How does renewable energy technology innovation affect manufacturing carbon intensity in China?

Renewable energy technology innovation (RETI) is a crucial driver for promoting the manufacturing green transformation. However, few studies have explored the impact of RETI on manufacturing carbon intensity (MCI) from the perspective of spatial spillover and regional boundary. Based on the manufacturing panel data of 30 provinces in China from 2006 to 2020, this study examines the mechanism, spatial spillover effects, regional boundaries, and industry heterogeneity of RETI on MCI using the spatial Durbin model. The results show that (1) RETI significantly inhibits local and neighboring MCI. (2) The spatial spillover effect of RETI on MCI has a significant regional boundary, which is inhibitory in the range of 800 km and shows a significant "half-decay" characteristic at 400 km. However, in the range of 800 to 1400 km, RETI significantly promotes neighboring MCI. (3) The inhibitory effect of RETI on MCI has temporal and regional heterogeneity, which gradually increases over time, and the effect from high to low is central, west, and east. (4) RETI has a significant inhibitory effect on MCI of pollution-intensive, high-income, capital-intensive, and labor-intensive manufacturing in local and neighboring areas, but it has a more negligible effect on non-pollution-intensive, low-income, and technology-intensive MCI. The findings provide empirical evidence for formulating targeted and differentiated policy in manufacturing low-carbon development.