Emission reduction effects of electric vehicle promotion and application pilots: Cooperative pilots vs single pilots

Previous studies have estimated the effectiveness of electric vehicle (EV) promotion policy pilots based on inter-city competition. However, the effectiveness of introducing inter-city cooperation mechanisms into these pilots remains unclear. Our study examines the EV promotion and application policy pilots initiated in 2013, focusing on “single pilots” established by single cities and “cooperative pilots” formed by groups of cities. Using panel data from 280 Chinese cities from 2003 to 2019, we employ the time-varying difference-in-differences method to analyze the carbon emission reduction effects of both single and cooperative pilots and explore potential spatial spillover effects. Results show that single pilots significantly reduce carbon emissions in the implementing cities, with this effect being more pronounced in smaller cities and those with high-speed rail systems. However, the impact of cooperative pilots is not significant. Among the single pilots, cities that participated in the previous “Ten Cities, Thousand Vehicles” pilot achieved better carbon emission reduction outcomes, but this advantage is not evident in the cooperative pilots. Furthermore, when considering the spillover effects, both single and cooperative pilots significantly promote carbon emission reduction in neighboring cities, with cooperative pilots leading to a larger spillover effect than single pilots. This study provides theoretical guidance and insights for optimizing the design of industrial policy pilots.