The largest electric utilities in the US — including Entergy, Hoosier Energy and Xcel — have seen significant reductions in global warming pollution in recent years, according to an analysis of power plant air pollution emissions.
The report — a collaborative effort between Ceres, Bank of America, four power producers (Calpine, Entergy, Exelon, and Public Service Enterprise Group), and the Natural Resources Defense Council, authored by M.J. Bradley & Associates — comes as the EPA prepares to finalize the Clean Power Plan, which is expected to result in reductions in CO2 emissions from the electric power sector by 30 percent nationwide below a 2005 baseline by 2030.
The analysis examines CO2, nitrogen oxides (NOx), sulfur dioxide (SO2), and mercury emissions from the nation’s 100 largest electric power producers. It found that CO2 emissions from power plants decreased 12 percent from 2008 through 2013, and that the economy has continued to grow even as CO2 emissions have declined.
Southeast (Entergy and Dominion), Midwest (Hoosier Energy and Associated Electric Cooperatives) and Southwest/West (OGE and Xcel) power producers are among those achieving some of the highest levels of improvement in their CO2 emission rates (pounds per megawatt hour, lb/MWh).
On a state level, between 2008 and 2013, a large majority of states (42) decreased their electric sector CO2 emissions. These states reduced their emissions by an average of 19 percent, according to a comparison with past benchmarking reports.
While emissions overall are trending downward, the report found uneven performance across both power producers and the states. CO2 emissions rates (a measure of the carbon intensity of a power provider’s fuel mix) vary 10-fold among the top 100 producers, from a high of 2,264 pounds of CO2 per megawatt-hour of power (lb/MWh) for Big Rivers Electric in 2013, to 200 lb/MWh or less for companies such as Exelon, New York Power Authority, PG&E, and Iberdrola.
The 100 power producers evaluated in the report represent 85 percent of the electric power generated in the US and 87 percent of the industry’s air emissions.
The report also finds air pollution emissions from power plants are highly concentrated among a small number of producers. Among the 100 largest generators:
- Five (Duke, AEP, Southern, NRG, and MidAmerican) generate 25 percent of CO2 emissions, though Southern has seen a significant decline in emissions (27 percent) since 2000, and Duke has seen a 10 percent decline in its emissions rate even after its recent merger with Progress Energy.
- Three (AEP, Southern, and NRG) generate nearly 25 percent of SO2 emissions.
- SO2 and NOX emissions in 2013 were 80 percent and 74 percent lower, respectively, than they were in 1990, when major amendments to the Clean Air Act were passed.