City Centrality, Size and Energy Efficiency

Improving the energy efficiency in the urbanization process is particularly important for China to pursue high-quality economic growth. Urbanization may change a city’s spatial structure, transforming it from a monocentric city to a polycentric one. Based on the panel data of China’s prefecture-level cities from 2002 to 2016, this article attempts to reveal the impact of urban spatial structure on energy intensity, by focusing on the role of the centrality of urban space and city size. We carefully constructe a centrality index to indicate what the urban spatial structure of a city is like, such as polycentric or monocentric. We find that the monocentric structure is associated with low energy intensity, and city size plays a significant moderating role in the causality relationship between the centrality and energy intensity. That is, an increase in city size would significantly reduce the negative effect of monocentricity on energy intensity. The heterogeneity analysis shows that monocentric structure may improve more energy efficiency in the cities without a rail transit system than in the cities with rail transit. By contrast, for polycentric cities, the development of a rail transit system helps to alleviate the decline in energy efficiency caused by the polycentricity. We find that promotion of innovation and alleviation of traffic congestion are both effective ways by which the monocentric structure improves the energy efficiency of a city