Regional economic and environmental effects of ultra-high-voltage: Evidence from ultra-high-voltage transmission projects in China

Ultra-high-voltage transmission projects are increasingly recognized for their role in sustainable development. This study investigates the economic and environmental impacts of ultra-high voltage (UHV) projects. Our findings show that UHV significantly enhances economic activities and reduces CO 2 emissions, with a significant positive effect on air quality. Heterogeneity analysis reveals different impacts depending on the transmission type, while mechanism tests highlight the pathways of influence. UHV also reduces market fragmentation and fosters regional integration, demonstrating synergies between economic growth and environmental sustainability. These findings provide valuable insights for policymakers aiming to balance economic growth with environmental protection. • Ultra-high voltage (UHV) transmission enhances economic activities and reduces CO 2 emissions. • UHV projects significantly improve regional air quality and environmental sustainability. • Heterogeneity analysis reveals varying regional impacts based on transmission type. • UHV fosters regional integration by reducing market fragmentation. • Findings provide policy insights for balancing economic growth and environmental protection.