Producer services agglomeration and energy efficiency enhancement: A serial mediation model with digital economy moderation

With the intensification of global climate change and resource constraints, improving energy efficiency has become one of the key goals for achieving sustainable development. This paper constructs a chain mediation model moderated by the digital economy, using data from 279 prefecture-level cities in mainland China between 2006 and 2021, to empirically analyze the impact of producer services agglomeration on energy efficiency and its mechanisms. The results show that producer services agglomeration significantly enhances urban energy efficiency and exhibits a threshold effect, where a higher degree of agglomeration may lead to congestion effects that weaken its positive externalities. Additionally, improvements in resource allocation efficiency and the stimulation of technological innovation form an effective chain mediation mechanism in the promotion of energy efficiency by producer services agglomeration. The rapid development of the digital economy has strengthened its positive moderating role in this relationship, with notable differences across industries. These findings reveal the multidimensional pathways through which producer services agglomeration enhances energy efficiency in the context of the digital economy.