Construction of a large pumped-storage hydropower project started on Thursday in Ganzi Tibetan Autonomous Prefecture, southwest China's Sichuan Province.

At an altitude of 3,000 meters, the Yalong River Lianghekou pumped-storage hydropower plant is believed to be the highest-altitude one of its kind in China.

The project depends on two reservoirs, the Lianghekou hydropower plant upstream and the Yagen hydropower station downstream, and will install four 300,000 kW reversible units.

The total installed capacity of the project is designed to reach 4.2 million kW, including the 3 million kW of Lianghekou hydropower station.

The project is expected to improve efficiency of electricity supply in Sichuan Province, optimize grid network, and promote green and low-carbon development.