 

3.7 

5.0 

4.0 

3.0 

•> 

50.0 

2.7 

2.5 

9.0 

18.0 

2.6 

LFG Dovotopor/Operator 

Birmingham Gas Resources 

The Magulre Group Inc. 

GSF Energy 

J.W. Operating Co. 

O'Brien Energy Systems 

O'Brien Energy Systems 

Monterey Landfill Gas Corp./J.W. 

Oper. Co. 

City of Industry 

Waste Mgmt of North America 

GSF Energy 

Pacific Energy 

Monterey Regional Waste Mgmt 

GSF Energy 

Laidlaw Gas Recovery Systems 

Laidlaw Gas Recovery Systems 

Laidlaw Gas Recovery Systems 

Laidlaw Gas Recovery Systems 

Pacific Energy 

Monterey Landfill Gas Corp. 

LA County Sanitation Districts 

LA County Sanitation Districts 

Laidlaw Gas Recovery Systems 

8

 1 f,3 = 0.028 rr.3; 1 acre = 4046.9 m2; 1 ton = 907 kg 

NA = Not Applicable. ? = Not Available (Continued) # 

to 

cn 
23 

24 

25 

2 6 

2 7 

2 8 

2 9 

3 0 

31 

3 2 

3 3 

3 4 

35 

3 6 

3 7 

3 8 

3 9 

40 

41 

4 2 

43 

44 

Lsndfiaf Name 

Crazy Horse 

Canyon 

Otay Landfill («) 

Sycamore Canyon 

Newby Island 

Davis Street 

San Marcos 

Santa Clara 

Guadalupe 

Santa Cruz 

Austin Road 

Bradley 

Penrose (##) 

Sheldon-Arieta 

BKK 

Puente Hills- RIo 

Hondo (Mr*) 

Puente Hills-Gas 

Turbines (###) 

Puente HITIs-PERG 

(«*«) 

Yolo County 

Temple ton Gap 

County Line 

Synhltech 

New Mllford 

Location (City) 

Salinas 

San Diego 

San Diego 

San Jose 

SanLeandro 

San Marcos 

Santa Clara 

Santa Clara Co. 

Santa Cruz 

Stockton 

Sun Valley 

Sun Valley-LA 

Sun Valley-LA 

WestCovlna 

Whlttler 

Whlttler 

Whlttler 

Yolo County 

Colorado Springs 

Littleton 

Pueblo 

New Mllford 

TABLE 1. U.S. LANDFILL GAS ENERGY PROJECTS 

laocaItoo 

(SWB) 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CA 

CD 

GO 

0 0 

CT 

Use of Landfill gas 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen • Gas Turbine 

Electricity Gen - IC Engines 

Olrect Gas User - Med Btu 

Electricity Gen - Gas Turbine 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - Gas Turbine 

Electricity Gen - IC Engines 

Direct Gas User - Med Btu 

Electricity Gen - IC Engines 

Direct Gas User - Med Btu 

Electricity Gen - IC Engines 

Direct Use - Boiler & Cogen 

Engine 

Electricity Gen - Gas Turbine 

Electricity Gen - Steam Fed 

Turbine/Direct Use In Boiler 

Electricity Gen - IC Engines 

Pipeline Quality Gas 

Electricity Gen - IC Engines 

( 1 ) 

Upgrading Gas Into Diesel 

Fuel 

Electricity Gen - Gas Turbines 

d) 

Date Gas 

rtecnwry 

Began 

Dec-86 

Dec-86 

Dec-88 

Aug-84 

Jul-81 

Dec-88 

Dec-86 

Apr-84 

Nov-88 

Dec-85 

Jun-89 

Dec-85 

Jan-88 

8 6 

Mar-84 

Dec-83 

Nov-86 

Nov-89 

Jun-91 

Dec-86 

Jul-91 

Jun-91 

LFG 

Reeo/d 

(mfim) 

(scfd) 

0.8 

1.9 

1.2 

3.0 

1.9 

1.2 

0.9 

1.1 

0.6 

0.4 

3.0 

4.9 

0.8 

23.0 

0.5 

4.0 

33.0 

1.3 

2.4 

0.3 

2.0 

2.0 

Gross 

Energy 

Reco/d 

(MW) 

1.1 

3.4 

1.7 

5.0 

NA 

1.7 

1.1 

2.6 

0.9 

0.8 

NA 

10.0 

NA 

5.0 

0.55* 

4.0 

50.0 

1.5 

NA 

0.8 

NA 

3.3 

ToM 

landfill 

Asmage 

125 

525 

532 

342 

100 

95 

165 

115 

100 

171 

209 

72 

40 

500 

570 

570 

570 

700 

40 

90 

114 

90 

Devoted" 

Mel lane 

Recovery 

(•eras) 

125 

400 

100 

170 

100 

95 

125 

65 

30 

140 

209 

72 

40 

500 

570 

570 

570 

116 

33 

90 

114 

90 

Refuse 

Buried 

OnSrtfl 

(mi.T| 

1.8 

6.1 

4.5 

? 

9.7 

3.8 

3.5 

3.5 

4.5 

1.9 

13.4 

9.0 

3.0 

25.0 

60.0 

60.0 

60.0 

3.1 

2.0 

3.1 

3.5 

3.6 

USEPA, Thomeloe. 5/7/92 

LFG Developer/Operator 

Pacific Energy 

Pacific Energy 

Laidlaw Gas Recovery Systems 

Laidlaw Gas Recovery Systems 

G SF Energy 

Laidlaw Gas Recovery Systems 

Pacific Energy 

Laidlaw Gas Recovery Systems 

Laidlaw Gas Recovery Systems 

Pacific Energy 

Waste Mgmt of North America 

Pacific Energy 

Pacific Energy 

Douglas Energy 

LA County Sanitation Districts 

LA County Sanitation Districts 

LA County Sanitation Districts 

Monterey Landfill Gas Corp. 

Fuel Resources Development Co. 

Waste Mgmt of North America 

Fuel Resources Development Co. 

Waste Mgmt of North America * 

a 1 

t t A 

f.3 = 0.028 m3; 1 acre = 4046.9 m2; 1 ton = 907 kg 

kl- . »__i;.-.,KI „ "> 

(Continued) 

^i 
TABLE 1. U.S. LANDFILL GAS ENERGY PROJECTS USEPA. Thomeloe. 5/7/92 

<T> 

45 

46 

4 7 

4 8 

4 9 

50 

51 

52 

53 

54 

55 

56 

57 

58 

59 

60 

61 

Landfill Name 

Kenllworth Park 

Cherry Island 

Central Disposal 

(CDSL) 

Watts Rd Landfill 

Macon 

Kapaa 

Settler's Hill 

Blue Island 

CID 

Tazewell 

Milam 

Lake Landfill 

Pennington Ave 

Brown Station Rd 

Gude Southlawn 

Wayne Disposal 

Wood Street 

6 2 Rlverview 

Location (CHy) 

Washington 

Wilmington 

Pompano Beach 

Atlanta 

Macon 

Kaltua, Oahu 

Batavla 

Blue Island 

Chicago 

East Peoria 

Madison 

Northbrook 

Baltimore 

Prince George's 

County 

Rockvifle 

Bedevflle 

Lansing 

Rlverview 

Location 

(Stale) 

DC 

CE 

PL 

GA 

GA 

HI 

1 

IL 

IL 

IL 

IL 

1 

MD 

MO 

MD 

M 

M 

M 

Use of Landfill gas 

Direct Gas User- Med Btu 

Direct Gas User • Med Btu 

Electricity Gen - Gas Turbines 

( 5 ) 

Pipeline Quality Gas 

Direct User - Brick Kiln 

Electricity Gen • Gas Turbines 

Electricity Gen - Gas Turbines 

( 2 ) 

Direct Gas User - Med Btu 

Electricity Gen - Gas Turbines 

( 3 ) 

Electricity Gen - IC Engines 

( 2 ) 

Electricity Gen - IC Engines 

( 2 ) 

Electricity Gen - Gas Turbines 

(2) 

Direct Gas User • Med Btu 

Electricity Gen - IC Engines & 

Direct Use 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines & 

Direct Use 

Electricity Gen - IC Engines 

Electricity Gen - Gas Turbines 

Date Gas 

Rejcomwy 

Began 

Nov-82 

Oct-90 

May-89 

Apr-86 

Jan-85 

May-89 

Oct-88 

Nov-83 

May-89 

Jul-89 

Apr-91 

Jul-88 

Apr-84 

Jun-87 

Dec-85 

Jun-84 

Oct-85 

Dec-87 

tFG 

RecoVd 

(mitora) 

(scfd) 

0.3 

0.9 

10.0 

1.1 

1.1 

2.1 

2.5 

1.0 

6.0 

0.8 

0.9 

4.0 

0.9 

1.0 

1.4 

0.8 

0.7 

3.8 

Gross 

Energy 

RecoVd 

(MW) 

NA 

NA 

15. 0 

NA 

NA 

3.3 

3.9 

NA 

9.0 

1.6 

1.6 

6.0 

NA 

2.6 

2.5 

1.4 

? 

6.1 

Total 

landfifl 

Acreage 

145 

3 0 

210 

55 

120 

4 2 

179 

130 

173 

125 

110 

187 

6 0 

4 0 

9 1 

30 0 

2 0 0 

250 

UftQftN 

MvKtWW 

HeJCOKeJlry 

(acres) 

12 

17 

210 

55 

6 9 

4 2 

179 

130 

173 

110 

110 

187 

5 0 

20 

9 1 

30 0 

55 

145 

Refuse 

Buried 

OnSite 

(mi.T) 

2.7 

0.8 

15.3 

3.0 

3.5 

1.2 

7.7 

5.0 

20.0 

2.2 

4.3 

12.6 

2.0 

4.0 

4.8 

12.0 

1.6 

10.0 

LFG Dflvetoper/uperalor 

National Park Service 

Delaware Solid Waste Authority 

Waste Mgmt of North America 

Browning Ferris Industries 

Gas Resources Corp. 

Laidlaw Gas Recovery Systems 

Waste Mgmt of North America 

GSF Energy 

Waste Mgmt of North America 

Waste Mgmt of North America 

Waste Mgmt of North America 

Waste Mgmt of North America 

Maryland Recycling & Rehandllng 

The Magutre Group Inc. 

Pacific Energy 

Wayne Energy Recovery. Inc. 

Granger Renewable Resources. Inc. 

Rlverview Energy Systems. Inc. 

e 1 ft.3 = 0.028 m3; 1 acre = 4046.9 m2; 1 ton = 907 kg 

NA = Not Applicable. ? = Not Available (Continued) 

f 

oo 
63 

64 

65 

66 

67 

68 

69 

70 

71 

72 

73 

74 

75 

76 

77 

78 

79 

80 

81 

82 

83 

Landfill Name 

Grand Ledge 

Woodland Meadows 

Anoka 

North Sanitary 

Little Dixie 

Rowland 

Wllder's Grove 

Manchester 

Turnkey 

Kinsley 

Edison 

Hackensack 

Meadowlands 

H.S.L. 

L & D 

High Acres 

Mohawk Valley 

Orange County 

Blydenburg Road 

East Northport 

Al Turi 

Hempstead 

Location (City) 

Watertown 

Wayne 

Anoka 

Maryland Hts 

Jackson 

Raleigh 

Raleigh 

Manchester 

Rochester 

Deprford 

Township 

Edison 

Kearny 

Lafayette 

Mount Hotly 

Falrport 

Frankfort 

Goshen 

Haurjpauge 

Huntington 

Mlddletown 

Oceanslde 

TABLE 1. U.S. LANDFILL GAS ENERGY PROJECTS 

leaflon 

(Site) 

M 

M) 

MN 

MD 

MS 

NC 

NO 

NH 

NH 

NJ 

NJ 

NJ 

NJ 

NJ 

NY 

NV 

NY 

NY 

NV 

NT* 

NY 

Use of Landfill gas 

Electricity Gen - IC Engines 

Direct Gas User - Boilers 

Direct Ga s User - Med Btu 

Direct Ga s User - Med Btu 

Direct Ga s User • Med Btu 

Electricity Gen - IC EnginesDirect Gas User (Boiler Fuel) -

Med Btu 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Pipeline Quality Gas 

Electricity Gen - IC Engines 

Electricity Gen - Gas Turbines 

( 2 ) 

Electricity Gen • IC Engines 

( 2 ) 

Electricity Gen • IC Engines 

Electricity Gen - Gas Turbines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Date Gas 

RGCWwy 

Began 

Apr-91 

Jan-91 

Nov-89 

Jun-81 

Sep-90 

Jun-84 

Dec-89 

Jul-88 

Feb-92 

Jun-85 

Sep-90 

Dec-89 

Aug-90 

Mar-90 

Apr-91 

Oct-91 

Dec-88 

Dec-88 

Apr-84 

Jun-87 

Dec-90 

IFG 

ReceVd 

(mmm) 

(sdd) 

1.2 

2.1 

0.8 

0.3 

1.6 

0.0 

1.5 

0.5 

1.3 

1.3 

3.0 

7.2 

0.7 

2.5 

0.5 

0.4 

2.1 

2.3 

0.8 

2.5 

2.9 

Gross 

Energy 

ReeoVd 

(MW) 

2.4 

NA 

NA 

NA 

NA 

0.1 

NA 

0.8 

2.4 

2.4 

4.4 

NA 

1.0 

3.9 

1.6 

0.8 

3.3 

4.0 

1.2 

4.1 

4.0 

Total 

landfill 

Acreage 

200 

203 

100 

50 

30 

25 

125 

30 

96 

136 

30 

350 

30 

175 

9 2 

80 

70 

70 

44 

72 

180 

Devoted 

Metrane 

Recovery 

(seres) 

60 

175 

100 

30 

30 

4 

90 

30 

SO 

70 

30 

300 

30 

175 

92 

50 

70 

40 

37 

72 

110 

Refuse 

Buried 

OnSite 

(«*T) 

f 

7.0 

3.8 

? 

1.8 

0.1 

3.5 

1.2 

3.1 

6.0 

2.5 

30.0 

1.5 

3.3 

3.4 

1.7 

4.0 

2.0 

USEPA. Thomeloe. 5/7/92 

LFG Developer/Operator 

Granger Renewable Resources. Inc. 

Waste Mgmt of North America 

Waste Mgmt of North America 

Fred Weber Company 

Browning Ferris Industries 

Natural Power 

Natural Power 

Energy Tactics 

Waste Mgmt of North America 

United Environmental Services, Inc. 

O'Brien Energy Systems 

G SF Energy 

O'Brien Energy Systems 

Waste Mgmt of North America 

Waste Mgmt of North America 

Waste Mgmt of North America 

Laidlaw Gas Recovery Systems 

JWP. Inc. 

. _ H. O. Pern Machinery. Inc. 

, g I J.W. Operating Co. 

_ 5 1 Energy Tactics # 

a 1 ft' = 0.028 m3; 1 acre = 4046.9 m2; 1 ton = 907 kg 

NA = Not Applicable, ? = Not Available 

(Continued) 

CO 
84 

85 

86 

87 

88 

89 

9 0 

91 

92 

93 

94 

9 5 

96 

9 7 

98 

9 9 

100 

101 

102 

103 

104 

105 

Landffl Name 

Oyster Bay 

Rtverhead 

Monroe Livingston 

Smlthtown 

Fresh Kills 

Onondaga County 

Horse Block Road 

Elda Landfill 

Rumpke 

Short Mountain 

F. R. & S. 

East Permsboro 

Mazzaro 

GROWS 

Greater Lebanon 

Pottstown 

Consho-hocken 

Taylor 

Central 

Chestnut Ridge 

McCarty Road 

DFW 

tocafton (CHy) 

Oyster Bay 

Rtverhead 

Scottsvllle 

Smlthtown 

Staten Island 

Syracuse 

Yaphank 

Cincinnati 

Coleraln 

Lane County 

Blrdsboro 

Enola 

Flnley Township 

Morrlsville 

N. Lebanon 

Township 

Pottstown 

Swodoland 

Taylor 

Johnston 

Herskefi 

Houston 

Lewlsvllle 

TABLE 1. U.S. LANDFILL GAS ENERGY PROJECTS 

uxa-

(Sate) 

NY 

Nr* 

NY 

NY 

NY 

W 

NY 

OH 

OH 

CR 

PA 

PA 

PA 

PA 

PA 

PA 

PA 

PA 

Fl 

TN 

TX 

TX 

Use of Landfill gas 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

(4 ) 

Electricity Gen - IC Engines 

Pipeline Quality Gas 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Direct Gas User • Boilers 

Pipeline Quality Gas 

Electricity Gen • IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - Gas Turbines 

(2) 

Electricity Gen - IC Engines 

Electricity Gen - Gas Turbines 

(2 ) 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

(3) 

Pipeline Quality Gas 

Electricity Gen - Gas Turbine 

(1 ) 

Date Gas 

Recovery 

Began 

Dec-85 

Jan-85 

Dec-88 

Jan-85 

Aug-82 

Dec-87 

Jan-84 

Apr-88 

Sep-86 

Jan-92 

Jul-87 

Sep-85 

May-89 

Dec-87 

Nov-85 

Apr-89 

Mar-86 

May-88 

Nov-89 

Jan-92 

Feb-87 

May-88 

LFG 

Reco/d 

(mtionj) 

(Sdd) 

1.4 

0.4 

1.7 

0.7 

9.5 

0.7 

1.9 

2.6 

5.4 

0.9 

0.5 

0.1 

2.0 

4.0 

0.9 

4.0 

2.0 

0.7 

6.9 

1.0 

8.0 

2.0 

Gross 

Energy 

Reco/d 

(MW) 

2.6 

0.6 

3.2 

1.0 

NA 

1.0 

2.8 

NA 

NA 

1.6 

0.8 

0.1 

2.4 

6.0 

1.2 

6.0 

2.8 

2.0 

12. 3 

2.4 

NA 

3.0 

Total 

landfin 

Acreage 

120 

40 

9 0 

30 

3.000 

60 

100 

106 

200 

275 

25 

20 

90 

434 

75 

178 

25 

45 

150 

108 

270 

416 

Devoted 

UsttW 

RtKomfy 

(acres) 

6 0 

4 0 

9 0 

20 

400 

6 0 

6 0 

106 

150 

50 

25 

14 

30 

100 

4 0 

90 

25 

40 

100 

75 

270 

120 

Refuse 

Buried 

OnSite 

(tni.T) 

2.8 

3.0 

2.9 

1.4 

28.0 

1.3 

6.8 

5.8 

14.0 

2.6 

1.6 

0.4 

3.0 

11.6 

1.0 

9.9 

3.6 

2.0 

11.3 

2.8 

14.0 

7.3 

USEPA. Thomeloe, 5/7/92 

LFG Develooe7rOpei<daR 

Energy Tactics 

United Environmental Services. Inc. 

Waste Mgmt of North America 

Energy Tactics 

G SF Energy 

Energy Tactics 

H. O. Penn Machinery. Inc. 

Waste Mgmt of North America 

G SF Energy 

Emerald People's Utility District 

O'Brien Energy Systems 

East Permsboro Township 

O'Brien Energy Systems 

Waste Mgmt of North America 

Lebanon Methane Recovery, Inc. 

Waste Mgmt ot North America 

O'Brien Energy Systems 

O'Brien Energy Systems 

Palmer Capital 

Waste Mgmt of North America 

G SF Energy

 ! 

Waste Mgmt ot North America 

a 1 f.3 = 0.028 rr.3; 1 acre - 4046.9 m?; 

NA = Not Applicable. ? = Not Available 

1 ton = 907 kg 

(Continued) * 

Tl 
I O 

106 

107 

108 

109 

110 

111 

112 

113 

114 

* 

• • 

« 

ft* 

«#« 

Landfill Name 

Lorton (I-95) 

Mount Trashmore 

Brattleboro 

Pheasant Run 

Metro 

Omega Hills 

Winnebago 

Appleton 

Land Reclamation 

Location (City) 

Fairfax County 

Virginia Beach 

Brattleboro 

Bristol 

Franklin 

Menomonee 

Falls 

Oshkosh 

Outagamie 

County 

Radne 

Supplemented with natural gas. 

TABLE 1. U.S. LANDFILL GAS ENERGY PROJECTS 

Location 

(Sta») 

VA 

VA 

VT 

Wi 

Wl 

WI 

Wi 

Wi 

Wl 

Use ol Landfill gas 

Electricity Gen - IC Engines 

Electricity Gen - Gas Turbines 

Electricity Gen - IC Engines 

Electricity Gen - IC Engines 

(2) 

Electricity Gen - Gas Turbines 

(2) 

Electricity Gen - Gas Turbines 

(3) 

Electricity Gen - Gas Turbines 

Electricity Gen - IC Engines & 

Direct Use 

Direct Gas User - Med Btu 

Date Gas 

Recovery 

Began 

Nov-91 

Apr-90 

Aug-82 

Feb-92 

Jan-86 

Dec-85 

Jun-90 

May-91 

87 

tFG 

Reco/d 

(mfltara) 

(scfd) 

2.0 

Temp. 

Shutdown 

0.4 

0.8 

3.0 

4.0 

2.0 

1.4 

1.2 

Gross 

Energy 

Reco/d 

(MW) 

3.0 

9.0 

0.7 

1.6 

6.0 

9.0 

3.2 

2.5 

NA 

Total 

landfill 

Acreage 

290 

350 

3 0 

80 

108 

83 

111 

460 

61 

Ovtoted 

Merrane 

Recovery 

(aova) 

25 

70 

15 

80 

108 

83 

105 

77 

45 

Refuse 

Buried 

OnSite 

<m*n 

17.5 

7.0 

0.6 

2.1 

8.3 

8.2 

5.0 

3.0 

? 

USEPA, Thomeloe, 5/7/92 

LFG uowjlopor/Operator 

Ml Co-Gen 

City of Virginia Beach 

Vermont Energy Recovery. Inc. 

Waste Mgmt of North America 

Waste Mgmt of North America 

Waste Mgmt of North America 

Winnebago County 

Outagamie County 

Land Reclamation Co. 

Includes 1850 kW project expansion In 1991: receives gas from Ventura Coastal LF estimated at 28 hectares (70 acres) and 2.3 million tonnes of 

refuse (2/3 gas Ventura Coastal. 1/3 Santa Clara). 

Includes 1850 kW project expansion In 1991. 

Receives gas from 3 landfills - Penrose, Sheldon-Arieta. and Bradley. 

This landfill has 3 separate energy recovery projects. 

" 1 ft3 a 0.028 nv»; 1 acre = 4046.9 m*; 1 ton = 907 kg 

NA = Nol Applicable, ? = Not Available 

I 

(Continued) 
P.42 

IC Engines 

c o 

"5 

3 Med Heating-Value Gas 5 

•S 

Turbines 

SL High Healing-Value Gas 

1 0 20 30 40 50 

Number of LFG Projects 

60 70 

Figure 1. Number of U.S. Landfill Gas Projects by Energy Utilization Option 

0 10 15 20 25 

Number of LFG Projects 

30 35 40 

Figure 2. Number of U.S. Landfill Gas Projects by State 

for those States with Three or More Projects 

10 
P.43 

is located. Engines are typically used at sites where gas quantity is capable of producing 1 

to 3 MWe. Turbines are typically used at sites producing more than 3 MWe. 

Reciprocating IC engines drive electrical generators to produce electrical power 

which is typically sold to the local electric utility. Engines used in this application are sold 

by three manufacturers - Caterpillar, Cooper-Superior, and Waukesha. Each of the 3 

manufacturers has in place more than 20 engines at U.S. landfill sites (GRCDA, 1989). 

These manufacturers design engines that are specific to LFG applications (i.e., corrosion 

resistant). Typically, warranties that guarantee engine performance require the operator to 

agree to certain conditions regarding engine operation and maintenance. 

Reciprocating engines used for LFG applications may be stoichiometric 

combustion or lean combustion engines. The "lean-burn" engines are turbocharged and 

bum fuel with excess air. The stoichiometrically carbureted or "naturally aspirated" 

engines have air in the fuel/air mix just sufficient to bum the fuel. The case studies provide 

four examples-three LFG projects using lean-bum engines and one LFG project using 

naturally aspirated engines. 

The lean-bum engines are typically used where NO, and CO emissions are of 

concern. Stoichiometric combustion can result in relatively high NO, emissions which can 

vary widely due to carburetor setting and other variables. Waukesha suggested that 2.2 to 

6.7 Ltg/J (6 to 18 g/hp-hr) is a typical range of NO, emission from stoichiometric engines 

(Stachowicz, 1989). Lean-bum engines are available that minimize (1) the production of 

NO, and (2) fuel consumption. At landfill sites with gas flows below -5,700 scmd 

(-200,000 scfd), an operator could use one or two naturally aspirated engines. The NO, 

emissions would be less than 230 tonnes/yr (250 tons/yr), and the source would not be 

subject to new source review. At sites over -5,700 scmd (-200,000 scfd), lean-bum 

engines are used to avoid new source review. The destruction performance of a lean-bum 

engine manufactured by Caterpillar (i.e., the Caterpillar 3516 SI Engine) at various NO, 

emissions levels reported by the manufacturer is (Chadwick, 1989): 

NO, (Hfi/J) NOT (g/hp-hr) NMQCPestruction Efficiency (%) 

0.7 2.0 98.3 

1.9 5.0 98.7 

3.7 10.0 99.1 

Note that there is a trade-off between low NO, emissions and the reduction of NMOCs. 

Data from 15 IC engines fueled with LFG were collected by the EPA. The range 

(at 15% O2) of NO, was 50 to 225 ppmvd (0.6 to 3.3 g/hp-hr). The range (at 15% O2) of 

CO is 43 to 550 ppmvd (0.6 to 7.2 g/hp-hr). Emissions of S0 2 were measured for only 

one IC engine: the concentration of S0 2 (at 15% O2) was 1.5 ppmvd (Thomeloe and 

Evans, 1989; EPA, 3/91). 

Gas-fed turbines are also used at landfills to generate electricity. Gas turbines take 

large amounts of air from the atmosphere, compress it, bum fuel to heat it, then expand it 

in the power turbine to develop shaft horsepower. This horsepower can be used to drive 

pumps, compressors, or electrical generators (McGee and Esbeck, 1988). Gas turbines are 

used at 21 U.S. landfills to produce 108 MWe of power. Waste Management of North 

America, Inc. has found that gas-fed turbines typically have parasitic energy losses of 17% 

of gross output as compared to 7% for IC engines. A factor to consider is that turndown 

performance is poor in comparison to IC engines. Turbines perform best when operated 

at full load, and difficulties can occur when operated at less than full load. In addition, 

trace constituents have been reported to cause corrosion, combustion chamber melting, 

and deposits on blades. However, these difficulties can be overcome as demonstrated by 
P.44 

*_*..-

Waste Management of North America (Schlotthauer, 1991). A major advantage reported 

by sites using gas turbines is that generally less day-to-day maintenance is required as 

compared to the lean-bum engines. 

Emissions of NO, for seven gas turbines fueled with LFG ranged from 11 to 174 

ppmvd at 15% 02. Emissions of CO ranged from 15 to 1,300 ppmvd at 15% 02 , and 

emissions of S02 ranged from 2 to 18 ppmvd at 15% 02 (Thomeloe and Evans, 1989; 

EPA, 3/91). Emissions of S02 are not expected to be significant since landfill gas 

typically contains relatively low amounts of sulfur compounds as compared to fossil fuels. 

The new source performance standard for gas turbines with a power output of 2.93 to 

29.3 MWeis 150 ppmvd of NO, at 15% 02 (EPA, 1977). Although the units tested were 

below this cutoff, six of the seven turbines did have less than 150 ppmvd of NO, at 15% 

02 . Data for four gas turbine facilities were presented by Waste Management at the Air 

and Waste Management Association's 82nd Annual Meeting in June 1989 (Maxwell, 

1989). The data for NO, emissions from the Solar Centaur T-4500 LFG turbine ranged 

from 22 to 37 ppmv at 15% 02 . with a median of 30 ppmv. 

Steam-fed turbines are in use at three sites to produce 64 MW, of power. The 

largest landfill-gas-to-energy plant is the Puente Hills Energy Recovery from Gas facility 

(PERG), located at the Puente Hills Landfill in Whittier, California. This site began 

recovering LFG for energy utilization in November 1986. It is operated by the Los 

Angeles County Sanitation Districts. The facility consists of twin Zum Industries, Inc. gasfired steam generators. Each of the units fires 420,000 scmd (10.300 scfm) of LFG, 

producing 95,340 kg (210,000 lb) of steam per hour at 9.3 MPa (1350 psig). heated to 

540°C (1000°F). This steam drives a Fuji Electric Co. Ltd. turbine that generates 

approximately 50 MWe net, that is sold to Southern California Edison (Valenti, 1992). 

High-Heating Value Gas. Seven sites in the U.S. upgrade LFG to pipeline quality. 

This option was considered more attractive in the early 1980s when the price of oil and 

natural gas helped make this more economical. The sites that are producing pipeline 

quality gas were initiated in the early 1980s when gas prices on a heating-value basis were 

comparable with oil. These sites have an average LFG flow rate of 142,000 scmd 

(5 million scfd) with the lowest gas flow rate being 31,150 scmd (1.1 million scfd) and 

the highest being 269,000 scmd (9.5 million scfd). Stringent cleanup technology is 

applied to purify the gas to pipeline quality by removing the trace constituents and C02. 

Similar to the medium-heating value applications, a nearby natural gas pipeline is needed. 

The largest operator of facilities producing pipeline quality gas from LFG is Air Products 

and Chemicals, Inc. Low natural gas prices in the late 1980s forced several previous 

projects to shut down, and continue to inhibit the development of new high-heating value 

projects in the U.S. However, sites in the Netherlands are finding more favorable 

economics (Scheepers, 1991). 

A site that began operation last year in Pueblo, Colorado, is producing liquid 

diesel fuel from LFG. This site is operated by Fuel Resources Development, Inc. and 

began producing commercial product in January. A second site in the U.S. may be used 

to produce vehicular fuel from LFG. The South Coast Air Quality Management District 

has awarded a contract to demonstrate a process for producing methanol from LFG. The 

site selected for this demonstration is the BKK landfill, where there was co-disposal of 

hazardous and municipal waste. TeraMeth Industries is responsible for the demonstration 

and research is being coordinated with the EPA. The demonstration is anticipated to 

begin in 1993. 

Other Options for Landfill Gas. Fuel cells are a potentially attractive option for 

LFG because of higher energy efficiency, availability to smaller as well as larger landfills, 

and recognition for minimal byproduct emissions. Other advantages include minimal 

labor and maintenance, and (because there are no moving parts) the noise impact is 

minimal. Hydrogen from the landfill gas is combined electrochemically with oxygen 

12 
P.45 

from the air to produce dc electricity and by-product water. The fuel cell is designed for 

automatic, unattended operation, and can be remotely monitored. The EPA's Air and 

Energy Engineering Research Laboratory initiated a project in 1991 to demonstrate the 

use of fuel cells for LFG application. The type of fuel cell being demonstrated is a 

commercially available 200 kWe phosphoric acid fuel cell power plant. The 1-year fullscale demonstration is scheduled for 1993. 

The major issue associated with this demonstration is designing a LFG cleanup 

process that will remove the trace constituents from the LFG and at the same time not be 

cost prohibitive. Since the composition of LFG varies over time, designing a process that 

can allow for this variability is difficult. A cleanup process has been proposed and is to be 

evaluated later this year. The fuel pretreatment system incorporates two stages of 

refrigeration combined with three regenerable adsorbent steps (Sandelli, 1992). It is 

hoped that, if the EPA demonstration of the use of fuel cells is successful, more landfill 

owner/operators will consider fuel cells as an option for LFG utilization. Given the higher 

energy efficiency and potential for minimal byproduct emissions, fuel cells may be the 

most attractive option for areas where there are stringent requirements for NO, and CO 

emissions. 

Economic*; 

A major factor in helping to encourage LFG energy projects is the Public Utility 

Regulatory Policy Act (PURPA). It guarantees that utilities purchase power that was 

generated from landfills at a price related to the costs that utility would experience to 

produce the same amount of power. Although this guarantees a purchaser for the power, 

the power sale revenues may be low if the utilities' own generating costs are low. In 

addition, tax credits have been available that also help to encourage renewable energy 

projects, such as LFG utilization. 

The major capital costs of a LFG energy recovery project are identified in Table 2 

as estimated in a recent paper by George Jansen of Laidlaw Technologies, Inc. Laidlaw's 

experience suggests that LFG projects need to be over 1 MW, and have an electrical price 

of at least $0.06-0.07/kWh including any capacity payments. Royalties should not exceed 

12.5% at this energy pricing (Jansen, 1992). Laidlaw suggests that, if higher royalties are 

offered, the percentage should be a function of energy pricing over and above the base 

energy rate as inflation occurs. A range in the variability of the cost for each major 

component is also provided in Table 2. 

The major cost and revenue components include (1) administration and 

development costs, (2) capital costs, (3) operating and maintenance costs, 

(4) royalty payments, (5) tax credits, and (6) energy-related revenues. A brief description 

is provided of each of these components. 

• Administrative costs include legal fees, permit applications, and contract 

negotiations including gas lease agreements and power purchase agreements. 

These costs may vary widely depending upon the environmental issues, 

development considerations, and regulatory requirements. 

• Capita] costs include the cost of gas extraction and cleanup, energy conversion 

equipment, building, flares, and site modifications for construction. 

• Operating and maintenance costs include the costs associated with the 

operation and maintenance of the energy project, labor, utilities, taxes, and 

insurance. 

13 
P.46 

• __.-

TABLE 2. CAPITAL COST ESTIMATE 

Estimate of Capital Costs for a 1 MW, Landfill Gas Energy Utilization Project 

Item 

Collection Systems 

Fees-Planning/Environment/LegaP 

Interconnect Cost 

Generating Equipment 

Contingency 

Total 

Cost' 

CX1Q3) 

200 

30 

76 

970 

225 

1500 

Percent1 

13 

2 

5 

65 

11 

100 

Range of 

Value 

($103/kWh^ 

200-1000 

30-1000 

20-500 

500-2000 

— 

850-4500 

'These costs were provided by Laidlaw Technologies, Inc. (Jansen, 1992) 

2The range in cost of gas cleanup systems is $10,000-$500,000 ($103/kWh) 

3Legal fees are approximately 50% of the total (i.e.. -$15.000-$500,000) 

• Royalty payments are proportional to energy output (or net or gross revenue) 

and are defined by the contract. Royalties are negotiated and may be paid to 

the landfill owner, owner of the gas extraction or delivery rights, or initial 

project developer. Royalties can range from 5 to 20% of gross energy sales. 

• Tax credits are benefits proportional to gas energy delivery which were 

legislated by Congress (Section 20 of the IRS Code). These credits are a direct 

offset to taxes and can only be used to offset a profit. The tax credits will 

extend through the year 2002 and are allowable for extraction systems 

installed prior to the end of the year 1992. However, the most recent version 

of the tax bill being considered by Congress does not include a tax credit for 

non-fossil fuel projects. 

• Revenues for energy sales are usually based on prices of the "competition" of 

equivalent energy sources (i.e., petroleum products). Since the value of the 

energy base commodity can fluctuate, this can impact profit. The early LFG 

projects were based on an established firm price for net energy which provided 

a substantia] degree of security to developers. 

Case Studies 

The EPA's Air and Energy Engineering Research Laboratory initiated a project in 

1991 to document the options for LFG utilization. This work included gathering data on 

the operating and maintenance requirements, the financing and contractual arrangements, 

14 
P.47 

and "lessons learned" from the six sites included in the case studies. This paper provides 

a brief summary of the case studies with emphasis on identifying the different utilization 

options in use. The final report will contain more detailed infonnation for these sites 

including capital and operating costs, process flow diagrams, and data regarding the 

environmental benefits of LFG utilization. 

Sites were selected to provide insight on the kinds of issues associated with LFG 

utilization and actions taken by operators and equipment manufacturers to ensure 

successful projects. Many companies have been successful in finding innovative solutions 

to difficulties arising from LFG utilization. Several firms have found that gas cleanup is 

critical to the performance of both engines and turbines. The design of the gas cleanup 

must be specific to the composition of the gas being recovered and allow for the 

variability which occurs over time. The EPA has initiated a follow-up project which will 

focus on the issues of gas cleanup, equipment design, and operational modifications. The 

focus of this initial project is to identify the different approaches for LFG utilization using 

six case studies to illustrate the different options. Provided below is a brief summary of 

the information gathered at the six LFG energy projects. 

Site 1. Brown Station Landfill. Prince George's County. Maryland. LFG is used 

to supply both the electrical and heating needs of a county building in addition to 

producing electricity for sale to the local utility. The energy equipment includes a gas 

cleanup and pumping station, a 3,230 m (2-mile) pipeline transmission system, three 

engine generators, and a boiler which supports the heating and hot water system of the 

21,800 m2 (235,000 sq ft) county correctional facility. The three engines are lean-bum 

turbocharged. Approximately 28,320 scmd (1 million scfd) of gas is recovered from 3.6 

million tonnes (4 million tons) of landfilled waste. This site began operation in June 1987 

and produces about 2.6 MW, of power. 

This site experienced atypical difficulties during start-up, resulting in one of the 

three engines seizing after less than 500 hours of operation. Modifications have been 

made to the engine to make it "corrosive resistant" including hardened valve guides, 

chrome valve stems, modified piston rings, and elevated coolant temperatures. Operations 

were also modified including more frequent oil checks and changes. Since this 

occurrence, the site has had successful operation. Speculation about what contributed to 

the engine seizing suggests that higher levels of chlorinated organics (than is typical for 

landfills) may have caused the corrosion. Inspection of the engine snowed evidence of 

extensive corrosion including deposit buildups which reduced piston clearances. 

Site 2. Central Landfill. Yolo County. California. Gas from this landfill is used to 

fuel three IC engines to generate 1.5 MW,. The generated power is delivered via an 

interconnect 1,200 m (0.75 mile) to nearby PG&E high voltage power lines. Yolo 

County, the owner of the landfill, receives royalties based on net power and capacity sales. 

This energy recovery project began operation in November 1989. Approximately 36,800 

scmd (1.3 million scfd) of LFG is recovered from 2.8 million tonnes (3.1 million tons) of 

refuse. This project has experienced a number of difficulties including equipment 

problems. The types of engines were of an earlier design lacking newer adaptations to 

lean-bum operation on LFG. Modifications to the engines are being considered to make 

them more corrosive resistant for LFG applications. Because of the difficulties 

experienced at this site, the revenue from the royalties has dropped. 

Site 3. Otav Landfill. San Diego County. California. This site is recovering 

53,800 scmd (1.9 million scfd) of LFG to generate 3.4 MW, using a lean-bum 

engine/generator set. The electricity is sold to the local utility. The Otay landfill contains 

approximately 5 million tonnes (-6.1 million tons) of refuse. The energy recovery 

project began operating in December 1986. The facility exports a net output of about 

3400 kW at an average sale price of -$0.09 kWh, and typically obtains more than $2 

ic ; 
P.48 

million per year in gross power sale revenue. The LFG energy recovery project is 

operated by Pacific Energy who are responsible for the operation of 10 LFG energy 

projects, nine in California and one in Maryland. 

Site 4. Monterey Landfill. Marina. California. This site produces 1.2 MW, from 

23.300 scmd (0.9 million scfd) of LFG. This project is one of the first in the U.S., 

beginning operation in December 1983. The installation is the result of persistence by 

participants who were aware of the potential benefits of energy recovery from LFG. 

Approximately 3.4 million tonnes (3.7 million tons) of refuse is buried at this site as of 

1992. The Monterey Regional Waste Management District owns and operates the engines, 

receiving the profit from engine operation. This site uses naturally aspirated engines and 

catalysts for the outlet exhaust to reduce NO, and CO. This site has demonstrated exhaust 

catalyst use and has found that the oil type and alkalinity are critical to the engines' 

performance. Technical success is good despite that gas cleanup is less stringent than is 

typical for other sites. This site can be considered one of the pioneers in energy recovery 

from LFG. 

Site 5. Sycamore Canvon Landfill. San Diego. California. This site is producing 

1.7 MW, from 34,000 scmd (1.2 million scfd) of LFG. This project began operating in 

December 1988 using two gas-fed turbines fueled with LFG to generate electricity which 

is sold to the San Diego Gas and Electric grid. This energy project was owned by Solar 

prior to being sold to Laidlaw Technologies, Inc. Solar reported that efficiency is reduced 

by 13% from the efficiency that would be obtained with the same turbine on more 

conventional pipeline gas or distillate fuels, due to the greater parasitic compression load. 

The equipment is occasionally limited due to inadequate quantities of LFG. This 

difficulty has occurred at other sites and gas projections for newer projects tend to be 

more conservative. 

Site 6. Wilder's Grove Landfill. Raleigh. North Carolina. This site is an excellent 

example of how LFG can be used directly by an industrial client as medium-heating value 

fuel. The gas from the Raleigh landfill is piped 1,600 meters (1 mile to a pharmaceutical 

facility for use as boiler fuel to produce 11,000 kg (24,000 lb) of steam per hour. This 

project began operating in December 1989 and is expanding. A second boiler is being 

added this year. Approximately 42,500 scmd (1.5 million scfd) of gas is recovered from 

approximately 3.2 million tonnes (3.5 million tons) of refuse. Natural Power initiated this 

project and is responsible for its operation. 

Natural Power pays royalties to the City of Raleigh based on a percentage of steam 

sales. This project also receives tax credits on the extracted gas. All participants in this 

project appear satisfied with the performance of this project to date. However, Natural 

Power, who was the prime motivator in getting this project initiated, provided many years 

of work on the project during which there was no financial return. 

This site was prone to off-site gas migration prior to the installation of the gas 

collection and recovery project. Since the installation of the energy project, gas migration 

off-site has not been detected. In addition, other environmental benefits are realized 

including the reduction from emissions of NMOCs, toxics, and methane, which is a 

contributor to global climate change. 

Natural Power, the developer for this project, is presently negotiating a contract 

with a landfill in Kiev, in the Ukraine. This site has over 9 million tonnes (10 million tons) 

of waste. The gas is to be used to generate electricity for the Ukrainian capital. 

16 
P.49 

CONCLUSIONS 

The utilization of LFG is sensible in terms of economics, the environment, and 

energy usage. The utilization of altemative energy sources such as LFG extends our 

global fossil fuel resources. Not only are emissions directly reduced when LFG is 

collected and recovered for utilization, but emissions are also indirectly reduced when 

secondary air/emission impacts associated with fossil fuel use are considered. U.S. 

landfills are currently recovering -1.2 million tonnes of methane and producing 344 MWe 

of power. The proposed Clean Air Act regulations for MSW landfill air emissions are 

expected to result in additional emission reductions ranging from 5 to 7 million tonnes of 

methane. Hopefully, utilization of LFG will be considered and encouraged for those sites 

affected by the proposed Clean Air Act regulations. This would result in increased 

benefits to our economy, energy resources, and global environment. 

REFERENCES 

1. Berenyi, Eileen, and Robert Gould, 1991-92 Methane Recovery from Landfill 

Yearbook, Governmental Advisory Associates, 1991. 

2 . Chadwick, Curt. Market Development Department, Caterpillar Inc., Letter to Susan 

Wyatt, EPA/OAQPS. February 21, 1989. Response to request for information on 

IC engines used to bum LFG. 

3. Federal Register. Vol 56. No. 104. May 30, 1991, pp. 24468 - 24528. 

4. GRCDA/SW.ANA, "Engine and Turbine Panel Presentations." Proceedings from 

the GRCDA 9th International Landfill Gas Symposium, 1989. 

5. Jansen. G.R. "The Economics of LFG Projects in the United States." Presented 

at the Symposium on LFG/Applications and Opportunities in Melbourne, 

Australia, February 27, 1992. 

6. Khalil, M.A.K., and R.A. Rasmussen. "Constraints on the Global Sources of 

Methane and an Analysis of Recent Budgets." Tellus, 42B, 229-236, 1990. 

7. Maxwell, Greg. "Reduced NO, Emissions from Waste Management's LFG Solar 

Centaur Turbines." Proceedings of Air & Waste Management Association's 82nd 

Annual Meeting in Anaheim, California, June 1989. 

8. McGee, R.W. and D.W. Esbeck. "Development, Application, and Experience of 

Industrial Gas Turbine Systems for LFG to Energy Projects." Published in the 

Proceedings of GRCDA's 11th Annual International LFG Symposium. March 

1988. 

9. Sandelli, G.J. "Demonstration of Fuel Cells to Recover Energy from LFG." EPA600-R-92-007 (NTIS PB92-137520), January 1992. 

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Proceedings of the Third International Landfill Symposium, Sardinia, October 

1991. 

11. Schlotthauer, M. "Gas Conditioning Key to Success in Turbine Combustion 

Systems Using Landfill Gas Fuels." GRCDA/SWANA's 14th Annual Landfill Gas 

17 
P.50 

Symposium in San Diego, California. Published in the Symposium Proceedings. 

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1977. 

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-x ' . # 

(• 

• __.-

18 
P.51 

atNi UY-IUF resources inc. . a-.d-sd .I^-*IPIVI . /uooaioo-ta-' isi»^i"«.n t i 

* "' '- ATTACHMENT 2 

DRAFT 

Impact Assessment of Advanced Equipment 

for the Building Sector 

Electric Utility Impact Methodology 

Final Report 

Prepared for: 

U.S. Department of Energy 

Building Equipment Division 

Office of Building Energy Research 

Office of Building Technologies 

Prepared by: 

ICF Resources Incorporated 

Under Subcontract to 

Arthur D. Little 

August 19, 1993 

ftfr'wasaiMswtsBsssgBSaVaCTrtg'^^ i , , _. 
P.52 

EPA -- Marginal En 

09/09/93 

(Ibs.AWh) 

LA 

ECAR 

Florida 

MAAC 

MAIN 

WSCC-N 

NPCC 

SPP 

SERC 

ERCOt 

HAPP 

WSCC-S 

1995 

GWH* 

247992 

532625 

167680 

248605 

236456 

258349 

268190 

286727 

566404 

241999 

148095 

121918 

ssion Factors: 

1995 

C02 

1.177 

1.939 

1.139 

1.463 

1.981 

1.135 

1.207 

1.486 

1.779 

1.206 

1.714 

1.703 

1995 

S02 

0.000 

0.006 

0.000 

0.005 

0.008 

0.000 

0.000 

0.001 

0.003 

0.000 

0.002 

0.001 

1995 

NOX 

0.004 

0.007 

0.003 

0.005 

0.007 

0.004 

0.004 

0.005 

0.006 

0.004 

0.006 

0.006 

2005 

GWH* 

290079 

592182 

216896 

294818 

269174 

283306 

298198 

350135 

705252 

312385 

167978 

157912 

2005 

C02 

1.142 

1.349 

1.124 

1.202 

1.424 

1.154 

1.255 

1.379 

1.214 

1.193 

1.469 

1.081 

2005 

S02 

0.000 

0.001 

0.000 

0.000 

0.002 

0.000 

0.000 

0.001 

0.000 

0.000 

0.001 

0.000 

2005 

NOx 

0.004 

0.003 

0.003 

0.003 

0.004 

0.004 

0.004 

0.004 

0.003 

0.003 

0.005 

0.002 

2015 

GWH* 

323332 

638079 

269496 

325957 

306134 

324629 

314908 

409210 

841504 

387049 

189876 

204287 

2015 

C02 

1.069 

1.159 

1.192 

1.111 

1.325 

1.114 

1.343 

1.206 

1.125 

1.111 

1.478 

1.126 

2015 

S02 

0.000 

0.000 

0.000 

0.000 

0.001 

0.000 

0.000 

0.000 

0.000 

0.000 

0.001 

0.000 

-

2015 

NOX 

0.002 

0-002 

0.002 

0.002 

0.003 

0.004 

0.004 

0.002 

0.002 

0.002 

0.004 

0.002 

* All GWH represent actual regional generation plus intro-regional purchases. 

(from IPM ru>».) 

Weighted Average of Emissions based on regional GWH: 

1995 

OWH* 

1995 

C02 

1995 

S02 

1995 

NOx 

2005 

GWH* 

2005 

C02 

2005 

S02 

2005 

NOx 

2015 

GWH* 

2015 

C02 

2015 

S02 

2015 

NOx 

247992 

532625 

167680 

248605 

236456 

258349 

268190 

286727 

566404 

241999 

148095 

121918 

0.088 

0.311 

0.057 

0.109 

0.141 

.088 

.097 

.128 

.303 

0.088 

0.076 

0.062 

0.000 

0.001 

0.000 

0.000 

0.001 

0.000 

0.000 

0.000 

0.001 

0.000 

0.000 

0.000 

0.000 

0.001 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.001 

0.000 

0.000 

0.000 

290079 

592182 

216896 

294818 

269174 

283306 

298198 

350135 

705252 

312385 

167978 

157912 

1.5494 0.0026 070b5S~T9383i5 

0.084 

0.203 

0.062 

0.090 

0.097 

0.083 

0.095 

0.123 

0.217 

0.095 

0.063 

0.043 

..25*0" 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

"OflOT 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.001 

0.000 

0.000 

0.000 

0.003r 

323332 

638079 

269496 

325957 

306134 

324629 

314908 

409210 

841504 

387049 

189876 

204287 

4534461 

0.076 

0.163 

0.071 

0.080 

0.089 

0.080 

0.093 

0.109 

0.209 

0.095 

0.062 

0.051 

'..1776 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.000 

0.0002 

A//V flOi)/H. tv t/tf/Tfj Sh/tS/f-t-Cs