Delingha pumped-storage hydropower station Photo: Screenshot from web

China has started construction of the Delingha pumped-storage hydropower station in Northwest China's Qinghai Province - the highest-altitude pumped-storage power station in Northwest China, according to the State-owned Assets Supervision and Administration Commission of the State Council (SASAC).

Located in Xuji township, the project has a total installed capacity of 600 megawatts. The normal water storage level of its upper reservoir sits at an altitude of 4,008 meters, the SASAC said in a statement on its WeChat account.

With a total investment of 5.23 billion yuan ($783 million), the station will mainly comprise upper and lower reservoirs, a water conveyance system and an underground powerhouse. It is designed to generate 1.2 billion kilowatt-hours (kWh) of electricity annually and consume 1.6 billion kWh for pumping each year, with full operation expected in 2034.

A pumped-storage plant is a green energy storage facility that supports flexible grid regulation. During off-peak hours, surplus power is used to pump water from the lower reservoir to the upper reservoir, storing electricity as gravitational potential energy; during peak demand, the stored water is released to generate power. It performs key grid functions including peak shaving, frequency and phase regulation, and emergency reserve.

Listed as a key project under the 14th Five-Year Plan (2021-25) in the National Energy Administration's Medium- and Long-Term Development Plan for Pumped Storage (2021-35), the Delingha station will shore up grid regulation for the city's 10-gigawatt clean-energy base and fill the gap in large-capacity energy storage in the region.

Sun Chuanwang, a professor at the School of Economics at Xiamen University, told the Global Times on Tuesday that the pumped-storage hydropower station, which is close to the massive clean energy base in the city, will greatly facilitate efforts in conserving and utilizing the clean energy.

With an altitude of 4,300 meters, the Daofu pumped-storage power station in Daofu County, Southwest China's Sichuan Province, is set to be the world's highest-altitude pumped-storage power station, according to the Xinhua News Agency.

Qinghai's Delingha is home to extensive new-energy infrastructure, including solar power generation installations, green hydrogen production facilities, heat-absorbing towers and energy storage facilities.

By 2026, Delingha had a total installed clean energy capacity of 6.05 million kW, with another 950,000 kW under construction, according to city authorities. The city is striving to see its clean energy installed capacity breaking 14 million kW by 2030.