ANNEX 2 Methodology and Data for Estimating CO2 Emissions from Fossil Fuel Combustion 2.1. Methodology for Estimating Emissions of CO2 from Fossil Fuel Combustion

The bottom-up methodology used by the United States for estimating CO2 emissions from fossil fuel combustion is conceptually similar to the approach recommended by the Intergovernmental Panel on Climate Change (IPCC) for countries that intend to develop detailed, sectoral-based emission estimates (IPCC/UNEP/OECD/IEA 1997). Total consumption data and adjustments to consumption are presented in Columns 2 through 13 of Table A-10. Adjusted consumption data are presented in Columns 2 through 8 of Table A-11 through Table A-29, with totals by fuel type in Column 8 and totals by end-use sector in the last rows. Fuel consumption data for the bottom-up approach were obtained directly from the Energy Information Administration (EIA) of the U.S. Department of Energy. These data were first gathered in physical units, and then converted to their energy equivalents (see the Constants, Units, and Conversions Annex). The EIA data were collected through a variety of consumption surveys at the point of delivery or use and qualified with survey data on fuel production, imports, exports, and stock changes. Individual data elements were supplied by a variety of sources within EIA. Most information was taken from published reports, although some data were drawn from unpublished energy studies and databases maintained by EIA.