High-speed rail, technological improvement, and carbon emission efficiency

Reducing carbon emissions and improving carbon efficiency are global responsibilities, and high-speed rail (HSR), as a new form of transportation infrastructure, plays a crucial role in this process. This paper employs the difference-in-difference model to assess the impact of HSR connectivity on carbon emission efficiency. The results show that HSR connectivity, as well as the number of stations and routes, increased carbon emission efficiency by 0.4%, 0.2%, and 0.3%, respectively. The effect is more pronounced in smaller cities and regions with lower marketization. Micro-level data reveals that the effective impact radius of HSR is 2000 m. HSR increases fossil energy consumption in firms while reducing electricity consumption. The primary mechanism by which HSR reduces overall carbon emissions is by improving the fossil energy carbon emission efficiency of firms. Parallel trend tests, placebo tests, and endogeneity analyses all support these findings. The results provide valuable insights for the location of industrial parks near HSR stations and highlight that power rationing may limit the speed of carbon reduction.