Urban spatial structure and total-factor energy efficiency in Chinese provinces

International experience shows that the urbanization rate between 30% and 70% is a stage of rapid urban development, which means that more people in China will enter cities in the future. Along with this urbanization process, an important theoretical and practical question posed is whether China should choose a development path that is dominated by large cities or small and medium-sized cities. That is, whether China chooses a monocentric structure or a poly-centric structure, which is more conducive to the improvement of economic efficiency? The reasonable distribution of urban systems is not only a necessary condition for optimizing the spatial allocation of resources and coordinating the development of regional economies, but it is also an important source for improving total-factor energy efficiency. In this paper, a modified Super-SBM model is used to measure China?s total-factor energy efficiency. The mechanism and effect of urban spatial structure on total-factor energy efficiency is then empirically tested using the Dynamic Spatial Panel Model (DSPM). The study found that, for provinces, a poly-centric structure is more conducive to improvements in total-factor energy efficiency with research conclusions still valid following a series of robustness tests. However, the impact of urban spatial structure on total-factor energy efficiency is constrained by regional differences, development stages and city size. On the one hand, compared with the Central and Western regions, the adoption of a mono-centric structure in Eastern provinces is more conducive to improvements in total-factor energy efficiency. On the other hand, improvements in degree of both urbanization and city scale can effectively alleviate the negative impact of a mono-centric structure on total-factor energy efficiency