At the end of May, two pumped-storage power stations with a capacity of a million kilowatts was put into operation in south China's Guangdong Province, one located in Meizhou city, and the other in Yangjiang city. Officials said they would promote clean energy and help ensure steady supplies of electricity.
Pumped storage power station functions like a power bank. When the demand for electricity is low, the station uses excess electricity to pump up water into the upper reservoir and store it. When the demand for electricity is at its peak, stored water is released to generate electricity.
It took just four years to build the Meizhou station, the shortest construction period for this kind of project in China, and the Yangjiang station has the largest single unit capacity of generators in China.
"The Yangjiang Pumped Storage Power Station has three 400,000 KW generating units, the largest single unit capacity in China. When the main spindle of the generator rotates clockwise, it is generating electricity. When it rotates counterclockwise, it is pumping water," said Peng Qian, the Executive Director of Yangjiang Pumped Storage Power Station, which is under CSG (China Southern Power Grid) Power Generation.
During the construction, cost-efficiency was also taken into consideration.
"Our upper reservoir has a total storage capacity of 28 million cubic meters, which allows our three units to generate power for nearly 30 hours at full load. The upper and lower reservoirs are connected by a 3.6-kilometer channel with reinforced concrete lining. We saved nearly $30 million on the construction of the channel alone," added Peng.
Given the storage and monitoring mechanism, pumped storage power station is a clean and useful part of the green energy sector.
"Wind, solar and other green energy generation is highly dependent on natural conditions, and the output is often random and fluctuating. When they're used in the power grid, it becomes significantly more difficult to maintain the balance of the grid. Pumped storage power station can effectively guarantee power balance," said Li Hua, the Deputy General Manager from Strategic Planning Department of CSG Power Generation.
The two new stations significantly increase the consumption capacity of clean energy in the Greater Bay Area (GBA), contributing to a world-class power grid.
"Clean energy currently accounts for nearly 50 percent of all generated electricity in the Greater Bay Area. And more than 95 percent of clean energy that is generated there is actually used. These two figures are among the highest in the world," added Li.
Li said the pumped storage power station can also help ensure stable supplies of electricity to individual households.
Li added that more than half of the cities in the GBA have an average annual blackout time of less than one hour, and these two new stations might help lower this figure even further.