On July 20, 2026, the cumulative on grid electricity of Zhejiang Tiantai Pumped Storage Power Station exceeded 1 billion kilowatt hours. At this time, it has only been 7 months since the first unit was connected to the grid in December 2025. This pumped storage power station, which has created the world's highest rated water head and the record for the largest single unit capacity in China, is providing flexible regulation for the Zhejiang power grid day after day by repeatedly pumping and generating at full load.

447 power generation and 518 pumping operations

The power station is located in Tiantai County, Taizhou, Zhejiang Province, and is invested and constructed by Three Gorges Group. It is a key implementation project of the 14th Five Year Plan in China. The total installed capacity of the power station is 1.7 million kilowatts, with a total of 4 pumped storage units installed with a single capacity of 425000 kilowatts. It is currently the largest pumped storage power station in China with a single capacity. The rated head of the power station is 724 meters, which is the highest among similar projects in the world; The single-stage diversion inclined shaft is 483 meters long, also setting a domestic engineering record.

Since the first unit was put into operation until July 20th, the power station has accumulated approximately 2383 hours of power generation and 2880 hours of pumping operation, with 447 and 518 power generation and pumping cycles respectively. More noteworthy is that the success rate of one-time start-up of the unit has reached 100%. This means that after receiving the power grid dispatch instructions, the unit can quickly respond and stabilize its output every time.

Complete approval to full capacity production within a five-year plan

The pace of power station construction is equally efficient. Approved in December 2021, the main project will commence in May 2022, the first two units will be connected to the grid for power generation in December 2025, the third unit will be put into operation in April 2026, and the fourth unit will complete trial operation on June 25, achieving full capacity production.

This means that from approval to full operation, the Tiantai Pumped Storage Power Station only took about four and a half years. After the power station is fully put into operation, the average annual power generation is about 1.7 billion kilowatt hours, which is equivalent to saving about 520000 tons of standard coal and reducing 1.04 million tons of carbon dioxide emissions annually. Keywords: energy storage power station, pumped storage

The power station mainly undertakes tasks such as peak shaving, valley filling, frequency regulation, phase modulation, energy storage, and emergency backup for the Zhejiang power grid. On July 1st, Changjiang Power officially took over the operation of the power station at full capacity. One billion electricity is just a node, the true value of a power station lies in its precise response to dispatch instructions time and time again, providing stable and flexible support for the power grid.Editor/Cheng Liting