Assessing the effects of electric mobility on urban air pollution: Evidence from NO₂ and PM₂.₅ reductions

Abstract

The rapid expansion of electric vehicles (EVs) is widely promoted as a strategy to improve urban air quality, yet empirical evidence quantifying their environmental benefits under different electricity-generation contexts remains limited. This study investigates the relationship between EV adoption and ambient concentrations of nitrogen dioxide (NO₂) and fine particulate matter (PM₂.₅), with a particular focus on the moderating role of electricity grid composition. Using a panel dataset of high-traffic urban areas, fixed-effects regression models are employed to estimate the association between monthly pollutant concentrations and EV market share, controlling for spatial and temporal confounders. Results show that increased EV penetration is associated with statistically significant reductions in NO₂ and more modest declines in PM₂.₅. Specifically, a one-percentage-point increase in EV share corresponds to an average reduction of 0.36 µg/m³ in NO₂ and 0.11 µg/m³ in PM₂.₅. A scenario-based analysis further examines air quality outcomes under varying EV adoption rates and alternative electricity grid assumptions. Findings indicate that NO₂ reductions are substantial across scenarios, whereas PM₂.₅ benefits are smaller and highly sensitive to the carbon intensity of electricity generation. Under renewable-dominant grid assumptions, projected pollution reductions are considerably larger than under fossil-heavy scenarios. Overall, the results demonstrate that EV deployment contributes meaningfully to reducing traffic-related NO₂ pollution, but its effectiveness in lowering PM₂.₅ depends critically on electricity decarbonization. The study underscores the need for integrated transport and energy policies to maximize air quality co-benefits.