On September 12th, Huaneng Jintan 2×350MW Salt Cavern Compressed Air Energy Storage Power Generation Project, the world’s largest salt cavern compressed air energy storage project, completed the full start-up of two main units of its Phase II Project. The stable and reliable operation of two units marks a significant breakthrough in China’s key core technologies and system integration capabilities in the field of large-capacity salt cavern compressed air energy storage.

The Phase II Project is constructed and operated by Huaneng Jiangsu Branch, with a total installed capacity of 700MW and a designed energy storage duration of 8 hours. Under actual air storage conditions, the start-up leverages naturally-formed salt cavern one kilometer underground and reuses the salt cavern cavity built for Phase I as test facilities to verify the coordinated performance of compressors, expanders, heat storage and heat exchange systems, as well as control systems. During the start-up, key parameters including unit vibration, temperature and pressure all outperform design values, fully validating the operational performance of the entire salt cavern energy storage system. Next, the project will carry out pre-grid-connection tests and system integration tests.

After its completion, the project will store surplus renewable power during off-peak hours and deliver stable power output at peak demand periods. Equipped with efficient peak-shaving and fast response capabilities, it will significantly boost the consumption of renewable energy in the Yangtze River Delta region, ensure safe and stable operation of the power grid, and offer important support for the development of China’s new power system and energy security.