China has operationalized the world's largest compressed air energy storage facility in Jiangsu province, marking a major technical milestone in stabilizing its green energy grid. Developed by Harbin Electric Corporation, the facility uses underground salt caverns to store energy as compressed air for long-duration support.
Harbin Electric Corporation recently announced that the second unit of its salt cavern demonstration project in Jiangsu province has achieved full-load power generation and entered full commercial operation. The facility represents a significant advance in long-duration storage technology, comprising two 300-megawatt non-combustion storage units with a total capacity of 2,400 megawatt-hours and a world-leading 71 percent conversion efficiency.
Once fully integrated into the regional grid, the project is expected to generate about 792 million kilowatt-hours of electricity annually, supplying stable power to roughly 600,000 households. It is projected to reduce standard coal consumption by 250,000 metric tons and cut carbon dioxide emissions by 600,000 tons each year, delivering substantial environmental benefits.
The launch occurs amid explosive growth in China's energy storage sector, which serves as a vital buffer for the country's rapidly expanding intermittent wind and solar installations. Beijing has targeted over 180 gigawatts of new-type energy storage capacity by the end of 2027, spurring innovation in methods like salt cavern compressed air storage and positioning China as a key testing ground for next-generation energy infrastructure.