Heatwaves worsen the air pollution from energy systems: Empirical evidence from balancing authorities in the United States

Climate change has led to increasingly frequent and intense heatwaves. The energy sector is particularly vulnerable to heatwaves, as they increase energy demand and reduce the efficiency of power plants, exacerbating air pollution from energy systems. This complicates the mitigation of air pollution, especially in predominantly fossil-fuel-based power systems. This study addresses this gap by providing an empirical analysis using high-frequency generation and emissions data at the balancing authority level. A fixed-effects panel regression analysis is applied to control for confounding factors and identify more causally robust effects. We find that heatwaves increase daily electricity generation by 6.73% to 7.54%, with the largest increase observed in natural gas generation at 7.7%. Additionally, heatwaves increase SO₂ emissions by 10.5% to 12.6%, NO_x emissions by 11.4% to 13.3%, and CO₂ emissions by 11.9% to 13.8%. We also detect heterogeneity among different regions, types of utilities, fuel types, and socio-demographic groups. Our study underscores the urgency of coordinated control policies to address air quality issues exacerbated by extreme temperatures.