低碳试点城市的减碳效果及机制研究

评估低碳试点城市的减碳效果和机制路径,可以为中国实现碳达峰及碳中和目标提供重要的实践参考和依据。本文运用2007—2018年中国城市面板数据,构建多期双重差分模型并通过稳健性测试,全面考察了低碳试点政策对碳排放的影响及作用机制。研究发现：① 与非试点城市相比,低碳试点政策显著地降低了城市碳排放强度和碳排放总量;其中,试点城市的碳排放强度对比下降了4.7%,碳排放总量对比下降了7.3%。② 基于城市低碳生产、低碳生活与低碳行政三维主体行为的理论机制分析和实证研究表明：从城市低碳生产维度,生产能源节约、技术进步与推行绿色建筑解释了低碳试点政策减碳效果的60.14%;从居民低碳生活维度,生活能源节约解释了低碳试点政策减碳效果的22.17%;从低碳行政维度,缩减行政支出解释了低碳试点政策减碳效果的17.29%。③ 低碳试点城市的减碳行为具有显著的异质效应。低碳城市试点不仅加快了中国的减碳进程,也为世界控制碳排放以及缓解气候变化提供了具有中国特色的解决方案。

Policy evaluation of the low-carbon pilot cities: Effects and mechanisms

Assessing the effect of the low-carbon pilot program will be of great importance to better achieve the goals of “carbon peak” and “carbon neutrality”. This paper first measures the intensity and total amount of carbon emissions in cities of China. Then, based on the panel data of Chinese cities between 2007 and 2018, we employ a multi-period difference-in-difference model to assess how the low-carbon pilot program affects the carbon emissions among the trial cities. Our study finds the following interesting results, (1) compared with non-pilot cities, the low-carbon pilot program has significantly reduced the intensity and the total emissions of carbon in the pilot cities. Specifically, the carbon emission intensity dropped by 4.7%, and the total emissions dropped by 7.3%. It can be seen that the effect of low-carbon pilot on the total carbon emissions is better than on the intensity. Our estimation passes the parallel trend test, the placebo test, and other robustness tests, which indicates the validity of our research. (2) This paper further fully identifies three pathways from the perspectives of production activities, household activities, and government intervention. In terms of production-wise, we find that energy conservation, technology advancement and green building implementation account for 60.14% of the emission reduction effect, and low-carbon production is crucial to the low-carbon development of cities. As far as household activities concerned, energy conservation accounts for 22.17% of the emission reduction effect. In terms of government intervention, cutting administrative expenditure accounts for 17.29% of the emission reduction effect. It is important for all the three parties to adopt low-carbon actions, even if production activities have the strongest carbon reduction effect. (3) In addition, this paper finds substantial heterogeneous effect of the program. The heterogeneous effect shows that the non-resource-based cities and the cities belonging to urban agglomeration have significant emission reduction effects, indicating that the low-carbon pilot program is successful to a certain degree. It will not only accelerate China's carbon reduction drive, but also provide solutions with Chinese characteristics for the world to control carbon emissions and mitigate climate change.