Does energy efficiency have a spatial spill-over effect in China? Evidence from provincial-level data

The analysis of spill-over effect and mechanism is of great significance for eliminating the unbalanced development of regional energy efficiency. Our research considers the impact of external environmental factors on energy efficiency, and the spatial Durbin model is used to discover the spatial spill-over effect and mechanism. The main conclusions are as follows. (1) Eastern China is the most efficient region, central China ranks second, and west China ranks third, with a gradually descending trend in the temporal dimension. Compared to the traditional DEA model, the results removed the environmental factors to be more in line with economic intuition. (2) The spatial distribution of China's energy efficiency has a significant positive correlation from the global perspective, implying that provinces with high energy efficiency are surrounded by neighbouring provinces with high energy efficiency, and provinces with low energy efficiency are surrounded by neighbouring provinces with low energy efficiency. Provinces in each quadrant change slightly from a local perspective, indicating that energy efficiency has stable spatial correlation characteristics. (3) Neighbourhood mimicry generates a complementary effect, which promotes the spatial spill-over of energy efficiency. It is important to encourage yardstick competition and restrain lower-tier competition. (4) Industrial structure, market factors, opening-up, energy price, energy structure, and environmental regulation exert certain influences on energy efficiency.