The world’s largest station for electricity storage in flow batteries

On September 29, 2022, the station with the largest capacity and power in the world dedicated to storing electrical energy in flow batteries was connected to the electricity grid. It will be in the testing phase for a few days and will start operating in mid-October. With 100 megawatts, the Dalian station in China will be able to accumulate large amounts of energy when there is a surplus of it, and supply it to the electricity grid when there are peaks in demand.

The construction of this station was approved by the China National Energy Administration in April 2016.

The technical success of this ambitious project is largely due to the team led by Xianfeng Li, from the Dalian Institute of Chemical Physics (DICP), under the Chinese Academy of Sciences. The system was built by the Chinese company Rongke Power Co. Ltd.

Based on the typical personal electricity consumption in China, which is 2 kWh per capita, the new station can meet the daily electricity demand of 200,000 residents, thus reducing the pressure on the electricity supply during periods of peak demand and improving the reliability of power supply in the southern sector of Dalian.

Energy storage technology is also particularly important to facilitate the use of renewable energies, which are not always accessible due to variations in wind, sunlight and other comparable natural sources.

The Dalian power station uses a flow battery electrical energy storage system developed by the Dalian Institute of Chemical Physics and based on vanadium.

A sector of the facilities within what has become the world’s largest station for electricity storage in flow batteries. (Photo: DICP)

The station will serve as an “electricity bank” and will equalize the energy of the electrical network, saving it when it is on the network and contributing it when it is scarce, which will be of great help to make extensive use of renewable energies in the area, essentially solar and wind.

These renewable energy sources will be used to recharge the station’s batteries during periods of low demand, converting electrical energy into chemical energy stored in the batteries. When peaks in demand occur, the stored chemical energy will be converted back into electrical energy and supplied to users.

The station’s energy storage technology uses vanadium ions of various valence states. The conversion to electrical energy and the conversion to chemical energy are carried out through redox reactions of these ions in the positive and negative electrolytes, thus realizing large-scale storage and release of electrical energy. (Font: NCYT by Amazings)