Beijing, 27 January 2026 – China has started up what is being touted as the world’s largest compressed-air energy storage (CAES) power plant, a major milestone in long-duration energy storage technology that supports renewable generation and grid stability amid expanding clean power deployment.
The facility, part of China’s rapid expansion of next-generation energy storage systems, boasts 2,400 megawatt-hours (MWh) of storage capacity and can generate up to 600 megawatts (MW) of power, enough to meet the annual electricity needs of roughly 600,000 households.
How Compressed-Air Energy Storage Works
Compressed-air energy storage functions by pressurising air using surplus electricity, storing it in large underground reservoirs or caverns, and then releasing the pressurised air through turbines to generate electricity when demand rises. This allows the system to act as a buffer between intermittent renewable supply and peak grid demand, helping to balance variable inputs from solar and wind.
CAES systems like this one provide long-duration storage that complements traditional battery technologies. Unlike lithium-ion batteries, which are widely used for shorter-term storage, CAES can hold and dispatch large amounts of electricity over extended periods, improving grid flexibility and reducing reliance on fossil fuel-based “peaker” plants.
Strategic Role in China’s Energy Transition
China has been aggressively scaling up renewable energy capacity, particularly wind and solar, requiring large storage systems to maintain grid reliability and energy security. Experts say compressed-air storage plays an increasingly important role as the share of renewables rises, enabling grid operators to manage supply-demand imbalances more effectively and support decarbonisation goals.
This latest CAES deployment builds on earlier projects in the country that utilised underground salt caverns to store compressed air, a design that maximises storage volume and efficiency. Similar facilities have previously been connected to the grid with capacities of 300 MW and 1,500 MWh, setting world records for the technology’s scale before this new, larger plant came online.
Benefits and Broader Implications
Grid-scale energy storage, including CAES, pumped hydro and advanced battery systems, is widely viewed as essential for integrating large amounts of clean energy while maintaining reliability. Long-duration storage helps avoid curtailment of renewable generation, supports peak demand periods, and can reduce the need for backup fossil fuel generation.
By bringing the world’s largest compressed-air energy storage plant online, China reinforces its leadership in energy infrastructure innovation and contributes to global efforts to decarbonise power systems. As other countries explore similar technologies, this plant may serve as a benchmark in the broader transition toward more resilient and sustainable energy networks.
