Zhang Qian, Chen Yanran
School of Economics, Capital University of Economics and Business, Beijing, China.
Sci Rep. 2025 Mar 5;15(1):7785. doi: 10.1038/s41598-025-91134-5.
This paper examines how the removal of excess coal production capacity has affected the air quality in China. A coal de-capacity policy, including a reduction in coal, downscaling of the pollution in mines, and strict regulation of coal production, was implemented in 2016. However, until now studies have paid little attention to the effects of coal de-capacity on air pollution. Using panel data from 294 cities covering from 2014 to 2020, we employed a continuous Differences-in-Differences (DID) method to show that coal de-capacity significantly reduces Particulate Matter 2.5 (PM2.5). This finding is robust to using alternative indicators, Instruments Variable (IV) and the Propensity Score Matching with Differences-in-Differences (PSM-DID) method. The heterogeneity analysis suggests that the coal de-capacity policy has a larger effect on eastern, northern cities, and those with higher initial PM2.5 and a heavier industrial base. The PM2.5 deduction is caused by cleaning coal production under the coal de-capacity. These findings provide new knowledge on the environmental benefits of coal de-capacity and demonstrate the environmental benefits of Chinese supply-side reformation.
本文研究了淘汰过剩煤炭产能对中国空气质量的影响。2016年实施了一项煤炭去产能政策，包括减少煤炭产量、降低煤矿污染以及严格监管煤炭生产。然而，到目前为止，研究很少关注煤炭去产能对空气污染的影响。利用2014年至2020年294个城市的面板数据，我们采用连续双重差分（DID）方法表明，煤炭去产能显著降低了细颗粒物（PM2.5）。这一发现对于使用替代指标、工具变量（IV）以及倾向得分匹配双重差分（PSM-DID）方法而言是稳健的。异质性分析表明，煤炭去产能政策对东部、北部城市以及初始PM2.5较高且工业基础较重的城市影响更大。PM2.5的下降是由煤炭去产能下的清洁煤炭生产导致的。这些发现为煤炭去产能的环境效益提供了新知识，并证明了中国供给侧改革的环境效益。
