China’s largest grid developer, State Grid Corporation of China (SGCC), has made progress on its 1,000 kV Sichuan–Chongqing ultra-high voltage alternative current (UHV AC) power transmission project.
It is the country’s highest-altitude UHV AC project and the first UHV AC project in Southwest China. In a key milestone, SGCC successfully installed power lines across Zheduo Mountain, Sichuan, which stands at an altitude of over 4,500 metres. The project entails the construction of 658 km of 1,000 kV D/C lines between Sichuan province and Chongqing municipality (southwestern China) and four UHV substations in Sichuan Ganzi, Tianfu South, Chengdu East and Chongqing Tongliang with a total transformer capacity of 24 GW. The project entails a cost of about CNY29 billion. SGCC officially began its construction in September 2022. Once fully operational by 2025, the project aims to elevate the voltage level of Southwest China’s main power grid from 500 kV to 1,000 kV, enabling the transmission of more than 35 TWh of clean electricity annually.