Prioritizing closing coal-fired power plants near vulnerable communities could significantly improve air quality and public health outcomes, according to a new multi-institutional study. Using advanced computational modeling, the researchers found that existing strategies for retiring coal plants could be updated to deliver greater benefits to communities that have historically been the most impacted by pollution.
The study was published in Environmental Science & Technology.
"The study suggests that prioritizing coal plant closures based on health and equity benefits could shift state and regional strategies towards those that yield health and air quality benefits, especially for vulnerable communities, rather than focusing solely on economic factors," said Carla Campos, a civil and environmental engineering doctoral student at Penn State and a co-lead author of the study.
Since 1961, electric power plants have been the dominant consumer of coal in the U.S., according to the U.S. Energy Information Administration. However, that amount has been declining. In 2023, coal accounted for 16% of electricity generation, down from 50% in 2000. This trend follows growth in economically competitive generation from natural gas and renewables; stricter federal environmental rules aimed at reducing pollution from fossil fuel-fired power plants; federal calls for 100% carbon-free electricity by 2035; and other local, state and regional efforts to incentivize renewables and reduce emissions, such as the Regional Greenhouse Gas Initiative, a multi-state program aimed at capping carbon dioxide emissions. In 2023, renewables provided more than 20% of the electricity in the U.S.
According to the Institute for Energy Economics and Financial Analysis, the U.S. will close about half of its coal-fired plants by 2026 - a trend that is mirrored in Pennsylvania, researchers said.
"Optimizing coal-fired power plant closures based on climate, cost or health objectives can lead to substantial variation in both the magnitude and distribution of health benefits," Campos said. "This motivated us to understand the equity implications of coal plant retirements - in particular, how to better design coal retirements so as to more effectively mitigate disproportionate environmental burdens historically borne by disadvantaged communities."
Using 2019 operations as a baseline, the researchers developed and modeled six retirement scenarios spanning two targets and three priorities for Pennsylvania's coal-fired power plant operations. To assess availability and operational trade-offs, three scenarios were based on a target of retiring 50% of Pennsylvania's coal-fired capacity, or the maximum amount of electricity a power plant can produce based on its design. Three more scenarios were based on a target of retiring 50% of Pennsylvania's coal-fired generation, or the annual electricity output of a power plant.
For each target, priorities were defined as cost, climate and environmental justice (EJ). EJ focuses on improving health and environmental outcomes in low-income and low-wealth communities and communities of color that have historically and currently "bear a disproportionate share of detrimental environmental impacts with accompanying adverse health impacts," according to Pennsylvania's Department of Environmental Protection. EJ areas in Pennsylvania are now determined by more than 30 indicators, but in 2019, they were defined as census tracts where at least 20% of residents lived below the poverty line and at least 30% of the population identified as a non-white minority.
