Coupling coordination of the digital-energy system and its impact on energy efficiency:Evidence from the “2+26” cities of Beijing-Tianjin-Hebei, China

Abstract

The digital economy and energy are crucial drivers of economic transformation, and the global development trend is toward the deep integration of the two. Previous studies carried out at the provincial scale, show it is difficult to grasp the change characteristics of prefecture-level cities. From the scale of urban agglomeration, energy management problems in different regions can be more accurately grasped. This study examines the Beijing-Tianjin-Hebei area and its seven surrounding regions, commonly known as the “2 + 26” cities. Panel data from 28 prefecture-level cities between 2011 and 2019 are utilized for analysis. First, the area's energy efficiency was assessed using the DEA-SBM model. Second, the development coordination relationship among the digital system and energy system is evaluated by using the coupling coordination degree model. Finally, the process of coupling coordination of digital-energy systems affecting energy efficiency was examined using a three-step stepwise regression and bootstrap mediation model. The findings demonstrate that: (1) The “2 + 26” cities' energy efficiency is considerably different. The distribution of the high efficiency zone changes from “high in the south and low in the north” to the state of radiating southward with Beijing and Tianjin as the center. (2) “2 + 26” cities are in the dynamic evolution stage of low to medium coupling degree, accounting for 89.3 % of all cities. The coupling coordination degree of digital-energy system has increased throughout the entire city by 49 %. (3) Energy efficiency improved by 64.7 % while the coupling coordination degree of the digital energy system grew by 1 %. The total effect of technical efficiency changes on energy efficiency accounted for 8.2 %. The research results could provide differentiated policy recommendations for regional energy use.