低碳城市试点政策对城市能源强度的影响机制及空间溢出效应

The Impact Mechanism and Spatial Spillover Effects of Low-Carbon City Pilot Policies on Urban Energy Intensity

为科学评估我国低碳城市试点政策的节能效应,为我国推进低碳城市试点政策和加快实现节能减排目标提供经验证据和政策启示,将我国210个城市作为研究对象,运用渐进双重差分模型,并采用平行趋势检验、安慰剂、倾向得分匹配法(propensity score matching,PSM)与双重差分法(difference in differences,DID)相结合等方法进行检验,以及通过排除其他政策干扰等方法检验回归结果的稳健性,深入分析低碳城市试点政策对城市能源强度的影响机制。结果表明:相对于非试点城市,试点政策使试点城市的能源强度下降了9.744%,具有显著的节能效应,同时绿色技术创新和环境治理支出在低碳城市试点政策降低城市能源强度的影响机制作用中分别发挥了40.80%和1.62%的中介效应,其中绿色技术创新的作用更加明显,而产业结构升级的调节作用则强化了低碳城市试点政策的节能效果;另外,试点政策的节能效应在东西部城市、南方城市、经济百强城市和非资源型城市更为明显;此外,试点政策对邻近城市存在负向空间溢出效应,且具有地理衰减特征,在400 km以内(含400 km)为空间溢出区域,在400 km以外空间溢出效应不再显著。

To scientifically evaluate the energy-saving effects of the low-carbon city pilot policy,210 cities in China are selected as the research subjects.A progressive difference-in-differences model is employed,along with parallel trend tests,placebo tests,PSM-DID,and the exclusion of other policy interference to verify the robustness of the regression results and further investigate the impact mechanism of this pilot policy on urban energy intensity.The research results show that compared with non-pilot cities,this pilot policy reduced the energy intensity of pilot cities by 9.744%,which has a significant energy-saving effect,while green technology innovation and environmental governance expenditures play intermediary role in the influence of low-carbon city pilot policies reducing urban energy intensity,their intermediary effect are 40.8%and 1.62%respectively,among which the role of green technology innovation is more obvious,and the regulating role of industrial structure upgrading has strengthened the energysaving effect of low-carbon city pilot policies.Further research finds that the energy-saving effect of the pilot policy is more obvious in eastern and western cities,southern cities,top 100 economic cities,and non-resource-based cities.In addition,the low-carbon city pilot policy has a negative spatial spillover effect on neighboring cities and has geographical attenuation characteristics,the spatial spillover area is within 400 kilometers(contains 400 km),while the spatial spillover effect beyond 400 kilometers is no longer significant.The research conclusions provide empirical evidence and policy inspiration for China to promote low-carbon city pilot policies and accelerate the realization of energy conservation and emission reduction goals.