[t]he 2013 Benchmarking report is the product of a collaborative effort among Entergy, Exelon, Bank of America, Tenaska, PSEG, Pacific Gas and Electric Company, Ceres, and the Natural Resources Defense Council (NRDC), highlighting environmental performance and progress in the nation's electric power sector. The Benchmarking series began in 1997 and uses publicly reported data to compare the emissions performance of the 100 largest power producers in the United States. The current report is based on 2011 generation and emissions data. This year's report also provides state-by-state data showing states with the highest to lowest CO2 emissions.
Data on U.S. power plant generation and air emissions are available to the public through several databases maintained by state and federal agencies. Publicly- and privately-owned electric generating companies are required to report fuel and generation data to the U.S. Energy Information Administration (EIA). Most power producers are also required to report air pollutant emissions data to the U.S. Environmental Protection Agency (EPA). These data are reported and recorded at the boiler, generator, or plant level, and must be combined and presented so that company-level comparisons can be made across the industry.
The Benchmarking report facilitates the comparison of emissions performance by combining generation and fuel consumption data compiled by the EIA with emissions data on sulfur dioxide (SO2), oxides of nitrogen (NOx), carbon dioxide (CO2) and mercury compiled by the EPA; error checking the data; and presenting emissions information for the nation's 100 largest power producers in a graphic format that aids in understanding and evaluating the data. The report is intended for a wide audience, including electric industry executives, environmental advocates, financial analysts, investors, journalists, power plant managers, and public policymakers.