Coupling analysis of urbanization and energy-environment efficiency: Evidence from Guangdong province

Rapid urbanization has been accompanied by a series of environmental and energy-related issues. It is essential to better understanding the coupling relation between energy-environment efficiency and urbanization in achieving the goal of sustainable urbanization. In this paper, an index system was firstly established for the measurement of urbanization quality scores based on the four aspects of population, economy, society, and space. We then undertook a slack-based measure data envelopment analysis in order to measure energy-environment efficiency. This allowed us to establish a coupling coordination degree model to investigate the coupling relationship between energy-environment efficiency and urbanization. Our findings include the following: (1) Spatiotemporal diversity was apparent in the estimated urbanization quality scores within the province, with high-values areas mainly being concentrated in the Pearl River Delta; (2) A growth trend was identified in energy-environment efficiency values in western Guangdong and the Pearl River Delta, while in eastern Guangdong energy-environment efficiency followed a downward trend, and it stayed stable at a low level in northern Guangdong. Energy-environment efficiency also displayed significant spatial differentiation; (3) The coupling relationship between the energy-environment efficiency and urbanization of Guangdong throughout the research period went from a low coupling stage to a medium coupling stage. Most cities in Guangdong remained in the moderate and low coupling stages, with the exception of Guangzhou and Shenzhen, which took the lead in entering the highly coupling stage. The findings of this paper are of great implications for government in achieving the coordinated development of energy-environment efficiency and urbanization.