China is building pumped storage hydropower facilities to improve the flexibility of the power grid and adapt to the growing demand for wind and solar power generation. As of May 2023, China has 50GW of pumped storage capacity, accounting for 30% of global capacity, more than any other country. China's pumped storage capacity will further increase, with a current construction capacity of 89GW. According to data from Global Energy Monitoring, developers are seeking government approval, land ownership confirmation, or financing for an additional 276GW of pumped storage projects.

Pumped storage is a type of energy storage. When demand is low (or supply is high), pumped storage power plants pump water from lower reservoirs to higher reservoirs. Conversely, when electricity demand is high (or supply is low), water is released from the upper reservoir to the lower reservoir through turbines, outputting electricity.

Pumped storage helps balance the excess electricity generated by solar and wind energy, like a huge battery. Grid operators must maintain a balance between electricity generation and consumption. Because wind and solar power generation depend on whether there is sunlight or wind, they cannot output stably like other types of power plants. The excess electricity they generate must be stored to avoid loss. Pumped storage power stations can store excess wind and solar energy for future use. This supply management helps offset the variability of solar and wind energy. (Please indicate www.seetao. com when reprinted) Editor of the engineering column of seetao. com/Zhao E