1. Introduction
As an important factor driving economic development, energy is becoming increasingly important in the industrialization of countries [
1]. However, carbon dioxide emission caused by massive energy consumption has become the primary factor of global warming [
2]. As the world’s largest developing country, China’s energy consumption in 2021 accounted for 26.11% of the world’s total energy consumption, and its total carbon emissions accounted for 30.69% of the world’s total carbon emissions [
3]. Therefore, the twin carbon plans of peak carbon by 2030 and carbon neutrality by 2060 pledged by Chinese leader Xi Jinping at the “Waiting Ambition Summit” have attracted much global attention. Energy efficiency refers to the economic and environmental benefits obtained from a unit of energy consumption [
4]. Improving energy efficiency is important to promote economic growth and reduce greenhouse gas emissions [
5]. Therefore, it is of great theoretical value and policy guidance to seek ways to improve energy efficiency.
Due to the externalities of improving energy efficiency and solving environmental pollution, environmental regulation has become the first choice for the government to improve energy efficiency [
6]. Although the central government of China has introduced a series of emission reduction policies and strengthened investment in environmental protection, the improvement of energy efficiency in China is lagging in the world [
7]. Most scholars agree that the failure of local governments to implement environmental policies formulated by the central government effectively is the cause of ineffective environmental governance in the Chinese government [
8]. Specifically, environmental policies in China are generally “top-down,” with the central government formulating environmental policies and local governments primarily implementing them, but the responsibility for environmental governance is not included in the promotion and assessment of local officials. As a result, local governments often do not pay as much attention to environmental protection as they do to economic development, which ultimately leads to poor implementation of central environmental policies [
9,
10].
Therefore, the river chief system (RCS), as a powerful means of local environmental regulation, came into being. The RCS is a major innovative environmental protection policy independently implemented by local governments in China to promote water ecological and environmental governance. In 2007, the Wuxi city government took the lead in implementing the river chief system in response to the cyanobacteria crisis in Taihu Lake. Several local governments have since copied the policy. By 2018, the RCS had been fully implemented nationwide in China [
11]. Unlike other environmental protection policies in China, the RCS is independently proposed by local governments, which for the first time incorporates environmental protection responsibility into the assessment and promotion of local officials [
11]. In this case, local officials cannot ignore environmental pollution problems based on the pressure of assessment and promotion, so they will naturally intensify environmental protection efforts and increase environmental governance expenditure [
8]. In view of this, this paper attempts to explore the relationship between RCS, a bottom-up environmental policy developed by local governments, and energy efficiency.
However, there is little literature examining the impact of the RCS on energy efficiency. To fill this research gap, we empirically examine the impact of the RCS on energy efficiency using a multiple difference-in-differences (DID) methodology. First, we measured firms’ green total factor energy efficiency (GTFEE) based on relevant data from Chinese industrial firms. Second, we take the establishment of the river chief system (RCS) by local governments as a quasi-natural experiment. We find that the river chief system (RCS) significantly improved the GTFEE of firms. At the same time, this paper provides two ways to explore the RCS improves firms’ GTFEE mainly through two aspects: improving energy structure and enhancing technological innovation. In addition, there is heterogeneity in the policy effects of the RCS. Specifically, RCS has a greater effect on improving the GTFEE of large firms, non-exporting firms, and firms in heavily polluting industries than small firms, exporting firms, and non-heavy polluting industries.
The main contributions of this paper are as follows. First, to the best of our knowledge, this paper is the first to measure GTFEE at the firm level. For energy efficiency at the firm level, the existing literature mainly calculates the single factor energy efficiency (SFEE) at the firm level [
12,
13], but the GTFEE at the firm level was not measured. Compared with SFEE at the enterprise level, GTFEE at the enterprise level takes into account the mutual substitution of different production factors and includes undesired output, which can reflect the energy economic system efficiency of enterprises more comprehensively and effectively [
14,
15]. Second, this paper extends the research on environmental regulation and energy efficiency. The existing literature mainly examines the impact of environmental regulations on energy efficiency from two perspectives: market-oriented regulations [
16,
17] and “top-down” command-and-control regulations [
18,
19] to examine the impact of environmental regulation on energy efficiency. This paper is the first to examine the impact of environmental regulations on energy efficiency from the perspective of “bottom-up” command-and-control regulations using the river chief system as a policy, filling a gap in the existing literature. Third, we further explore the potential impact mechanism of RCS on enterprise GTFEE and analyze and confirm that RCS can improve GTFEE through two important channels: improving energy mix and enhancing technological innovation, the latter effectively verifying the existence of the “Porter effect”.
The rest of the paper is structured as follows.
Section 2 reviews the relevant literature.
Section 3 summarizes the background of the river chief system and presents the research hypothesis.
Section 4 provides an introduction to the methodology, variables, and data.
Section 5 presents the empirical results of the paper.
Section 6 presents the further analysis.
Section 7 presents conclusions and implications.
4. Methodology and Data
4.1. Methodology
Referring to the research of Ouyang et al. [
35] and Li et al. [
11], we regard the implementation of the river chief system (RCS) in cities as a quasi-natural experiment and use a staggered difference-in-differences (DID) methodology to test the impact of RCS on firms’ GTFEE. The DID methodology is an econometric method for estimating causal effects. Its basic idea is to regard public policy as a natural experiment to evaluate the net impact of a policy. Specifically, all samples are first divided into two groups, one group is affected by the policy, that is, the experimental group; the other group is not affected by the policy, that is, the control group. Then, I net impact of the policy is then obtained based on the difference in the change between the experimental and control groups before and after the policy is implemented. The specific model is as follows:
In Equation (1), represents GTFEE of firm k in industry j in ciIy i in year t. is the dummy variable. We set RCS to 1 if the cIty i has implemented RCS in year t and 0 otherwise. The coefficient suggests the impact of RCS on the GTFEE of firms. If is positive and significant, it suggests that RCS can improve the GTFEE of firms. is a series of firm-level control variables. , , , and represent city fixed effect, industry fixed effect, firm fixed effect, and year fixed effect, respectively. Among them, city fixed effects are measures of unique characteristics of each city that do not vary over time. Industry fixed effects are measures of unique characteristics of each industry that do not vary over time. Firm fixed effects are measures of unique characteristics of each firm that do not vary over time, and year fixed effects are measures of unique characteristics of each year that do not vary with other factors, such as macroeconomics. is an error term. All standard errors are clustered at the firm level.
An important premise of difference-in-difference estimation is that the samples of the experimental and control groups share a common trend of change before the implementation of the policy event. Therefore, the observed differences between the two sample groups are fragmented due to policy treatment effects. To ensure the validity of the DID model, referring to Beck et al. [
47] we next construct the following model to verify whether the samples satisfy the parallel trend assumption.
In Equation (2), is a series of dummy variables that equals 1 when there are m years away from the implementation of RCS in city i. For example, when m = 2, the dummy variable indicates that city i implemented RCS in year t + 2, which estimates the effect in the second year after the implementation of RCS. Therefore, = 1 in the second year after RCS implementation, and = 0 in other years. Similarly, when m = −1, the dummy variable indicates that city i implemented RCS in year t − 1, which estimates the effect in the first year before RCS implementation. Therefore, = 1 in the first year before RCS implementation, and = 0 in other years. We set the previous year of RCS implementation as the base year for policy implementation. We focus on the estimates of that indicates the difference in GTFEE between the treatment group and the control group m years away from the benchmark year. The meanings of other variables in model (2) remain the same as in model (1).
4.2. Variables
4.2.1. Dependent Variable
We constructed firms’ green total factor energy efficiency (GTFEE) as the dependent variable. Compared with SFEE, GTFEE can reflect energy economic system efficiency more comprehensively and effectively. Referring to Wu et al. [
14] and Gao et al. [
15], we use the undesirable-SBM model to calculate the GTFEE of firms. The undesirable-SBM model is proposed by Tone [
48], and it belongs to one of the DEA-derived models. Compared with the traditional DEA model, the undesirable-SBM model not only avoids the bias caused by radial and angular measures but also takes into account the influence of undesirable output factors in the production process, which better reflects the essence of efficiency evaluation.
To be specific, we assume that each firm is a decision-making unit (DMU), the number of which is N. We suppose each decision-making unit has M inputs, S
1 expected outputs and S
2 unexpected outputs, which can be represented in the form of matrices
. Specifically,
,
, and
are the corresponding relaxation vectors of input, expected output, and unexpected output, respectively. In addition, λ is the weight vector. The basic calculation formula is as follows:
The measurement of GTFEE mainly includes the firm’s inputs, expected outputs and unexpected outputs. The specific index selection and its measurement are shown in
Table 2. The inputs are divided into capital stock, energy consumption, and labor force. They are denoted by the total capital stock, total energy consumption, and the total number of employees of each firm. The total output value of the enterprise are selected to measure desirable output. Using energy creates maximum expected output, it also requires control to minimize environmental pollution. Therefore, we select each industrial firm’s total industrial wastewater discharge, total sulfur dioxide emission and total industrial solid waste emissions to measure the undesired output. The data from the Chinese Industrial Enterprise Database and the Chinese Industrial Enterprise Pollution Database from 2003 to 2013.
4.2.2. Independent Variable
We use to represent the independent variables, where i represents the city and t represents the year. is the dummy variable. We set RCS to 1 if the city i has implemented RCS in year t and 0 otherwise.
4.2.3. Mechanisms Variable
Energy structure: regarding Bu et al. [
13], we use coal consumption, fuel oil consumption, and clean gas consumption to reflect the change in energy structure. The RCS increases the pollution discharge cost of enterprises, which in turn prompts enterprises to optimize their energy structure [
49]. The optimization of energy structure can improve GTFEE [
43].
Technology innovation: referring to Gao et al. [
2], we use firm’s R&D expenditure as a measure of firm’s technological innovation. The RCS can force firms to engage in green innovation activities [
8,
44]. Additionally, technological innovation is an important way to improve GTFEE [
15].
4.2.4. Other Control Variables
Referring to Bu et al. [
13] and Huang et al. [
12], the control variables are as follows: (1) Firm age (FA), measured by subtracting the year of establishment from the sample year and adding 1, and then taking the logarithm; (2) firm size (FZ), measured by the logarithm of the firm’s total assets; (3) firm profit (FP), measured by the logarithm of the firm’s total profit; (4) firm debt ratio (FR), measured as the ratio of total liabilities to total assets; (5) technological innovation (TI), measured by the logarithm of the enterprise’s R&D expenditure; (6) whether the enterprise is an exporter, a dummy variable, 1 when the enterprise has an export business, 0 otherwise; (7) whether the enterprise is a state-owned enterprise, a dummy variable, 1 when the enterprise is a state-owned enterprise, 0 otherwise. Among them, the selection of control variables such as firm age (FA), firm size (FZ), technological innovation (TI), whether the enterprise is an exporter, and whether the enterprise is a state-owned enterprise is mainly based on Bu et al. [
13]. The selection of the two control variables of firm profit (FP) and firm debt ratio (FR) is mainly based on Huang et al. [
12]. We expect that the control variables of firm age (FA), firm size (FZ), firm profit (FP), technological innovation (TI), and whether the enterprise is an exporter all have positive effects on GTFEE, while the two control variables of whether the enterprise is a state-owned enterprise and firm debt ratio (FR) all have negative effects on GTFEE. Descriptive statistics of the above variables are shown in
Table 3.
4.3. Data Sources
The enterprise pollution emission data in this paper are obtained from the environmental statistics database of Chinese industrial enterprises, and the enterprise-level economic indicators are obtained from the database of Chinese industrial enterprises. In recent years, many scholars have used the above two databases to study Chinese enterprises’ economic and environmental pollution [
50,
51]. Meanwhile, this paper merges the above two databases by using the legal person code and enterprise name of enterprises as matching variables.
The sample interval in this paper is set to the period 2003-2013. The cities in the Yangtze River Delta region, where the Taihu Lake basin is located, have comparable levels of economic development, close geographical proximity, and connected governance waters. To avoid the influence of cross-regional and cross-basin factors, referring to Wang et al. [
52], we restrict our sample to firms in the Yangtze River Delta region.
The data related to the implementation of the river chief system are compiled from the documents of each municipal government. As of 2013, 22 of the 41 cities in the Yangtze River Delta region have initiated the “river chief system” policy.
Finally, this paper refers to the standard processing method of the Chinese industrial enterprise database [
53] and performs data cleaning on this database: (1) eliminating enterprises with less than 8 employees; (2) eliminating enterprises with non-positive values of gross industrial output value, current assets, fixed assets, and product sales revenue; (3) eliminating enterprises with current assets or fixed assets larger than total assets; (4) excluding enterprises with only one-year observation; (5) excluding enterprises with an asset-liability ratio less than 0. We finally obtained 35,287 valid data during the sample period.
7. Conclusions and Implications
This paper empirically examines the impact of the river chief system ( RCS) on firms’ GTFEE using data from Chinese industrial firms from 2003 to 2013. First, we measured the GTFEE of enterprises for the first time using data from Chinese industrial enterprises. Second, we used the establishment of the RCS by local governments as a quasi-natural experiment to quantitatively analyze the impact of RCS on GTFEE using a multiple DID approach. The study results are as follows: (1)the RCS can significantly improve GTFEE. The GTFEE of firms increases by about 5.3% after implementing the river chief system. The results of a series of robustness tests indicate that the findings of this study are robust; (2) the mechanism test finds that RCS can improve GTFEE by optimizing energy structure and promoting technological innovation; (3) the policy effects of the RCS show heterogeneity in terms of firm size, whether the firm exports, and whether the firm is in a heavily polluting industry. Specifically, the larger the firm’s size, the greater the effect of RCS on GTFEE enhancement. The promotion effect of RCS on the GTFEE of exporting firms is greater than that of non-exporting firms. The promotion effect of RCS on the GTFEE of firms in heavy pollution industries is greater than that of firms in non-heavy pollution industries.
This paper makes the following policy recommendations. First, the RCS is a major innovative environmental policy implemented by local governments in China and, for the first time, includes environmental protection responsibilities in the assessment and promotion of local officials. Our study finds that RCS can significantly improve firms’ GTFEE, which helps the Chinese government further improve its environmental protection management system. On the one hand, China’s central government should fully decentralize and encourage local governments to promote institutional innovation in environmental governance and become the mainstay of environmental governance. On the other hand, the Chinese government needs to include environmental responsibilities in the performance assessment of local officials when formulating other command-based environmental policies. Second, we find that RCS improves GTFEE by optimizing the energy mix. Coal accounts for more than 94% of China’s energy reserves, while oil and natural gas account for only about 6%, and this status quo determines that China’s energy consumption mix is dominated by coal [
17]. Therefore, the Chinese government should actively promote the optimization of China’s energy structure by increasing the import of oil and natural gas on the one hand, and the acceleration of the development of new energy industries on the other hand, to promote the transformation of the energy structure from coal to clean energy and renewable energy. Third, the RCS can improve GTFEE through technological innovation; therefore, the Chinese government should implement various subsidy policies and increase financial support for enterprises to carry out green innovation activities to encourage them to research and develop green technologies.
Although this paper comprehensively analyzes the relationship between RCS policy and enterprise energy efficiency, there are still some limitations. For example, it may omit the promotion pressure of officials related to RCS policy, political connections, and other factors affecting enterprise energy efficiency. Although it is impossible to explore exhaustively the factors affecting enterprise energy efficiency, this may be a future research direction. In addition, in future studies, it is also an important theoretical and practical issue worth discussing to explore how RCS policy, as environmental regulation, influences the profits of enterprises. This is because the coordination of the relationship between environmental protection and enterprise development is the internal driving force to motivate enterprises to spontaneously save energy and reduce emissions.