Economic level, environmental regulation, and new energy industry development.

Using panel data of 30 provinces and new energy (NE)-listed enterprises in China from 2011 to 2020, this paper uses basic model to research the impact of various environmental policies in China on NE industry development firstly. Then, using economic level as a threshold variable, a threshold model was constructed to research the impact of economic level on the relationship between environmental regulation and NE industry development. The research results show that firstly, various environmental policies in China have significantly promoted the development of the NE industry. This is mainly manifested in two aspects. One is environmental regulations significantly increased the NE industry output value and profit, the other is environmental regulations enhanced the NE industry growth potential. Secondly, the regional economic level has a significant impact on the relationship between environmental regulations and NE industry development. The promotion effect of environmental regulations on NE industry development depends on the regional economic level. When the regional economic level exceeds the threshold, the promoting effect of environmental regulations on NE industry development significantly increases. The reason is that a weak economic foundation will affect investment in the NE industry. Insufficient capital investment will inevitably seriously hinder the development of the NE industry. Thirdly, residents' education status, financial support, and NE industry agglomeration degree have a positive impact on the development of the NE industry, while population size has no significant impact on NE industry development.