EPA: 2020 Power Plant Emissions Continue to Demonstrate Significant Reductions
Steady downward trend improves public health and delivers environmental benefits
WASHINGTON (February 16, 2021) — Today, the U.S. Environmental Protection Agency (EPA) released publicly available, annual data on 2020 emissions of nitrogen oxides (NOX), sulfur dioxide (SO2), carbon dioxide (CO2), and mercury from power plants in the lower 48 states. In continuation of a long-standing trend of decreasing coal generation and increasing natural gas and renewable generation, this data shows a marked decline in emissions of these key pollutants compared to 2019.
The 2020 data show a 19 percent decline in SO2 emissions compared to 2019, a 16 percent decline in NOX emissions, an 11 percent decline in CO2 emissions, and a 17 percent decrease in Hg emissions. Additionally, ozone season (May 1 to September 30) NOX emissions dropped by 10 percent. Overall, based on the first 11 months of the year, electricity demand in 2020 decreased by just over 3 percent compared to 2019. The decrease was in part due to a temporary decline in electricity demand between March and May.
From 1990-2020, annual emissions of SO2 from power plants fell by 95 percent and annual emissions of NOX from power plants fell by 88 percent. In 2020, sources in both the CSAPR annual program and the Acid Rain Program (ARP) together emitted 0.79 million tons, a reduction of 14.9 million tons, or 95 percent, from 1990 levels. In 2020, sources in both the Cross-State Air Pollution Rule (CSAPR) NOX annual program and the ARP together emitted 0.74 million tons, a reduction of 5.7 million tons, or 88 percent, from 1990 levels.
Long-term declines in emissions are due primarily to changes in the mix of fuels used in electricity generation. Data from 2020 showed a 19% decrease in coal generation and an increase in natural gas and renewable generation; this resulted in significant emissions decreases overall. This shift from higher emitting to lower and zero emitting generation has been a long-term trend and is accelerating in recent years.
These reductions protect community health. NOX and SO2 emissions contribute to the formation of ground-level ozone and particulate matter, which can lead to respiratory and cardiovascular problems, and exposure to mercury can increase the possibility of health issues ranging from cancer to immune system damage.
In addition, these emissions reductions are resulting in positive ecosystem impacts. Ambient particulate sulfate concentrations in the eastern United States have shown substantial improvement, decreasing between 47 and 83 percent from the 2000-2002 to 2017–2019 observation periods. All areas of the eastern United States have shown significant improvement in wet sulfate deposition in this period, with an overall 68 percent reduction. The level of acid neutralizing capacity, an indicator of recovery, improved significantly from 1990 levels at lake and stream monitoring sites in the Adirondacks, New England and the Catskill mountains.
EPA collects detailed SO2, NOX, CO2 , and mercury emission data and other information from power plants across the country, as part of ARP, the CSAPR, the CSAPR Update Rule, and the Mercury and Air Toxics Standards (MATS). Emissions data collected through these programs are posted online and accessible to the public at: https://www.epa.gov/airmarkets/power-plant-emission-trends