Danae Hernandez-Cortes (Arizona State)

"Siting, Sorting, and Socio-Demographic Change: US Power Plant Openings over the Twentieth Century"

 

Abstract: This paper examines the relative roles of initial siting decisions and post-siting demographic change in generating racial disparities in exposure to polluting fossil-fuel power plants in the United States. We combine newly digitized data on U.S. power plant siting and operations from 1900–2020 with spatially resolved population and demographic data from the U.S. Census spanning 1870–2020. We find little evidence that fossil-fuel plants were disproportionately sited in counties with higher Black population shares in most decades. In contrast, event-study estimates show that Black population share rises gradually after a county first receives a fossil-fuel plant, with average increases in Black population share of 4 percentage points in the 50-70 years after first siting. These long-run demographic shifts are driven primarily by counties that first hosted a fossil-fuel plant before 1950, consistent with the historical importance of post-siting sorting during the Great Migration and subsequent suburbanization. We couple historical fuel use and a pollution transport model to document to what extent power plant siting contributes to pollution disparities, we show that the Black-White gap in exposure to pollution from fossil-fuel power plants emerges only in the mid-20th century, peaks in the 1980s, and then narrows steadily thereafter. Overall, our findings highlight that the equity implications of siting long-lived infrastructure can differ dramatically depending on the time span considered.