Carbon dioxide emissions from the U.S. power sector fell 10 percent between 2019 and 2020, according to the 17th and latest edition of Benchmarking Air Emissions of the 100 Largest Electric Power Producers in the United States, which was released last week. The drop is the largest year-over-year decrease in greenhouse gas emissions since the initial report was issued in 1997. Further, CO2 emissions are shown to be down 20 percent from 1990 levels and 40 percent from their 2007 peak.
The 48-page analysis—which combines generation and fuel consumption data from the Energy Information Administration with emissions data on CO2, sulfur dioxide (SO2), nitrogen oxides (NOx), and mercury from the Environmental Protection Agency—was authored by M.J. Bradley & Associates, a consulting firm focused on energy and environmental issues. Listed as “contributors” to the report are Bank of America, the nonprofit organization Ceres, energy producers Entergy and Exelon, and the Natural Resources Defense Council.
It wasn’t just the pandemic: “In 2020, the U.S. electric system continued its general shift away from coal toward lower and zero-emitting sources,” the report states. “For the fourth consecutive year, natural gas was the leading source of electricity generation in the U.S. (40 percent), followed by nuclear (20 percent).”
Zero-carbon resources were responsible for about 38 percent of U.S. electricity in 2020, an all-time high, according to the report, with nuclear making up 52 percent of that. Other power sources in the carbon-free generation mix last year included renewables (wind, solar, and geothermal) at 29 percent and hydro at 19 percent. As a share of total electricity production between 2019 and 2020, zero-carbon power increased 6 percent.
Also of note: Other key findings in the report include:
- Reduced emissions and economic growth can go hand in hand. Between 2000 and 2020, power-sector CO2 emissions decreased 37 percent while GDP grew 40 percent.
- For the electric sector overall, power plant SO2 and NOx emissions were 95 percent and 88 percent lower, respectively, in 2020 than they were in 1990, when Congress passed major amendments to the Clean Air Act.
- Non-hydro renewables made up 11 percent of total U.S. generation in 2020. Of that, 20 percent came from solar, 76 percent from wind, and 4 percent from geothermal sources.
- Mercury air emissions from power plants, as reported to the EPA’s Toxic Release Inventory database, have decreased 92 percent since 2000.
Testimonial: “The benchmarking air emission report is an important measure of the progress we have made in addressing climate change by maintaining investment in renewable energy and existing carbon-free nuclear resources,” said Kathleen Barron, Exelon’s executive vice president of government and regulatory affairs and public policy. “As the nation’s largest producer of zero-emission electricity, we believe it’s critical that policymakers and power companies work together to ensure that competitive power markets recognize the value of new and existing clean energy sources that are essential to addressing the climate crisis and reducing the health impacts of air pollution, which disproportionately affect underserved communities.”