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I. Carbon and CO2 ConversionsIIII.. Emissions FactorsIII. Global Warming PotentialsIV. Other ConversionsV. Energy and Emission Reduction EquivalentsVI. Emissions Related to Energy UseVII. Facts (by sector)VIII. List of AbbreviationsIX. Glossary

Compiled by ICF Consulting

November 23, 1999

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I. Carbon and CO2 Conversions:

To Convert To Multiply By

Carbon (tons) CO2 (tons) 3.67 or 44/12

CO2 (metric tons) CO2 (tons) 1.102

CO2 (pounds) CO2 (metric tons) 4.535 x 10-4

CO2 (billion pounds) Carbon (million metric tons);often expressed as MillionMetric Tons CarbonEquivalent (MMTCE)- seeglossary

0.1237

Source: U.S. DOE/EIA, 1996 Emissions of Greenhouse Gases in the United States, U.S. DOE/EIA, 1997.

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II. Emission Factors:

A. Average Marginal CO2 Emissions Factors for Electricity Generation byEPA Region (2000):

EPA Region States Within Region lbs. CO2/kWh

Region 1 MA, CT, ME, NH, RI, VT 1.726

Region 2 NY, NJ 1.679

Region 3 PA, VA, MD, WV, DC, DE 2.096

Region 4FL, NC, GA, TN, AL, SC,

KY, MS2.215

Region 5 OH, IL, MI, IN, WI, MN 1.988

Region 6 TX, LA, OK, AR, NM 1.186

Region 7 MO, IA, KS, NE 1.404

Region 8 CO, UT, MT, WY, ND, SD 1.244

Region 9 CA, AZ, NV 1.240

Region 10 WA, OR, ID 1.202

National 1.640

Source: The Cadmus Group, Inc., Regional Electricity Emission Factors Final Report, The CadmusGroup, Inc., 1998, Exhibit 6.

Notes:Average Marginal Rates are derived from modeling where the difference in emissions and demandis calculated so that the change in CO2 (lbs) divided by the change in kWh equals the AverageMarginal System Rate.

Average Rates (for NOx and SO2 that follow) are derived from dividing total in-state emissions bytotal in-state generation so that NOx (lbs) divided by kWh equals the Average State System Rate.Transmission is not accounted for.

The source for the following NOx and SO2 tables is the E-GRID (Emissions & GenerationIntegrated Database) from the EPA’s Acid Rain Program. To get lbs/kWh, divide the number by1000.

The state factors from E-GRID exclude nonutility plants for which data are not available.The national factors are based on NERC regional information that includes nonutility plant data.

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B. Average NOx Emissions Factors for Electricity by State (1996 lbs/MWh):Alabama 3.81Alaska 6.61Arizona 2.06Arkansas 2.32California 0.37Colorado 4.89Connecticut 1.50Delaware 4.93District of Columbia 3.41Florida 4.81Georgia 3.35Hawaii 6.97Idaho 0.13Illinois 4.02Indiana 6.73Iowa 4.90Kansas 4.99Kentucky 8.31Louisiana 2.79Maine 0.31Maryland 4.87Massachusetts 2.51Michigan 3.80Minnesota 4.35Mississippi 3.66Missouri 5.53Montana 1.96Nebraska 3.70Nevada 4.68New Hampshire 2.22New Jersey 3.15New Mexico 5.48New York 1.55North Carolina 5.31North Dakota 6.93Ohio 7.86Oklahoma 4.10Oregon 0.31Pennsylvania 2.93Rhode Island 3.86South Carolina 2.89South Dakota 3.25Tennessee 5.81Texas 3.05Utah 4.57Vermont 0.09Virginia 3.66Washington 0.41West Virginia 3.66Wisconsin 4.16Wyoming 5.24National 4.28Source: Emissions & Generation Integrated Database (E-GRID), EPA/Acid Rain Program.

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C. Average SO2 Emission Factors for Electricity by State (1996 lbs/MWh):Alabama 10.17Alaska 1.17Arizona 3.40Arkansas 4.37California 0.03Colorado 5.46Connecticut 4.63Delaware 10.39District of Columbia 13.90Florida 8.82Georgia 9.63Hawaii 6.60Idaho 0.00Illinois 10.25Indiana 17.15Iowa 9.50Kansas 5.88Kentucky 14.56Louisiana 3.45Maine 1.45Maryland 11.44Massachusetts 7.56Michigan 7.92Minnesota 4.18Mississippi 7.66Missouri 10.76Montana 1.32Nebraska 4.97Nevada 4.51New Hampshire 6.72New Jersey 4.61New Mexico 5.28New York 4.63North Carolina 9.07North Dakota 11.55Ohio 21.07Oklahoma 4.48Oregon 0.23Pennsylvania 11.59Rhode Island 0.03South Carolina 5.28South Dakota 2.71Tennessee 11.56Texas 4.89Utah 1.99Vermont 0.00Virginia 6.78Washington 1.40West Virginia 6.78Wisconsin 7.99Wyoming 4.93National 7.79Source: Emissions & Generation Integrated Database (E-GRID), EPA/Acid Rain Program.

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D. CO2 Emission Factors by Fuel Type per Unit Volume, Mass, and Energy:

Fuel Pounds CO2 perUnit Volume or

Mass

Pounds CO2

per million Btu(mmBtu)

Pounds Carbonper mmBtu

Million metrictons Carbon per

Quad Btu

Motor Gasoline 19.64 per gallon 157.04 42.40 19.23

824.94 per barrel

Distillate Fuel 22.38 per gallon 161.39 43.57 19.76

940.11 per barrel

Methane 116.38 per 1000 cf 115.26 31.12 14.11

Natural Gas 120.59 per 1000 cf 117.08 31.61 14.34

Coal (typical) 3723.95 per ton 212.7 57.43 26.00

Source: U.S. DOE/EIA, Instructions for Form 1605: Voluntary Reporting of Greenhouse Gases, 1998,Appendix B.

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III. Global Warming Potentials (GWP):

GWPs allow scientists and policymakers to compare the ability of each greenhouse gas to trap heatin the atmosphere relative to other gases. GWP of a greenhouse gas is the ratio of radiative forcing(both direct and indirect), from one kilogram of greenhouse gas to one kilogram of CO2 over aperiod of time, 100 years in this case as recommended by the Intergovernmental Panel on ClimateChange (IPCC) and employed for US policymaking and reporting purposes. CO2 was chosen asthe reference gas to be consistent with the IPCC guidelines.

A. List of GWPs of the six Kyoto-covered gases:

Chemical Global Warming Potential (100 Years)

CO2 1

Methane 21

N2O 310

HFCs 140-12,100

SF6 23,900

PFCs 6,500-9,200

Source: U.S. DOE/EIA, 1996 Emissions of Greenhouse Gases in the United States, U.S. DOE/EIA, 1997,Table 3.

B. To determine the carbon equivalent of a greenhouse gas:

1. Convert greenhouse gas to CO2 = MMT of GHG x GWP

2. Convert CO2 to Carbon Equivalent = CO2 x 0.27

For example:

1. 2 MMT methane x 21 (GWP of Methane) = 42 MMT CO2

2. 42 MMT CO2 x 0.27 = 11.34 MMTCE

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IV. Other Conversions:

A. Energy Unit Conversions:

To Convert To Multiply By

mmBtu Btu 106

Quads Btu 1015

kWh Wh 103

MWh kWh 103

kWh Btu 3,412 (delivered)

kWh Quads 3.412 x 10-12 (delivered)

kWh Btu 10,338 (primary)*

(10,000 is often used forconvenience)

Therms Btu 105

Horsepower (hp) kW 0.746

Btu Joule (J) 1,055

kWh Joule (J) 3.6 x 106 (delivered)

Source: U.S. DOE/EIA, Instructions for Form 1605: Voluntary Reporting of Greenhouse Gases, 1998,Appendix E.Primary kWh to Btu number from U.S. DOE/EIA, 1997 Annual Energy Review, 1998, Appendix A.* Based on this heat rate, electric generation is approximately 34% efficient.

B. Energy (Heat) Content (kWh, Btu) of Fuels (Coal, Oil, Natural Gas, andGasoline):

Fuel Energy (heat) Content (Btu)

Coal (1 ton) 2.1 x 107

Oil (1 barrel) 5.8 x 106

Natural Gas (1 cubic foot) 0.97 x 103

(1,000 is often used for convenience)

Gasoline (1 gallon) 1.2 x 105

Source: U.S. DOE/EIA, 1997 Annual Energy Review, 1998, Appendix A.

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C. Mass Conversions Between the Following:

To Convert To Multiply By

Grams Pounds 2.2 x 10-3

Pounds Grams 453.6

Pounds Tons 5 x 10-4

Tons Pounds 2,000

Tons Metric Tons 0.9072

Metric Tons Tons 1.102

Sources: U.S. DOE/EIA, Instructions for Form 1605: Voluntary Reporting of Greenhouse Gases, 1998,Appendix E, and U.S. DOE/EIA, 1998 Annual Energy Outlook, U.S. DOE/EIA, 1997, Table H2.

D. Volume Conversions:

To Convert To Multiply By

Barrels Gallons 42

Gallons Liters 3.785

Cubic Feet Liters 28.32

Source: U.S. DOE/EIA, Instructions for Form 1605: Voluntary Reporting of Greenhouse Gases, 1998,Appendix E.

E. Methane Conversions:

1 Cubic Foot (cf) of natural gas= 1,030 Btu

(1,000 is often used for convenience)

1 cf of methane= 1,012 Btu

(1,000 is often used for convenience)

1 mcf = 1 mmBtu*

1 bcf = 1 Trillion Btu*

52 Billion cf (bcf) = 1 teragram (1012 grams)

1 cf landfill gas (50% methane) = 500 Btu

Source: U.S. DOE/EIA, 1997 Annual Energy Review, 1998, Appendix B and U.S. DOE/EIA, 1996Emissions of Greenhouse Gases in the United States, U.S. DOE/EIA, 1997, Appendix E.* Based on a 1,000 Btu to 1 cf conversion

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V. Energy and Emission Reduction Equivalents:

A. Annual Emissions and Fuel Consumption for an “Average” PassengerCar:

Average CO2 emissions: 10,000 lbs/year (5 tons/year)Average fuel consumption: 556 gallons/year

Source: U.S. EPA, Annual Emissions and Fuel Consumption for an “Average”Passenger Car, U.S. EPA, 1997.

B. Average Annual CO2 Emissions for a Household:

22,750 lbs/year (11.38 tons of CO2)

Source: U.S. DOE/EIA, 1996 Emissions of Greenhouse Gases in the United States, U.S.DOE/EIA, 1997, Table 10.

The average household adds more than twice as much greenhouse gas (CO2)emissions to the atmosphere as a typical car.

C. Emission Reductions as Compared to Tree Plantings:

1 acre of forest sequesters 7,333 lbs CO2/year (3.67 tons of CO2)

Source: US EPA/APPD, calculated from DOE/EIA, Sector-Specific Issues andReporting Methodologies Supporting the General Guidelines for the VoluntaryReporting of Greenhouse Gases under Section 1605(b) of the Energy Policy Act of1992, Appendix 5E, using an average carbon sequestration rate, across tree types andland status, of 5 year old trees.

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VI. Emissions Related to Energy Use:

A. Emissions Related to Energy Use by Sector (Includes Electricity Used bySector) (1996).

The following section presents the emissions associated with energy use by each sector,which includes the emissions related to that sector’s electricity consumption.

Source: U.S. EPA, National Air Pollution Emission Trends 1900-1996, U.S. EPA, Appendix AUtility emissions distributed to sectors according to AEO 98 electricity breakdown

NOx (Thousand Tons):

Residential 2,992Commercial 2,328Industrial 5,143Transportation 11,811

SO2 (Thousand Tons):

Residential 4,579Commercial 4,623Industrial 7,521Transportation 738

NOxResidential

13%

Commercial10%

Industrial23%

Transportation54%

SO2

Residential26%

Commercial26%

Industrial44%

Transportation4%

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Source: U.S. DOE/EIA, 1996 Emissions of Greenhouse Gases in the United States, U.S.DOE/EIA, 1997, Figure 5 and Table 6.

CO2 (Million Tons):

Residential 316Commercial 254Industrial 526Transportation 517

CO 2

Residential20%

Commercial16%

Industrial32%

Transportation32%

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B. Emissions Related to Energy Use by Sector (With Utilities Separated Out)(1996).

The following section presents the emissions associated with energy use by each sector,with electric generation listed separately. Unlike Section A above, each sector’s emissionsfrom electricity consumption are included in the electric utilities sector.

NOx (Thousand Tons):

Residential 886Commercial 403Industrial 3,170Transportation 11,781Utilities 6,034

NOx

Utilities27%

Residential4%

Commercial2%

Industrial14%

Transportation53%

SO2

Utilities73%

Residential1%

Commercial3%

Industrial19%

Transportation4%

Source: U.S. EPA, National Air Pollution Emission Trends 1900-1996, U.S. EPA, Appendix A

SO2 (Thousand Tons):

Residential 180Commercial 602Industrial 3,399Transportation 675Utilities 12,604

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CO2

Utilities36%

Residential7%

Commercial4%

Industrial21%

Transportation32%

Source: U.S. DOE/EIA, 1996 Emissions of Greenhouse Gases in the United States, U.S. DOE/EIA,1997, Figure 5 and Table 6

CO2 (Million Tons):

Residential 117Commercial 71Industrial 338Transportation 516Utilities 570

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VII. Facts:

1. RESIDENTIAL SECTOR:

Total energy consumption, 1996: 19.36 QuadsEnergy Intensity, 1996: 110.9 delivered mmBtu per

householdSource: U.S. DOE/EIA, 1998 Annual Energy Outlook, U.S. DOE/EIA, 1997, Table A4.

Residential End-use Energy Consumption, 1996:

Electricity Consumption On-Site Fuel Consumption

Petroleum7%

Natural Gas28%

Other3%

Primary Electricity

62%

Source: U.S. DOE/EIA, 1998 Annual Energy Outlook, U.S. DOE/EIA, 1997, TableA2.

Residential Fuel Mix, 1996:

Space Heating

13%

Space Cooling

12%

Water Heating

10%

Refrigeration11%

Appliances24%

Lighting9%

Other Uses21%

Space Heating

76%

Water Heating

20%

Other Uses1%

Appliances3%

Source: U.S. DOE/EIA, 1998 Annual Energy Outlook, U.S. DOE/EIA, 1997, Table A4.

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Residential Energy Expenditures, sector and average household:

Sector: $124 billion (1993)$90.6 billion for electricity (1996)

Average household: $1,282 (1993)

Sources: U.S. DOE/EIA, 1993 Household Energy Consumption andExpenditures, 1995, p. vii and U.S. DOE/EIA, 1998 Annual Energy Outlook, U.S.DOE/EIA, 1997, Table A8.

Residential Emissions, 1996:

Average household: 3.1 tons of carbonAverage household: 58.8 pounds of NOx

Sources: U.S. DOE/EIA, 1996 Emissions of Greenhouse Gases in the United States,U.S. DOE/EIA, 1997, Table A4, and U.S. EPA, National Air Pollution Emission Trends1900-1996, U.S. EPA, Appendices A and B.

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2. COMMERCIAL SECTOR:

Total energy consumption, 1996: 15 QuadsEnergy Intensity, 1996: 105.3 delivered kBtu per

square footSource: U.S. DOE/EIA, 1998 Annual Energy Outlook, 1997, Table A5.

Commercial Fuel Mix, 1996:

Source: U.S. DOE/EIA, 1998 Annual Energy Outlook, 1997, Table A2.

Commercial End-use Energy Consumption, 1996:

Electricity Consumption On-Site Fuel Consumption

Source: U.S. DOE/EIA, 1998 Annual Energy Outlook, 1997, Table A5.

Petroleum5% Natural

Gas22%

Other1%

Primary Electricity

72%

Space Heating and

Cooling19%

Ventilation5%

Water Heating

5%Lighting

34%

Other Uses24%

Refrigeration4%

Cooking1%

Office Equipment

8%

Water Heating

12%

Cooking4%

Other Uses46%

Space Heating

and Cooling

38%

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Commercial Energy Expenditures, sector and per building:

Sector: $69.9 billion (1995)$75.1 billion for electricity (1996)

Building: $15,300 (1995)

Sources: U.S. DOE/EIA, 1995 Commercial Building Energy ConsumptionSurvey, U.S. DOE/EIA, 1997, Table 4 and U.S. DOE/EIA, 1998 Annual EnergyOutlook, U.S. DOE/EIA, 1997, Table A8.

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3. INDUSTRIAL SECTOR:

Total energy consumption, 1996: 34.8 QuadsSource: U.S. DOE/EIA, 1998 Annual Energy Outlook, 1997, Table A2.

Industrial Fuel Mix, 1996:

Source: U.S. DOE/EIA, 1998 Annual Energy Outlook, 1997, Table A2.

Manufacturing End-use Energy Consumption, 1994:

Electricity Consumption On-Site Fuel Consumption

Source: U.S. DOE/EIA, 1994 Manufacturing Energy Consumption Survey, U.S. DOE/EIA, 1997, TableA8.

HVAC3%

Boiler Fuel43%

Machine Drive1%

Process Heating

50%Other Uses3%

Petroleum23%

Feedstocks4%

Natural Gas29%

Coal7%

Renewable5%

Primary Electricity

32%

Process Heating

11%

Machine Drive52%

HVAC/Lighting15%

Other Uses9% Process

Cooling5%

Electro-Chemical Processes

10%

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Industrial Energy Expenditures:

$69.2 billion total (1994)$46.6 billion for electricity (1996)

Sources: U.S. DOE/EIA, 1994 Manufacturing Energy Consumption Survey, U.S.DOE/EIA, 1997, Table A17 and U.S. DOE/EIA, 1998 Annual Energy Outlook, U.S.DOE/EIA, 1997, Table A8.

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VIII. List of Abbreviations

EnergyBtu British Thermal UnitKBtu Thousand BtummBtu Million BtuTBtu Trillion BtuQuad Quadrillion BtukWh Kilowatt-hour

EmissionsGHG Greenhouse GasGWP Global Warming PotentialCE Carbon EquivalentMMT Million Metric TonsMMTCE Million Metric Tons Carbon EquivalentCO2 Carbon DioxideCH4 MethaneN2O Nitrous OxideNOx Nitrogen OxidesVOCs Volatile Organic Compounds

Othercf Cubic FeetHVAC Heating, Ventilation, and Air Conditioning

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IX. Glossary

Area Sources: Stationary and non-road sources that are too small and/or too numerous to behandled individually as point sources, but which can contribute collectively to ozone formation.Area source emissions have historically been underestimated because of few appropriate inventoryprocedures or little emphasis on obtaining area source data.

British Thermal Unit (Btu): A common unit used in measuring energy equal to the amount of heatneeded to raise the temperature of 1 pound of water by 1º F.

Carbon Equivalent: A common unit used in measuring emissions. Other greenhouse gases haveconversion factors to relate them to their equivalent amounts of carbon in order to more easilycompare emissions.

Carbon Sink: A reservoir that absorbs or takes up released carbon. Vegetation and soils arecommon carbon sinks.

Chloroflourocarbons (CFCs): A family of inert, nontoxic, and easily liquefied chemicals used inrefrigeration, air conditioning, packaging, and insulation, or as solvents or aerosol propellants.Because they are nonreactive, they drift into the upper atmosphere where they are disassociated bysolar radiation and where their components destroy ozone.

Cogeneration: The sequential use of energy to generate electricity and another form of usefulthermal energy such as heat or steam.

Conversion factor: A unique value used to convert one unit (e.g., pounds) to another appropriateunit (e.g., tons).

Criteria Pollutant: A pollutant determined to be hazardous to human health and regulated underEPA’s National Ambient Air Quality Standards. The 1970 amendments to the Clear Air Actrequire EPA to describe the health and welfare impacts of a pollutant as the “criteria” for inclusionin the regulatory regime.

Electric losses: The difference between primary electricity and delivered electricity. Losses aredue to the conversion and transportation of electric energy to the final customer.

Electricity, delivered: The amount of electric energy delivered to the final customer after electriclosses. For example, on average, it takes roughly 3,412 Btu of fuel to generate 1 kWh of deliveredelectricity.

Electricity, primary: The amount of energy (fuel) an electric generator must consume to generateand supply electric energy to consumers. For example, on average, it takes roughly 10,338(10,000 for convenience) Btu of fuel to generate 1 kWh of primary electricity.

Emission coefficient/factor: A unique value for scaling emissions to activity data in terms of astandard rate of emissions per unit of activity (e.g., pounds of CO2 emissions per barrel of fossilfuel consumed).

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Emissions: Anthropogenic releases of greenhouse gases to the atmosphere (e.g., the release of CO2

during fuel combustion).

Emissions, direct: Emissions from sources owned or leased by an entity. (e.g., on-site boilers)

Emissions, indirect: Emissions from sources not owned or leased by an entity that occur, whollyor in part, as a result of its activities. (e.g., emissions from off-site electricity generation)

Energy conservation: Activities that reduce end-use demand for energy by reducing the servicedemanded.

Feedstocks: Fossil Fuels that are used as inputs to manufacture final products and are notcombusted. These include oil used to produce asphalt and lubricants and natural gas to producenylon.

Fossil fuel: A hydrocarbon fuel, such as petroleum, derived from living matter of a previousgeologic time.

Fuel cycle: The entire set of sequential processes or stages involved in the utilization of fuel,including extraction, transformation, transportation, and combustion. Emissions generally occur ateach stage of the fuel cycle.

Fuel switching: The substitution of one type of fuel for another. The fuel substitution may beeither temporary (as in a case of a power plant that temporarily switches from coal to natural gas)or permanent (as in the case of a fleet operator who replaces gasoline-powered automobiles withelectric cars).

Greenhouse effect: A popular term used to describe the roles of water, vapor, carbon dioxide, andother trace gases in keeping the Earth’s surface warmer than it would be otherwise. Theseradatively active gases are relatively transparent to incoming shortwave radiation, but are relativelyopaque to outgoing longwave radiation. The latter radiation, which would otherwise escape tospace, is trapped by these gases within the lower levels of the atmosphere. The subsequentreradiation of some of the energy back to the Earth maintains surface temperatures higher than theywould be if the gases were absent. There is concern that increasing concentrations of greenhousegases, including carbon dioxide, methane, and man-made halogenated substances, may enhance thegreenhouse effect and cause global climate change.

Greenhouse gases: Those gases, such as water vapor, carbon dioxide, troposhperic ozone, nitrousoxide, and methane that are transparent to solar radiation but opaque to longwave radiation thuspreventing longwave radiation energy from leaving the atmosphere. Increasing levels ofgreenhouse gases in the atmosphere may contribute to an increase in average global temperaturesresulting in adverse climate changes.

Halogenated substance: A volatile compound containing halogens, such as chlorine, fluorine, orbromine.

Heat rate: A measure of the fuel required in Btu by a generator to produce one kWh of electricity.

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Intergovernmental Panel on Climate Change (IPCC): A panel established jointly in 1988 by theWorld Meteorological Organization and the United Nations Environment Program to assess thescientific information relating to climate change and to formulate realistic response strategies.

Kilowatt-hour (kWh): A common unit used in measuring power, the rate at which work is done,equivalent to 3,412 Btu per hour.

Off-Site Fuel Consumption: Fuel consumption at electric generating stations that produceelectricity to meet the needs of residences, business, and industries.

On-Site Fuel Consumption: Fuel consumed at industrial, commercial, or residential locations.Examples include a chemical manufacturer that burns natural gas in a boiler to produce steam atthe facility, or a residential consumer who burns natural gas in their hot water heater at home.

Ozone: A molecule made up of three atoms of oxygen. In the stratosphere, it occurs naturally andprovides a protective layer shielding the Earth from harmful ultraviolet radiation. In thetroposphere, it is a chemical oxidant and major component of photochemical smog.

Ozone precursors: Chemical compounds, such as carbon monoxide, methane, nonmethanehydrocarbons, and nitrogen oxides, which in the presence of solar radiation react with otherchemical compounds to form ozone.

Point Sources: Pollution emanating from a specific source such as a factory and released at aknown discharge point.

Sequestered carbon: Carbon which is removed from the atmosphere and retained in a carbon sinksuch as a growing tree or soil.

Source: U.S. DOE/EIA, 1996 Emissions of Greenhouse Gases in the United States, 1997.