Video: Nuclear power and the fate of US air quality

As many nuclear power stations in the U.S. approach the end of their service lives, policymakers must decide whether to retire these facilities or renew their operating licenses. Nuclear power plants deliver almost 20% of the national power supply and also provide an unheralded environmental benefit explored by researchers from the University of California Davis and the Massachusetts Institute of Technology (MIT).

Past closures of nuclear facilities have resulted in increased fossil fuel use to compensate for generating capacity shortfalls. Such trends have exacerbated air pollution levels, suggesting that maintaining nuclear power output is beneficial in terms of air quality.

This conclusion was reached by means of an energy grid dispatch model developed to assess how the U.S. energy system would respond to a shutdown of nuclear power. The model simulates the production of every power plant and runs continuously to estimate, hour by hour, the energy demands in 64 regions nationwide. In line with energy market trends, the model turns a plant’s production up or down based on cost, and those producing the cheapest energy at any given time are given priority to supply the grid over more costly energy sources.

Results from different scenarios, including an energy grid with no nuclear power and a system with no nuclear power that also incorporates the additional renewable sources predicted to be added by 2030, were combined with atmospheric chemistry model output. The analysis considered emission plumes and population density to examine the risk of premature death based on degree of exposure.

Air pollution is observed to exacerbate in the absence of nuclear power capacity. The greatest air quality degradation occurs along the U.S. east coast, which hosts the most nuclear power stations. The resulting increased production from coal- and gas-fired plants is implicated in 5,200 pollution-related deaths across the country, compared to the baseline scenario.

The research is published in Nature Energy.