在中国的工业化进程中，高耗能行业发展迅速，为经济增长作出了重要的贡献，但其发展呈现“高投入、高消耗、低产出”的模式，造成了能源浪费、环境污染等问题，化石能源的大量使用也导致二氧化碳排放量大幅增加，制约了中国的可持续发展。2011年，国家出台节能降耗政策对高耗能行业的发展进行管控，力图促进高耗能行业向高效绿色转型。随着“碳达峰”与“碳中和”目标的提出，节约能源与减少碳排放协同增效的重要性也越发凸显。因此，探究针对高耗能行业的节能降耗政策是否取得了理想的政策效果意义重大，有助于促进中国高耗能行业的绿色低碳发展。

基于此，本文旨在研究节能降耗政策对高耗能行业能耗强度及碳排放强度的影响效果及作用机制。首先，依据已有文献研究以及相关理论，本文构建了理论影响机制的框架。其次，本文基于中国2007—2018年的工业行业面板数据采用双重差分法探究节能降耗政策对高耗能行业能耗强度及碳排放强度的整体影响情况和各年的政策效果差异。此外，本文分别探究了节能降耗政策对六个高耗能行业产生的异质性作用。最后，通过实证验证节能降耗政策影响高耗能行业能耗强度和碳排放强度的能源消费结构优化机制以及行业规模调整机制。

本文研究得出以下结论：第一，在通过平行趋势假设检验以及一系列稳健性检验的基础上，节能降耗政策能显著降低高耗能行业的能耗强度及碳排放强度。第二，节能降耗政策降低高耗能行业能耗强度的作用效果在2011—2016年呈现逐年增强的趋势，2017年政策效果略微减弱，2018年又有所增强。而节能降耗政策对高耗能行业碳排放强度的影响存在一定的滞后性，政策在2011—2012年期间并未产生显著的作用效果，从2013年开始政策降低高耗能行业碳排放强度的效果逐年增强。第三，节能降耗政策对非金属矿物制品业能耗强度和碳排放强度的降低效果最为明显，其次是黑色金属冶炼和压延加工业，对化学原料和化学制品制造业的降低效果最弱。政策对石油、煤炭及其他燃料加工业、有色金属冶炼和压延加工业的能耗强度和碳排放强度并未产生显著的政策作用。节能降耗政策实施后，电力、热力生产和供应业的能耗强度和碳排放强度有所升高，这可能是由于近年来中国在基础建设领域重点支持电力、热力生产和供应业的发展，使得该行业并未将工作重心放在对节能降耗政策的贯彻执行上，忽略了节能降耗的重要性，行业发展模式不够精细、发展质量不够高，煤耗、电耗在近年同步上升，导致其能耗强度和碳排放强度不降反升。第四，节能降耗政策通过优化高耗能行业的能源消费结构以及调整行业规模两个影响机制来降低能耗强度和碳排放强度。

基于以上研究结论，本文提出以下政策建议：首先，应加大节能降耗政策实施力度，多措并举助力高耗能行业节约能源与减少碳排放。其次，应该根据不同高耗能行业的特征制定更具针对性的差异化政策。再次，应该推动能源消费结构优化，降低工业行业对化石能源的过度依赖；同时调整工业行业内部结构，抑制高耗能行业盲目扩张。最后，应该多方发力，通过多主体共同推动节能和降碳相关工作。

In the process of China's industrialization, high-energy consuming industries have developed rapidly and made important contributions to economic growth, but their development presents a form of "high input, high consumption, and low output", resulting in excessive energy waste and environmental pollution. The extensive use of fossil fuels has also led to a significant increase in carbon dioxide emission, which restricts China's sustainable development. In 2011, the country introduced energy conservation and consumption reduction policy to control the development of high-energy consuming industries, aiming to promote the transformation of high-energy consuming industries to efficient and green. With the proposal of "carbon peak" and "carbon neutrality" goals, it has become increasingly important to save energy and reduce carbon emission in a synergistic manner. Therefore, exploring whether energy conservation and consumption reduction policy targeting high-energy consuming industries has achieved ideal policy results is of great significance, which helps promote the green and low-carbon development of China's high-energy consuming industries.

Based on this, this paper aims to study the impact effect and action path of the impact of energy conservation and consumption reduction policy on the energy consumption intensity and carbon emission intensity of high-energy consuming industries. Firstly, according to the existing research literature and theory, the theoretical impact mechanism framework is constructed. Then, based on China's industrial panel data from 2007 to 2018, the double difference method is used to explore the overall impact of energy conservation and consumption reduction policy on energy consumption intensity and carbon emission intensity of high- energy consuming industries and the differences in policy effects in each year. In addition, this paper explores the heterogeneous effects of policy on six high-energy consuming industries. Finally, empirical verification is conducted on the theoretical mechanism of the impact of energy conservation and consumption reduction policy on the energy consumption intensity and carbon emission intensity of high-energy consuming industries.

Here are the main conclusions: Firstly, on the basis of parallel trend hypothesis test and a series of robustness tests, energy conservation and consumption reduction policy can significantly reduce the energy consumption intensity and carbon emission intensity of high-energy consuming industries. Secondly, the role of energy conservation and consumption reduction policy in reducing the energy consumption intensity of high-energy consuming industries showed a gradually increasing trend from 2011 to 2016. The policy effect slightly weakened in 2017 and improved again in 2018. However, there is a lag in the impact of policy on carbon emission intensity, and there was no significant policy effect between 2011 and 2012. The effect of reducing carbon emission intensity has been increasing year by year since 2013. Thirdly, the energy conservation and consumption reduction policy has the most significant effect on reducing the energy consumption intensity and carbon emission intensity of the non-metallic mineral product industry, followed by the ferrous metal smelting and rolling processing industry, with the weakest effect on reducing the energy consumption intensity and carbon emission intensity of the chemical raw material and chemical product manufacturing industry. The policy has not had a significant policy effect on the energy consumption intensity and carbon emission intensity of the oil, coal, and other fuel processing industry, as well as the non-ferrous metal smelting and rolling processing industry. After the implementation of the energy conservation and consumption reduction policy, the energy consumption intensity and carbon emission intensity of the electric power, heat production and supply industry have increased. This may be because in recent years, China has focused on supporting the development of the electric power, heat production and supply industry in the field of infrastructure construction. As a result, the industry has not focused on the implementation of the policy, ignoring the importance of energy conservation and consumption reduction. The development model is not precise enough, and the development quality is not optimized enough. Coal and electricity consumption have increased simultaneously, and the energy consumption intensity and carbon emission intensity have not decreased but increased instead. Fourthly, energy conservation and consumption reduction policy can reduce the energy consumption intensity and carbon emission intensity of high-energy consuming industries by optimizing the energy consumption structure and adjusting the scale of industries.

Based on the above conclusions, here are the suggestions of this paper: firstly, efforts should be made to strengthen the implementation of energy conservation and consumption reduction policy, and multiple measures should be taken to help high- energy consuming industries save energy and reduce carbon emission. Secondly, more targeted differentiated policies should be formulated based on the characteristics of different high-energy consuming industries. In addition, efforts should be made to optimize the energy consumption structure and reduce excessive dependence on fossil fuels; At the same time, adjust the internal structure of the industry to suppress the blind expansion of high-energy consuming industries. Finally, efforts should be made from multiple parties to jointly promote energy conservation and carbon reduction related work.