File Photo. An aerial view of State Grid Xinyuan Jiangsu Jurong Pumped Storage Power Station in East China's Jiangsu Province.

The world's highest dam-body pumped storage power station — State Grid Xinyuan Jiangsu Jurong Pumped Storage Power Station was put into operation on Tuesday in East China's Jiangsu Province, marking a major milestone in the country's green energy transition, the Xinhua News Agency reported.

The mega project — also described as a large-scale clean energy "regulator" in the Yangtze River delta region, is estimated to generate 1.35 billion kilowatt-hours of green electricity annually after full operation, with a total installed capacity of 1.35 million kilowatts, said the Xinhua report.

A pumped-storage power station is a large-scale energy storage system that helps balance electricity supply and demand. It functions like a giant rechargeable battery -- during off-peak hours, surplus electricity is used to pump water from a lower reservoir to an upper reservoir; when demand increases, the stored water is released through turbines, generating electricity once again.

Standing182.3 meters high,  equivalent to the height of a 60-story building --the tallest of its kind in the world, the power station is capable of storing 17.07 million cubic meters of water, which is equivalent to the water storage capacity 1.2 times the capacity of West Lake in Hangzhou city.

The project has set multiple industry records and serves as a model for the construction of pumped storage power stations in China's high-load plains, CCTV News reported in March.  

According to the operator, the power station uses the elevation gap between the upper and lower reservoirs to pump water from the lower reservoir to the upper reservoir when power consumption is low, converting it into stored energy. During peak hours, the stored water generates electricity that is transmitted to the grid. It is often referred to as a "water energy power bank."

"The project has achieved technological breakthroughs in the development of anti-seepage geomembranes and the installation of super-large ball valves, providing a reference for the construction of pumped storage power stations in high-load plain areas in China," said Chen Hongchun, chairman of State Grid Xinyuan Jiangsu Jurong Pumped Storage Co.

As one of China's most economically developed provinces, Jiangsu's maximum electricity load has exceeded 100 million kilowatts for nine consecutive years, people.com.cn reported.

The electricity load on Jiangsu's power grid hit record highs this summer, with the maximum load reaching 156 million kilowatts, a year-on-year increase of 6.12 percent compared to last year, Xinhua reported.

As a core renewable energy storage technology, pumped storage plays a vital role in advancing the country's green energy transition, according to Xinhua.

Once fully operational, the power station will provide around 2.7 million kilowatts of bidirectional power regulation capacity, said the Xinhua report. It will help alleviate the pressure on the power grid during peak load periods and improve the absorption of new energy sources, said Wang Chenhui, head of the Development Department of State Grid Zhenjiang Power Supply Company.

Located in the high-load center of the East China power grid, the power station will perform multiple functions, including peak shaving, frequency regulation, phase control, and energy storage, to stabilize the power grid, Wang said.

Since the start of the 14th Five-Year Plan period (2021-25), China has added more than 44.53 million kilowatts of pumped-storage installed capacity, with 78 pumped storage units being put into operation by State Grid Corporation of China.

Global Times