In this paper, the three-stage DEA method is used to measure the energy efficiency of 30 provinces and cities in China from 2010 to 2017, and the efficiency values without environmental factors and random disturbance influence are compared with the results analyzed by the traditional DEA method. The results show that before the removal of environmental factors and random disturbances, the scale efficiency of most provinces is higher than the pure technical efficiency, resulting in the overestimation of scale efficiency and the lack of investment. According to the results of three-stage DEA, China's regional scale returns show an increasing trend, thus indicating that the enterprises scale is an important factor affecting the scale diseconomy of the energy utilization. There are different efficiency degrees and function directions in different regions. The energy efficiency levels are quite different between economically developed areas and economically underdeveloped areas. The economic imbalance is obvious. Therefore, the management and technical communication and cooperation among different regions are necessary, thus promoting the technological development and improving the energy efficiency. 

Corresponding author: Leiming He, 471836222@qq.com