Exploring how green location-oriented industrial policies promote urban energy efficiency: evidence from National eco-industrial demonstration parks in China

Enhancing energy efficiency is a critical pathway toward achieving energy conservation, emissions reduction, and green development. However, traditional location-oriented industrial policies, while promoting economic growth, are often accompanied by issues such as a high proportion of energy-intensive industries and an unreasonable energy consumption structure. In contrast, green location-oriented industrial policies, exemplified by the National Eco-industrial Demonstration Parks (NEDPs) play a significant role in enhancing energy efficiency. Against this backdrop, grounded in theories such as market failure, Porter hypothesis and the pollution haven hypothesis, this study employs panel data from 196 Chinese cities between 2005 and 2020 and applies a time-varying difference-in-differences (TV-DID) approach to analyze the impact of NEDPs on urban energy efficiency. The results reveal that NEDPs serve as an effective policy instrument for boosting urban energy efficiency. This enhancement operates primarily through three mechanisms: the strengthening of environmental regulation, the promotion of green technology innovation, and the facilitation of industrial structure upgrading. A further investigation into the heterogeneity of the data indicates that the positive impact is more pronounced in cities that are not old industrial bases, non-resource-based, or those where the parks have already been established. Conversely, the impact is less pronounced in conventional industrial cities, resource-dependent cities, and those where parks are still under development. This paper puts forward several policy implications, including the acceleration of the green transformation of traditional development zones, the design of differentiated green industrial policies tailored to urban types, and the promotion of regional collaborative governance.