Although several of America’s biggest investor-owned utilities have seen a significant drop in their carbon footprints as they have shifted away from coal in recent years, just five––led by Duke Energy, American Electric Power and Southern––are still responsible for spewing out 25 percent of the nation’s power plant carbon emissions.
That’s a main takeaway of a comprehensive new report this week by Ceres, Natural Resources Defense Council, Bank of America and four utilities, and carried out by the Massachusetts consulting firm M. J. Bradley & Associates.
The report measures the carbon and other air pollution released by the country’s 100 largest power producers, accounting for more than a third of U.S. global warming emissions. It finds that while overall power sector emissions are declining—a trend expected to deepen under the Obama administration’s proposed CO2 crackdown, known as the Clean Power Plan—not all big utilities are rushing forward to go low-carbon.
The data also show that some of the country’s oldest and dirtiest power plants are not owned by the largest investor utilities, but by smaller government-backed rural cooperatives that have resisted the break from coal. Among the top five utilities that emit the most carbon dioxide per megawatt of electricity, four are rural cooperatives.
Cooperatives, which provide about 10 percent of U.S. electricity, are non-profits owned and operated by ratepayers that receive low-interest loans from the federal government to finance expansions and repairs. Seventy percent of their electricity comes from coal compared to roughly 37 percent for total electric utilities.
Overall, their carbon contribution is small, but not insignificant: The top seven cooperatives produced more power in 2013 than MidAmerican, the fifth-largest power producer in the country, the report shows. Combined, those seven spewed 85 million tons of carbon, 16 percent more than MidAmerican. The coal-heavy cooperatives have claimed that the Clean Power Plan, expected to be finalized in August, is illegal and would push them out of business.
Here’s a look at the top five carbon emitters, by total emissions and by carbon intensity: