The role of renewable energy investment and energy resource endowment in the evolution of carbon emission efficiency: spatial effect and the mediating effect.

With climate change caused by massive greenhouse gas emissions emerging as an issue of global concern, it is urgent to improve carbon emission efficiency (CEE) for countries along the Belt and Road (BRI). Considering the resource endowment characteristics of green development in BRI countries, the super-efficiency slacks-based measure (SBM) model is adopted to evaluate the current status and tendency of CEE in 60 BRI countries, while the Global Malmquist-Luenberger (GML) index to quantify the spatial and temporal variation and dynamic evolution of CEE. Subsequently, from the perspective of energy development and utilization, the spatial Durbin model (SDM) and the mediating effect model are employed to empirically examine the spillover effects and driving mechanisms of renewable energy investment and energy resource endowment on CEE. Empirical results reveal that (1) from a static perspective, the CEE of BRI countries is generally poor and unevenly distributed in terms of temporal and spatial dimensions, with significant room for enhancement. (2) Referring to the dynamic level, the GML index featured a U-shaped fluctuation, with technological progress contributing to the improvement of CEE. (3) There is a significant positive effect of renewable energy investment on CEE in the home country and neighboring countries, while energy resource endowment presents a remarkable adverse correlation. Consequently, it is suggested that inter-regional cooperation among BRI countries should be strengthened to reinforce renewable energy investment, exert the technology and knowledge spillover effect sufficiently, and break the resource curse in the environmental field. (4) The mediating effect model confirms the significant mediating mechanism of technological innovation. Renewable energy investment can enhance the CEE of BRI members by promoting the positive mediating effect of technological innovation, while energy resource endowment can inhibit the local level of technological innovation and indirectly inhibit the CEE of BRI members. The findings provide new ideas on the green development and ecological sustainability of the energy industry in BRI members and other economies.