Application of environmental protection investment benefit model of coal enterprises in environmental protection construction of smart city

The purpose is to strengthen the construction and application of smart environmental protection cities and establish the benefits model of enterprise environmental protection investment (EPI). This paper introduces its related concepts based on EPI and financial performance theory. It analyzes the current situation and existing problems of EPI, environmental information disclosure level (EADI), and financial performance of the coal industry and enterprises. The raw coal output and growth rate in China from 2015 to 2021, the output of major coal-producing areas from 2018 to 2021, and the revenue and profit statistics of coal enterprises from 2017 to 2021 are collected and studied. The quantitative indicators (financial performance, EPI, and EADI) are selected to verify the results. Descriptive statistics, correlation analysis, and moderating effect analysis are chosen to analyze the related explained, explanatory, intermediary, and control variables. Among them, there is an obvious positive correlation between the EPI and the EADI of coal enterprises, and the EPI of coal enterprises has a positive impact on financial performance. The EADI of coal enterprises plays a partial mediating effect on the impact of EPI on financial performance. Additionally, the correlation analysis determines the correlation between EPI, EADI, and the financial performance of coal enterprises. Finally, the regression analysis is carried out again by replacing variables. The regression results are consistent with the previous conclusions, increasing the empirical results' robustness. It is concluded that improving the EADI will give enterprises better future financial data.