How effective is the reduction of major pollutants in thermal power plants under the ultra-low emission policy?

In 2015, the Chinese government set ultra-low emission standards for thermal power to alleviate the pressure of increasing total pollutants from energy demand. This paper analyzes the policy effect of ultra-low emission in different regions based on panel data of 1202 thermal power enterprises, and the results of hierarchical linear model show that the total amount of air pollutants emitted by thermal power enterprises showed a decreasing trend during 2017 -2021, realizing the dual control of concentration and total amount. Due to the differences in primary energy structure, industrial structure and economic development level of different regions, the total emission reduction of thermal power pollutants is affected differently. First, the proportion of the region 's secondary industry in the region 's GDP is negatively correlated with the decrease of the total pollutant emission of local thermal power enterprises. Second, the higher the per capita GDP of the region, the more significant the decrease in the total amount of pollutants, economic development is conducive to pollutant emission reduction. Third, the higher the proportion of thermal power in local energy, the more obvious the reduction of total pollutant emissions of thermal power enterprises, indicating that the implementation of ultra-low emission policies in these regions is more thorough. In addition, the environmental protection tax plays a positive role in the total emission reduction, and the higher the sulfur dioxide tax rate, the more significant the reduction of total pollutants of thermal power enterprises. To further reduce the total amount of pollutants in thermal power, more coordinated efforts of environmental and economic policies are needed.