Networked power infrastructure, energy transition, and supply chain resilience: Evidence from China's ultra-high voltage transmission

Large-scale networked energy infrastructure is increasingly recognized as a critical instrument for environmental management, as it shapes the allocation of energy resources, the integration of clean energy, and the stability of production systems under climate and energy transition pressures. Exploiting the staggered commissioning of China's ultra-high voltage (UHV) power transmission projects as a quasi-natural experiment, this study investigates how infrastructure-induced improvements in power supply security affect firm-level supply chain resilience. Using panel data on Chinese A-share listed firms from 2007 to 2023 and a multi-period difference-in-differences approach, we find that UHV deployment significantly enhances supply chain resilience. Mechanism analyses indicate that, at the system level, UHV mitigates supply chain vulnerability by alleviating power shortages, reducing electricity cost pressures, and weakening regionally fragmented energy markets. From an environmental perspective, resilience gains operate through cleaner energy consumption in power-importing regions and higher energy efficiency in power-exporting regions. Further analyses reveal stronger effects in regions with lower electricity dependence, in power-importing areas, and in energy-intensive industries. Overall, the findings underscore the role of networked power infrastructure as an environmental management tool that simultaneously supports low-carbon transition and reduces systemic production risks.