Emission Factors and Energy Prices. for Leonardo Academy s. Cleaner and Greener Program

Transcription

1 Emission Factors and Energy Prices for Leonardo Academy s Cleaner and Greener Program Prepared by Leonardo Academy Inc. For the Multiple Pollutant Emission Reduction Reporting System (MPERRS) Funding for MPERRS Was Provided by the Wisconsin Department of Natural Resources and the U.S. Environmental Protection Agency Last Updated March

2 Emission Factor Background Discussion Average All Generation and Fossil Fuel-Based Electric Generation Emissions Factors for Pollutants for Each State Different emissions factors are appropriate for different purposes. For calculating total emissions caused by a consumer s electricity use, average all generation emission rates are appropriate. Average all generation emissions rates are calculated by dividing the emissions from all generation by the total amount of electricity generated in the state. For calculating the emission reduction caused by an energy efficiency or renewable energy project, the fossil fuel generation only emission rates are appropriate. Fossil fuel generation emissions rates are calculated by dividing the emissions from the fossil fuel generation by the amount of electricity generated by fossil fuel generation in the state. Leonardo Academy believes that fossil fuel generation only emission factors provide more accurate estimates of emission reductions from energy efficiency. This is because low operating cost generation like hydroelectric generation and nuclear generation will run whenever they are available because of their low position in the generation loading order, regardless of decreases in overall energy consumption. As a result, a decrease in energy consumption from increased energy efficiency will have little or no impact on the total output of nuclear and renewable-based generation. The U.S. DOE EIA 1605(b) program [4] CO2 emission factors are average all generation emission factors. As such, Leonardo Academy believes the U.S. DOE EIA 1605(b) emission factors are best suited for calculating the total emissions from a consumer s electricity use. How location-specific should electric generation emissions factors be? Another issue in selecting emissions factors is how location-specific to make them. Because of the interconnected nature of the electric transmission and generation system, it is uncertain where the electricity used by a specific customer is actually generated. For this reason, using some kind of regional average is appropriate. Since it is likely that much of the electricity used by a consumer is produced relatively nearby, it is reasonable to use emission factors that reflect the generation mix in various regions of the country. Using emissions factors for each state or for regions that include several states is probably a reasonable compromise. Also, because many regulatory programs are implemented through State Implementation Plans, using state-based emission factors makes sense. Using emission factors calculated based on areas smaller than a state probably does not improve the accuracy of emissions reduction estimates due to the uncertainty of where the electricity being used was actually generated. In unusual circumstances such as off grid, isolated generation and customer groups, site-specific emission factors would be appropriate. Leonardo Academy developed what we thought were accurate emission factors for electricity emissions for our Multiple Pollutant Emission Reduction Reporting System (MPERRS) project. This project used different emission factors than those recommended by the U.S. DOE EIA for 1605(b) reporting, in order to also account for emission reductions from energy efficiency and renewable energy projects. 2

3 In the end, the final decision on what are the appropriate emission factors for reporters of emissions reductions will be made by the U.S. EPA and state EPAs, with input from other affected parties. This will happen when emission reduction reporting moves from a voluntary to a regulator specified system, as each pollutant is included in a regulator mandated trading program. Emission Factor Methodology In summary, the emission factors were calculated as follows. The emission factors for CO 2, SO 2, NOx, and Hg emissions in both Table 1 [State Level Electricity Emissions Factors for Calculation of Emission Reduction Benefits of Energy Efficiency and Renewable Energy (lb/kwh)] and Table 3 [State Level Electricity Emissions Factors for Calculation of Emission Footprints (lb/kwh)] were taken directly from the U.S. EPA s Emissions & Generation Resource Integrated Database s (egrid) State Data MS-Excel tables. egrid2006 version 2.1 [1] provides emissions and generation information for different strata of the power system, using data from the year egrid2006 data can be aggregated by power plant, state, company, power control area, egrid subregion, NERC region, or United States total. egrid calculated state average annual output emission rates (lbs/mwh) for the year 2004 by dividing annual net generation by state by annual emissions by pollutant type. egrid calculated state fossil fuel annual output emission rates (lbs/mwh) for 2004 by dividing annual fossil fuel net generation by state by annual emissions by pollutant type. Because the egrid s output emission rates (lb/mwh) are applied at the retail source level (i.e., by assigning emissions to usage by retail customers), emissions factors were revised upwards by a factor of 7.2% for Leonardo Academy s Cleaner and Greener Program to reflect transmission and distribution line losses. State imports and exports of electricity were not considered in the emission factors compiled in Tables 1 and 3 in this reporting guide. There is too much uncertainty within egrid regarding where imports originated and where imports were going. Because electricity flows are not usually measured on State borders, net imports and exports in egrid for states are estimated indirectly. Thus, all net imports values reported in egrid are estimates rather than measured values. Also, there is the added uncertainty of the actual generation mix of state imports and exports. Due to this uncertainty, it was determined that the possible increased accuracy to the state emission factors does not justify the additional workload necessary to incorporate imports and exports into the model. Also, State Implementation Plans are only interested at looking at emissions that are emitted within a given state and are not concerned with State imports or exports. CO 2 all generation emission factors from the US DOE EIA 1605(b) reporting system [4] are also included as a reference. Emission factors for the different fuel types listed in Tables 4, 5, and 6 were calculated using US EPA Document AP 42 [3] and the US DOE EIA 1605(b) reporting system [5]. 3

4 Table 1: State Level Electricity Emissions Factors for Calculation of Emission Reduction Benefits from Energy Efficiency and Renewable Energy (kwh) (Annual Non-Baseload Output Emission Rates, Including 7.2% Transmission and Distribution Line Losses) STATE CO2_NB* lb./kwh NOx_NB lb./kwh SO2_NB lb./kwh Hg_NB lb./kwh Hg_NB lb./mg Alabama E Alaska E Arizona E Arkansas E California E Colorado E Connecticut E Delaware E DC E Florida E Georgia E Hawaii E Idaho N/A N/A Illinois E Indiana E Iowa E Kansas E Kentucky E Louisiana E Maine E Maryland E Massachusetts E Michigan E Minnesota E Mississippi E Missouri E Montana E Nebraska E Nevada E New Hampshire E New Jersey E New Mexico E New York E North Carolina E North Dakota E Ohio E Oklahoma E Oregon E Pennsylvania E Rhode Island N/A N/A South Carolina E South Dakota E Tennessee E Texas E Utah E Vermont N/A N/A 4

5 STATE CO2_NB* lb./kwh NOx_NB lb./kwh SO2_NB lb./kwh Hg_NB lb./kwh Hg_NB lb./mg Virginia E Washington E West Virginia E Wisconsin E Wyoming E U.S. Average E *Note: NB = Non Baseload generation emission factors (Updated: 06/01/07) *These emission factors include the generation backed off by renewable energy or energy efficiency. Table 2: US DOE EIA for 1605(b) CO2 Emission Factors State CO2 lb/kwh State CO2 lb/kwh State CO2 lb/kwh Alabama 1.31 Kentucky 2.01 North Dakota 2.24 Alaska 1.38 Louisiana 1.18 Ohio 1.80 Arizona 1.05 Maine 0.85 Oklahoma 1.72 Arkansas 1.29 Maryland 1.37 Oregon 0.28 California 0.61 Massachusetts 1.28 Pennsylvania 1.26 Colorado 1.93 Michigan 1.58 Rhode Island 1.05 Connecticut 0.94 Minnesota 1.52 South Carolina 0.83 DC 1.37 Mississippi 1.29 South Dakota 0.80 Delaware 1.83 Missouri 1.84 Tennessee 1.30 Florida 1.39 Montana 1.43 Texas 1.46 Georgia 1.37 Nebraska 1.40 Utah 1.93 Hawaii 1.66 Nevada 1.52 Vermont 0.03 Idaho 0.03 New Hampshire 0.68 Virginia 1.16 Illinois 1.16 New Jersey 0.71 Washington 0.25 Indiana 2.08 New Mexico 2.02 West Virginia 1.98 Iowa 1.88 New York 0.86 Wisconsin 1.64 Kansas 1.68 North Carolina 1.24 Wyoming 2.15 Updated: 04/15/02 U.S. Average

6 Table 3: State Level Electricity Emissions Factors for Calculation of Emission Footprints (lb/kwh) (All (Total) Generation, Including 7.2% Transmission and Distribution Line) STATE CO2_TGE lb./kwh NOx_TGE lb./kwh SO2_TGE lb./kwh Hg_TGE lb./kwh Hg_TGE lb./mg Alabama E Alaska E Arizona E Arkansas E California E Colorado E Connecticut E Delaware E DC E Florida E Georgia E Hawaii E Idaho N/A N/A Illinois E Indiana E Iowa E Kansas E Kentucky E Louisiana E Maine E Maryland E Massachusetts E Michigan E Minnesota E Mississippi E Missouri E Montana E Nebraska E Nevada E New Hampshire E New Jersey E New Mexico E New York E North Carolina E North Dakota E Ohio E Oklahoma E Oregon E Pennsylvania E Rhode Island N/A N/A South Carolina E South Dakota E Tennessee E Texas E Utah E Vermont N/A N/A Virginia E

7 STATE CO2_TGE lb./kwh NOx_TGE lb./kwh SO2_TGE lb./kwh Hg_TGE lb./kwh PM10_TGE lb./kwh Washington E West Virginia E Wisconsin E Wyoming E U.S. Averages E *Note: TGE = total generation emission factors (Updated: 06/01/07) *These emission factors include all (total) generation. Table 4: Emission Factors for Natural Gas Emission Type Emission Factor lbs. per million Btu lbs. per 1000 cf 3 lbs. per Therm CO NOx N2O SO PM VOC CO Hg 0/negligible 0/negligible 0/negligible Notes on emission factors for different fuel types: Emission levels for most emission types depend mainly upon the type of fuel that is being consumed. Burning coal will release more CO 2 and SO 2 into the atmosphere than will burning natural gas for example. NOx and VOC emissions, on the other hand, are much more dependent on the combustion source and technology type or equipment used than the other emission types. Different end use appliances can release very different amounts of NOx and VOC emissions for the same amount of fuel used for each unit. The NOx and VOC emission factors used for natural gas in this reporting guide provide a good magnitude of estimation for emission levels. However, better accuracy will always be obtained by using more specific emission factors consistent with your specific project. The U.S. EPA has been performing emissions testing on many end use equipment types in recent years through their AP42 Project. Reporters may be able to find emission factors for their specific project equipment through the AP42 web site ( Where applicable, reporters should use the regulatory specified approach for determining the appropriate emission factor to use for their reporting. Care should be exercised for smaller sources not covered under the regulatory specified approach, in order to be consistent and to provide the best available emission factors to meet your combustion source and technology type. 7

8 Table 5: Emission Factors for Propane Emission Type lbs. per gallon lbs. per million Btu CO NOx N2O SO 2 * S S PM-filterable VOC(TOC) CO Hg 0/negligible 0/negligible Table 6: Emission Factors for Butane Emission Type lbs. per gallon lbs. per million Btu CO NOx N2O SO 2 * S S PM-filterable VOC(TOC) CO Hg 0/negligible 0/negligible * For SO2 emission factors for propane and butane, S equals the sulfur content expressed in gr/100 ft3 gas vapor. For example, if the butane sulfur content is 0.18 gr/100 ft3, the emission factor would be ( x 0.18) = lb of SO2/gal butane burned. Table 7: Emission Factors for Distillate Fuels Emission Type No. 6 oil No. 4 oil Residential lbs./gal lbs./mmbtu lbs./gal lbs./mmbtu lbs./gal lbs./mmbtu CO NOx SO 2 * 0.157S 1.121S 0.150S 1.071S 0.142S 1.014S PM-filterable VOC(TOC) CO Hg 0/negligible 0/negligible 0/negligible *S indicates that the weight % of sulfur in the oil should be multiplied by the value given. For example, if the fuel is 1% sulfur, then S=1. 8

9 Table 8: Average Price of Electricity to End Customers, by Sector and State, Price of Electricity Residential (cents/kwh) Commercial (cents/kwh) Industrial (cents/kwh) Alabama Alaska Arizona Arkansas California Colorado Connecticut Delaware District of Columbia Florida Georgia Hawaii Idaho Illinois Indiana Iowa Kansas Kentucky Louisiana Maine Maryland Massachusetts Michigan Minnesota Mississippi Missouri Montana Nebraska Nevada New Hampshire New Jersey New Mexico New York North Carolina North Dakota Ohio Oklahoma Oregon Pennsylvania Rhode Island South Carolina South Dakota Tennessee Texas Utah Vermont Virginia Washington West Virginia Wisconsin Wyoming U.S. Total *From U.S. DOE / EIA Electric Sales, Revenue, and Average Price 2005, Table 4. Average Retail Price for Bundled and Unbundled Consumers by Sector, Census Division, and State, [2] Released Nov. 2006, Next Release Date: Nov

10 Table 9: Average Price of Natural Gas Delivered to Residential Customers by State, Price of Natural Gas $ per MCF $ per MMBtu* $ per therm Alabama Alaska Arizona Arkansas California Colorado** Connecticut Delaware District of Columbia Florida Georgia Hawaii Idaho** Illinois Indiana Iowa Kansas Kentucky** Louisiana** Maine Maryland Massachusetts Michigan Minnesota Mississippi** Missouri Montana Nebraska Nevada New Hampshire** New Jersey New Mexico New York** North Carolina North Dakota** Ohio Oklahoma** Oregon Pennsylvania Rhode Island South Carolina South Dakota Tennessee Texas Utah Vermont Virginia** Washington West Virginia Wisconsin** Wyoming United States *From U.S. DOE / EIA Electric May 2007 Natural Gas Monthly, Table 19: Average Price of Natural Gas Sold to Residential Consumers, by State, [6] **Used average of reported months 10

11 Table 10. Average Price of Natural Gas Delivered to Commercial Customers, by State, Price of Natural Gas $ per MCF $ per MMBtu* $ per therm Alabama Alaska Arizona Arkansas California Colorado** Connecticut Delaware** District of Columbia Florida Georgia Hawaii Idaho** Illinois Indiana Iowa Kansas Kentucky Louisiana** Maine Maryland Massachusetts Michigan Minnesota** Mississippi** Missouri Montana Nebraska Nevada New Hampshire** New Jersey New Mexico New York** North Carolina North Dakota** Ohio Oklahoma** Oregon Pennsylvania Rhode Island South Carolina** South Dakota Tennessee Texas Utah Vermont Virginia Washington West Virginia** Wisconsin Wyoming** United States *From U.S. DOE / EIA Electric May 2007 Natural Gas Monthly, Table 20: Average Price of Natural Gas Sold to Commercial Consumers, by State, [6] **Used average of reported months 11

12 Table 11: Average Price of Natural Gas Delivered to Industrial Customers, by State, Price of Natural Gas $ per MCF $ per MMBtu* $ per therm Alabama Alaska Arizona Arkansas California Colorado Connecticut Delaware** District of Columbia*** Florida Georgia Hawaii Idaho** Illinois Indiana Iowa Kansas Kentucky Louisiana Maine Maryland Massachusetts Michigan Minnesota Mississippi Missouri Montana Nebraska** Nevada New Hampshire** New Jersey** New Mexico New York North Carolina** North Dakota Ohio** Oklahoma Oregon Pennsylvania Rhode Island South Carolina** South Dakota Tennessee Texas Utah Vermont Virginia Washington** West Virginia Wisconsin Wyoming** United States *From U.S. DOE / EIA Electric May 2007 Natural Gas Monthly, Table 21: Average Price of Natural Gas Sold to Industrial Consumers, by State, [6] **Used average of reported months ***Used Maryland 12

13 Notes for Natural Gas Price Tables *Used a typical heating value for natural gas of 1,050 Btu/scf per Appendix A, page 5 of U.S. EPA AP-42 Document Conversion = $/Mcf * (1000scf / 1Mcf)*(1050Btu / 1scf)*(1MMBtu / 1,000,000Btu) = $/Mmbtu Conversion = $/Mmbtu / 10 = $/therm 13

14 References [1] U.S. EPA egrid2006 Version 2.1 State File (Year 2004 Data) Released May ( [2] U.S. DOE / EIA Electric Sales, Revenue, and Average Price 2005, Table 4. Average Retail Price for Bundled and Unbundled Consumers by Sector, Census Division, and State, 2005 (cents per kilowatt hour) ( [3] U.S. EPA Office of Air Quality Planning & Standards, AP - 42 Emission Factors Supplement Documents, Update 2006, Website ( [4] U.S. DOE / EIA 1605(b) Voluntary Reporting of Greenhouse Gases Appendix G. Adjusted Electricity Emission Factors by State, February, 2002 [5] U.S. DOE / EIA 1605(b) Voluntary Reporting of Greenhouse Gases Appendix F. Fuel and Energy Source Codes and Emission Coefficients, February, 2002 [6] U.S. DOE / EIA Electric May 2007 Natural Gas Monthly, Tables 19, 20, and 21. Average Price of Natural Gas Sold to Residential (19), Commercial (20), and Industrial (21) Consumers, by State, ( Contact Information: Leonardo Academy Inc Chandler Street Madison, WI Telephone: FAX: info@cleanerandgreener.org Web Sites: