Workers on Thursday broke ground on what is set to be the world's highest-altitude pumped-storage power station in southwest China's Sichuan Province.

With an altitude of 4,300 meters, the facility is located in Daofu County in the Tibetan Autonomous Prefecture of Garze, according to the Yalong River Hydropower Development Company, Ltd.

Upon completion, the Daofu pumped-storage power station will feature a total designed installed capacity of 2.1 million kilowatts, generating over 2.99 billion kilowatt-hours of electricity annually.

With an expected investment of 15.1 billion yuan (2.11 billion U.S. dollars), it is expected to be the pumped-storage power project with the largest installed capacity in Sichuan, and the world's highest-altitude mega pumped-storage power station, the company said.

Pumped-storage power stations use off-peak electricity to pump water to higher locations, where it is stored and then released to generate electricity when the power supply is strained. They can complement wind and solar power generation, which brings bigger fluctuations to the grid.

The Daofu pumped-storage station is expected to store 12.6 million kilowatt-hours of electricity daily, meeting the power consumption needs of approximately 2 million households in Sichuan.

The station will be of great significance for optimizing the power structure and boosting the complementary development of new energy sources.

At present, the highest-altitude pumped-storage power station in the world is the Yamzho Yumco Lake pumped-storage power station in southwest China's Xizang Autonomous Region, situated at an altitude of about 3,600 meters.