Emissions Reductions at Coal Power Plants Continue to Offer Routes to Meet New US PM_2.5 Standards

The 2024 revision of the National Ambient Air Quality Standard for particulate matter less than 2.5 μm diameter (PM_2.5) to 9 μg/m³ by the US Environmental Protection Agency (EPA) has motivated an assessment of whether reducing Electric Generating Units (EGU) emissions is a potential strategy for bringing nonattainment counties into compliance. We assessed coal power plants' contributions to PM_2.5 using a chemical transport model. We identified the contribution of specific coal EGUs to PM_2.5 concentrations using a reduced complexity air quality model and demonstrated health benefits of emissions reductions at facilities that would need to shutter to attain the new standard. In 2023, 9 nonattainment counties could have met the standard by eliminating SO₂ emissions at 94 facilities (9% of US EGU capacity). Retiring these EGUs would avoid stack emissions of 500,000 tons of SO₂, 304,000 tons of NO_x, and 485 million tons of CO₂, along with approximately 1,170 premature deaths per year (95% confidence interval: 1,060-1,280) among elderly people. Reducing coal power plant emissions continues to provide an avenue to meet U.S. air quality standards and improve public health.