Successfully Connected to the Grid: Broadwell Supports the World’s First 100 MW-Scale Compressed CO₂ Energy Storage Project

On September 30, the world’s first 100 MW-scale compressed carbon dioxide (CO₂) energy storage project—the China Huadian Compressed CO₂ Energy Storage Project in Mulei, Xinjiang—was successfully connected to the grid. As a participant in this major energy storage development, Broadwell Air Dome constructed five gas storage units, providing air dome solutions to support the deployment of this emerging long-duration energy storage technology.

With a rated power of 100 MW and an energy storage capacity of 1 GWh, the project comprises five gas storage units, 141 liquid storage units, and 97 thermal storage units. The system uses CO₂ as its working fluid in a closed loop, storing and releasing electrical energy through transitions between gas and liquid phases. This enables flexible operation in response to grid demand. Each year, the project can absorb approximately 290 million kWh of electricity during off-peak periods and deliver approximately 180 million kWh during peak periods. It can also generate electricity continuously for more than six hours.

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Unlike conventional energy storage methods, compressed CO₂ energy storage cycles through compression, liquefaction, storage, vaporization, and expansion to generate electricity. During charging, the system uses off-peak electricity to compress CO₂, while recovering and storing the heat produced during compression. During discharge, the stored heat is used to convert the CO₂ into a high-temperature, high-pressure gas that drives a turbine to generate electricity. The technology does not depend on underground caverns or other specific geological conditions. Offering high efficiency, low costs, a high level of safety, and pollution-free operation, it provides a new technological pathway for large-scale, long-duration energy storage.

The five gas storage units constructed by Broadwell Air Dome are integral to the overall system. Drawing on its proprietary technology, Broadwell provided gas storage solutions designed to meet the project’s requirements for gas-tightness, structural stability, and long-term operational reliability.

Broadwell’s participation in the world’s first 100 MW-scale compressed CO₂ energy storage project marks an important step in extending its air dome technology beyond established applications in sports and industry into the emerging energy sector. In support of China’s carbon peaking and carbon neutrality goals, as well as the development of a new power system, Broadwell Air Dome will continue exploring applications for air dome technology in energy storage and green energy. Through practical project delivery, the company aims to advance technological innovation and contribute to a clean, low-carbon, safe, and efficient energy system.