Environmental Regulation and Green Technology Diffusion: A Case Study of Yangtze River Delta, China

As an important driver of green technology innovation, the impact of environmental regulation on the diffusion of green technology remains controversial. Taking China's Yangtze River Delta (YRD) urban agglomeration, as an example, and using green patents transfer to measure green technology diffusion, this paper analyzes the effect of environmental regulation on green technology diffusion by revealing the temporal and spatial characteristics of green technology diffusion in the YRD. The results show that: (1) Green technology transfer activities in the YRD mainly take place in Shanghai, Hangzhou, Nanjing, Suzhou, and other cities. (2) Green building technology is the most demanded technology in the green technology transfer market in the YRD. (3) The direction of green technology diffusion in the YRD has changed significantly over time. In the early stage, green technologies mainly flowed to developed cities such as Shanghai, Suzhou, and Nanjing. However, in the later stage, green technologies mainly flowed from developed cities such as Shanghai, Suzhou, and Nanjing to cities with lower economic development levels (mostly located in Anhui Province). (4) The consistency of environmental regulation among cities plays an important role in promoting green technology transfer within the YRD, which is precisely what the YRD ecological green integrated development strategy emphasizes, breaking the administrative barriers between cities in the YRD and accelerating the flow of green technology between cities.