The advantages of clean, ecologically friendly, and renewable energy have drawn considerable attention from all nations in the world. The growth of the renewable energy industry has frequently been elevated to the status of national policy. By evaluating the technical innovation effectiveness of China’s renewable energy sector, the energy crisis may be alleviated, and the innovation potential of renewable energy can be boosted. At present, the research content of domestic renewable energy enterprises mainly adopts DEA and Cobb–Douglas production functions. Moreover, there is limited literature on the factors impacting efficiency, and most research results center on efficiency assessment. This study employs a three-step DEA method to determine the technological innovation efficiency for China’s A-share renewable energy firms from 2016 to 2020. To investigate the factors influencing technological innovation’s effectiveness, the panel Tobit model is then developed. In light of the empirical data, the main conclusions of this paper are as follows: First, despite a slow but steady improvement, Chinese renewable energy companies still need to increase their technological innovation efficiency. Pure technical efficiency is the main factor contributing to low innovation efficiency. Second, environmental laws such as reliance on global commerce, industrial structure, and local science and technology affect the innovation effectiveness of listed renewable energy enterprises. After excluding environmental factors, the comprehensive technical efficiency of listed renewable energy companies has decreased. Finally, the innovation and technological efficiency of renewable energy firms are positively impacted by government subsidies, top operational revenue, and enterprise scale.

As a typical technology-intensive industry, the renewable energy industry is a standard sample for scholars to study the R&D innovation of enterprises. At present, the industry is strongly supported by the government subsidy policy in China and has developed rapidly in recent years. Its own financing constraints and lack of innovation power are also the main problems for the development of renewable energy enterprises. Taking A-share renewable energy enterprises from 2016 to 2020 as the research object, this paper constructs a panel model to empirically study the relationship between government subsidies and enterprise innovation efficiency. The findings are as follows. First, government subsidies can significantly promote the innovation efficiency of enterprises; second, the government subsidy has an obvious double threshold effect on the innovation efficiency of enterprises, and when the government subsidy is in a certain range, the subsidy effect is the best; third, the government subsidy effect of non-state-owned renewable energy enterprises is better than that of state-owned enterprises; the effect of government subsidies for renewable energy enterprises in the central and western regions is better than that in the eastern region. The threshold effect of government subsidies on enterprise innovation efficiency is also quite different.