The China Huadian Xinjiang Mulei Compressed Carbon Dioxide Energy Storage Project, China's first 100-megawatt-class project, has completed its initial grid connection.

The system uses CO₂ as a closed-loop working fluid and incorporates pioneering gas-liquid conversion CO₂ energy storage technology developed by Professor Xie Yonghui's team from the School of Energy and Power Engineering at Xi'an Jiaotong University (XJTU), with Professor Xie as the first inventor.

The project integrated all stages of the CO₂ compression-liquefaction-storage-gasification-expansion-release-generation process, marking another breakthrough in China's key technologies and engineering integration for thermo-mass energy storage, while charting a new path for long-duration energy storage.

Depending on grid demand, during off-peak hours, the project uses surplus electricity to compress room-temperature, ambient-pressure CO₂ while storing the generated heat, then condenses it into liquid CO₂ for storage.

During peak hours, stored liquid CO₂ is gasified by evaporators, and the captured heat is used to convert the high-pressure liquid into a high-temperature gas to drive turbines for power generation.

Once fully operational, the project will generate about 200 million kilowatt-hours of electricity annually, save 50,000 metric tons of standard coal, and reduce CO₂ emissions by about 170,000 tons each year.

It will enhance the grid's peak-shaving, valley-filling, frequency regulation, and voltage regulation capabilities, boosting the power system's flexibility and security while expanding the supply of green electricity.