Does Renewable Energy Technology Innovation Enhance Carbon Productivity? Evidence from China

Renewable energy technology innovation (RETI) is an effective means of reducing emissions without sacrificing productivity, making it a key driver of carbon productivity (CP) improvement. This study employs a dataset covering 30 Chinese provinces from 2010 to 2021 to empirically examine the impact of RETI on CP. Additionally, it explores the non-linear effects of environmental regulation (ER) and R&D investment (RD) in this relationship. The findings indicate that RETI significantly enhances CP, a result that remain robust across multiple robustness and endogeneity tests. The heterogeneity analysis reveals that RETI has the strongest impact on CP in the eastern region, followed by the central region, but has a negligible effect in the western region. Among the different types of RETI, the positive effects of solar, wind, and energy storage technology innovations on CP are more evident. Moreover, the impact of RETI on CP is stronger in economically developed provinces than in less developed ones. The mechanism analysis shows that RETI indirectly enhances CP by optimizing industrial structure, increasing renewable energy generation, and improving energy efficiency. The threshold effect analysis suggests that as ER intensifies, the positive effect of RETI on CP follows a non-linear relationship that strengthens initially but then diminishes. In contrast, as RD rises, the marginal benefits of RETI on CP are continually strengthened.