Shanghai Electric Supplies Core Equipment for World's Largest Compressed Air Energy Storage Station
Shanghai, China — The Huai’an Salt Cavern Compressed Air Energy Storage (CAES) demonstration project in Jiangsu Province, the world’s largest compressed air energy storage station, has officially begun operation. Shanghai Electric (SEHK:2727, SSE:601727) supplied the core equipment for the project, including air turbine units, generators, electric motors, and liquid salt storage tanks.
Unit 2 connected to the grid and immediately began full-power generation in its first test. This achievement marks an important engineering milestone in supporting the development of new power systems in China.
The project comprises two CAES units with no additional combustion, each with a capacity of 300 MW, for a total installed capacity of 600 MW, energy storage capacity of 2,400 MWh, and a conversion efficiency of around 71%. The air will be compressed and stored in a salt cavern during periods of low electricity demand, then released to drive the turbines and generate electricity as demand rises. The system also helps to stabilise the grid by regulating peak load and frequency.
Using about 980,000 cubic metres of salt cavern at depths of 1,150 to 1,500 metres below ground in Huai’an, the project employs high-temperature adiabatic compression technology without additional combustion, using a “salt liquid + pressurised hot water” system. With this technology, heat from the compression process can be stored and reused throughout the operation cycle without burning fossil fuels, delivering significant reductions in carbon emissions.
The first 300 MW unit began operation in December 2025, followed by Unit 2 more recently. With a total investment of around US$520 million, the facility, now in full operation, is expected to generate about 792 million kWh of electricity per year, enough to meet the needs of around 600,000 households. The project can also save around 250,000 tonnes of standard coal and reduce CO₂ emissions by about 600,000 tonnes per year, thereby making a tangible contribution to the region’s energy transition.
Shanghai Electric Power Generation Group provides a wide range of major equipment for this project, including power generation and thermal storage systems. This broad scope of work demonstrates Shanghai Electric’s integrated engineering capabilities in turbine technology, power generation equipment, and thermal storage systems, while delivering reliable and replicable equipment solutions for long-term energy storage projects worldwide.
As the world moves towards carbon neutrality, long-term energy storage technologies such as CAES are key to enhancing grid resilience while supporting large-scale integration of renewable energy. By leveraging the system integration experience from this project, Shanghai Electric continues to develop high-tech equipment manufacturing and integrated solutions to support the global energy transition and modernisation of power systems.