Impacts of biomass power generation on ambient air quality–evidence from China

With deteriorating air pollution and climate change, generating power with cleaner technologies to meet energy demand of economic development has become a crucial policy consideration globally. Biomass power generation, despite being cleaner than coal power generation, still emits certain air pollutants that can impact ambient air quality. On the other hand, biomass power plants might mitigate air pollution by reducing open-field crop burning. With this counteracting in play, it is unclear which effect is dominant and how biomass power generation affects ambient air quality eventually. We build a unique spatially high-resolution dataset for 20-km-radius circles, considering both regions with biomass power plants and those without, to explore the impacts of biomass power generation on air quality in nearby regions. By applying panel and canonical difference-in-differences models with various model specifications and estimation strategies, we demonstrate that biomass power generation in China significantly reduces ambient annual concentrations of PM2.5, PM10, SO2, and CO. The impacts on NO2 reduction could only be observed in summer, when open-field burnings decreased substantially. The impacts on PM2.5 could be observed in both summer and fall. No seasonal pattern is observed for the reductions in PM10, SO2, and CO concentrations.