Abstract: Nuclear power use in the United States is projected to decline over the coming decades. We explore how nuclear phase-outs could affect air pollution, climate, and health with both existing and alternative grid infrastructure. We develop an energy grid dispatch model to estimate the emissions of CO2, NOx, and SO2 from each electricity generating unit, coupling these emissions with a chemical transport model to calculate impacts on ground-level ozone and fine particulate matter (PM2.5). 

Our yearlong scenario removing nuclear power results in compensation by coal, gas, and oil, leading to increased emissions. We find the resulting changes in PM2.5 and ozone lead to an additional 5230 annual mortalities. Changes in CO2 emissions lead to an order of magnitude higher mortalities throughout the 21st century, incurring $50.4-$220.2 of damages from one year of emissions. A scenario exploring simultaneous closures of nuclear and coal plants shifts the distribution of health impacts, and a scenario allowing for increased penetration of renewables reduces health impacts. Inequities in exposure to pollution are persistent across all scenarios– Black or African American people are exposed to the highest relative levels of pollution, even if renewable capacity is expanded.