Carbon dioxide emission factors for U.S. coal by origin and destination

This paper describes a method that uses published data to calculate locally robust CO₂ emission factors for U.S. coal. The method is demonstrated by calculating CO₂ emission factors by coal origin (223 counties, in 1999) and destination (479 power plants, in 2005). Locally robust CO₂ emission factors should improve the accuracy and verification of greenhouse gas emission measurements from individual coal-fired power plants. Based largely on the county origin, average emission factors for U.S. lignite, subbituminous, bituminous, and anthracite coal produced during 1999 were 92.97,91.97,88.20, and 98.91 kg CO₂/GJ_gross, respectively. However, greater variation is observed within these rank classes than between them, which limits the reliability of CO₂ emission factors specified by coal rank. Emission factors calculated by destination (power plant) showed greater variation than those listed in the Emissions & Generation Resource Integrated Database (eGRID), which exhibit an unlikely uniformity that is inconsistent with the natural variation of CO₂ emission factors for U.S. coal. ?? 2010 American Chemical Society.