Comparison of two U.S. power-plant carbon dioxide emissions data sets

Environmental Science & Technology
By:  and 



Estimates of fossil-fuel CO2 emissions are needed to address a variety of climate-change mitigation concerns over a broad range of spatial and temporal scales. We compared two data sets that report power-plant CO 2 emissions in the conterminous U.S. for 2004, the most recent year reported in both data sets. The data sets were obtained from the Department of Energy's Energy Information Administration (EIA) and the Environmental Protection Agency's eGRID database. Conterminous U.S. total emissions computed from the data sets differed by 3.5% for total plant emissions (electricity plus useful thermal output) and 2.3% for electricity generation only. These differences are well within previous estimates of uncertainty in annual U.S. fossil-fuel emissions. However, the corresponding average absolute differences between estimates of emissions from individual power plants were much larger, 16.9% and 25.3%, respectively. By statistical analysis, we identified several potential sources of differences between EIA and eGRID estimates for individual plants. Estimates that are based partly or entirely on monitoring of stack gases (reported by eGRID only) differed significantly from estimates based on fuel consumption (as reported by EIA). Differences in accounting methods appear to explain differences in estimates for emissions from electricity generation from combined heat and power plants, and for total and electricity generation emissions from plants that burn nonconventional fuels (e.g., biomass). Our analysis suggests the need for care in utilizing emissions data from individual power plants, and the need for transparency in documenting the accounting and monitoring methods used to estimate emissions.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Comparison of two U.S. power-plant carbon dioxide emissions data sets
Series title Environmental Science & Technology
DOI 10.1021/es800221q
Volume 42
Issue 15
Year Published 2008
Language English
Contributing office(s) Woods Hole Coastal and Marine Science Center
Description 6 p.
Larger Work Type Article
Larger Work Subtype Journal Article
Larger Work Title Environmental Science and Technology
First page 5688
Last page 5693
Country United States
Google Analytic Metrics Metrics page
Additional publication details