Spatio-temporal dynamics and determinants of new energy policy diffusion in China: A policy citation approach

New energy policies (NEPs) have become an effective administrative means to manage the energy market and incentivize the development of the new energy sector. To reveal how and why NEPs are differentially diffused in geographic space, this study proposes a quantitative citation-based approach for exploring NEP diffusion from a spatial-temporal perspective. By identifying a wealth of policy citation links implicit in 7,375 China's NEP documents, we first illustrate spatial structures and locational dynamics of NEP diffusion, while empirically investigating driving factors that shape the spatial-temporal heterogeneity of NEP diffusion. The results indicate that: (i) the top-down pattern is the most critical spatial pattern of NEP diffusion in China, with the highest diffusion speed, diffusion intensity, and policy innovation degree; (ii) NEP diffusion exhibits a rapidly increasing trend, accompanied by the gradually strengthening spatial pattern of the "eastern>central>western"; (iii) some local socioeconomic, contextual, and energy usage conditions are responsible for the spatial heterogeneity of policy diffusion. Our study provides valuable implications for policymakers to strategically craft adequate policymaking and differentiated promotion strategies for new energy sustainability.