Milestone in Jiangsu
On Thursday, November 27, 2025, the Huaneng Jintan Salt Cavern Compressed Air Energy Storage (CAES) Phase II project – set to be the world’s largest CAES facility – completed the hoisting of its core turbine unit in Jiangsu Province on the Chinese mainland, marking the start of main equipment installation.
How CAES Powers the Grid
The turbine, known as the heart of a CAES plant, can respond to grid peak-shaving demands within minutes, ramping from startup to full load in about 10 minutes. It converts the potential energy of expanded air into electricity, enabling quick and efficient balancing of supply and demand.
All core components are 100 percent domestically produced, making this the most powerful turbine of its kind on the Chinese mainland, with the highest single-unit output and largest air intake capacity in the country.
Phase II and Environmental Benefits
Phase II will deploy two 350-megawatt non-combustion CAES units. Chen Hui, deputy director of the engineering, safety and quality department of the project, says that once fully operational, the system will deliver around 330 charge-discharge cycles per year. Each cycle can store up to 2.8 million kWh of electricity—enough to power 100,000 new-energy vehicles.
By shifting peak loads and enhancing grid flexibility, the plant is estimated to save roughly 270,000 tonnes of standard coal and reduce carbon dioxide emissions by about 520,000 tonnes annually. As regions worldwide push for higher renewable integration, this CAES plant could serve as a blueprint for large-scale, non-combustion energy storage solutions.
Global Implications
For entrepreneurs, tech enthusiasts, and policy makers tracking the future of energy storage, Huaneng's CAES milestone underscores a broader shift toward scalable, low-carbon grid solutions. With Phase II’s turbine now in place, the project is on track to reinforce grid resilience and accelerate decarbonization, showcasing how innovation and scale can drive real-world impact.
Reference(s):
Core of world's largest compressed air energy storage plant installed
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