Phasing out coal power plants based on cumulative air pollution impact and equity objectives in net zero energy system transitions

Abstract

Transitioning to a net zero economy entails rapidly retiring U.S. coal power plants, a major source of both greenhouse gases and air pollution. Conceptualizations of just transitions often embed climate, socioeconomic, and environmental justice objectives. Here we evaluate historical and future cumulative air pollution impact and equity objectives in the context of coal electric power plant retirements. Operating coal power plants accounted for approximately 11,600 mortalities ($100B in damages) in 2018, disproportionately impacting low income, nonwhite, and rural populations. To evaluate the future phase-out of coal generators, we optimize for alternative climate policy goals as well as air pollution objectives related to the distribution of impacts on the basis of income, race, voting patterns, population density, and National Ambient Air Quality Standards classifications. With policy goals to achieve net zero emissions by mid-century and to minimize cumulative air pollution-related mortality, approximately 134,000 deaths ($1.2T) are avoided from 2020 to 2050 (relative to business-as-usual). We find that the way in which equity objectives are operationalized has a large influence on asset-level retirement decisions and policy design. Phase-out strategies associated with policy objectives to minimize cumulative mortalities across the U.S. population are generally consistent with objectives to minimize impacts on vulnerable subpopulations, but differ from those that target specific environmental justice communities.

Exploring Regional Fine Particulate Matter (PM2.5) Exposure Reduction Pathways Using an Optimal Power Flow Model: The Case of the Illinois Power Grid

“…Baseline exposure damages are on the order of $1.9 B/y, more than half of which occur across state lines. Accounting for exposure damages in the OPF results in a 70% reduction in damages relative to baseline conditions, which is a reduction magnitude in accordance with previous studies minimizing EGU-related damages from PM 2.5 exposure (e.g., 50%, 11%–66%, 60%–90%, 80%). Reductions are achieved by dispatching low-emission EGUs located in low- iF zones.…”

“…Next steps should also incorporate equity considerations into the reduction strategies. Previous studies ,,, have used optimization techniques to assess and reduce the exposure disparity for disadvantaged groups, and the OPF framework can be augmented with such capabilities. Equity consideration should be incorporated into exposure mitigation plans of all infrastructure to ensure that reducing absolute exposure does not come at the expense of increasing the exposure disparity for disadvantaged groups. ,,,− …”

“…The health, economic, and equity implications of PM 2.5 exposure due to electricity generation in the United States have been assessed in previous work. − The effects of intervention strategies for reduced PM 2.5 exposure such as fuel-switching, optimal plant siting, and higher renewable integration have also been studied at a national scale. Analyzing these effects has led to the development of variations of economic dispatch (ED) models with integrated health and climate components.…”

The state of macro-energy systems research: Common critiques, current progress, and research priorities

“…For example, the current MES optimization literature increasingly acknowledges the importance of objectives beyond cost-minimization when developing portfolio recommendations for “optimal” energy systems, 5 including distributional effects that have long been a focus of the social science MES literature. 6 Other examples include collaborations between modelers and public policy researchers to improve policy realism in energy models. 7 , 8 …”

Air pollution disparities and equality assessments of US national decarbonization strategies

“…Luo et al 36 investigate the air pollution benefits across different demographic groups in Texas by internalizing health impacts in energy planning. Mayfield 37 investigates the air pollution impacts on mortalities based on future coal plant retirements under two scenarios (no policy change and net zero) and across different demographic groups using a multi-objective energy and equity model. Burtraw et al use a capacity expansion model tied to a reduced complexity model to investigate the air pollution benefits of reaching climate goals by 2030 across counties and different demographic groups.…”