Energy storage is a key pillar in the transition towards more sustainable energy systems. Among the available options, the compressed air storage (CAES) is gaining prominence for its ability to integrate renewable energy sources into the grid.
In China, an ambitious CAES project developed in Hubei province It is marking a before and after in this field. Signed by the Huaneng Group, this “air battery” is not only the largest in the world, but also an example of efficiency and technological innovation. The project, completed in April, It has a storage capacity of 300 MW/1500 MWh and a cost of 270 million dollars.
Pilot project: a massive laboratory for innovation
Located in the abandoned Yingcheng Salt Minesthe project was built in just two years, a significantly shorter time compared to pumped hydroelectric systems, which typically take six to eight years.
With a round trip efficiency of 64%, which could be increased up to 70% thanks to future optimizations, this project will contribute to balancing the regional electrical grid during demand peaks and It will facilitate the integration of renewable energies such as solar and wind.
We are talking about a very high round trip efficiency (a term that refers to how much of the stored energy can be recovered after having gone through the storage and recovery process), since a value of 64% means that, for every 100 units of stored energy, 64 useful units can be recovered. The remainder (36%) is lost due to inherent system limitations such as heat dissipation or friction.
Gas storage. Source: Tsimghua University
In parallel to the main project, it was carried out in the same region a 60 MW pilot project promoted by Tsinghua Universitywith technology that promises to revolutionize the sector. This system, designed to eliminate the need for external fuels, reuses the heat generated during air compression, achieving zero carbon emissions and efficiency again greater than 60%.
In addition, it incorporates advances such as high-load centrifugal compressors, advanced heat exchangers and large-scale turbines, all developed and manufactured in China. One of the most notable innovations is its ability to start operations in five minutes, thanks to a ‘one-click’ start system and quick-response pneumatic turbines.
Second phase: towards the future of energy storage
With the success of the pilot, Huaneng Group launched the second phase of the project in Jintan. This will include two additional 350 MW units with a combined storage capacity of 2.8 GWh, which will make it the largest CAES facility in the world.
Designed for 330 annual charge and discharge cycles, the system will not only surpass current technologies in efficiency, but will also set a standard in sustainable energy solutions. The collaboration between Huaneng Group, China Salt Group and Tsinghua University has been key to the success of the project.
Each entity provides unique resources: infrastructure for underground storage, investment and the technological innovations necessary to achieve this ambitious goal. Additionally, the project represents a milestone in the use of salt caverns for energy storage, positioning China as a leader in the sector.
Beyond China: a global technology
Turbine. Source: Tsimghua University
Energy storage using compressed air is attracting interest worldwide. Companies like Toronto-based Hydrostor They are developing projects in Australia and California that could expand the applications of this technology in areas without salt caverns. Although these alternatives are in early stages, they underscore the growing importance of CAES as a complement to traditional batteries.
For now, the Jintan project not only demonstrates the potential of compressed air as a tool to address renewable energy intermittency, but also highlights the ability of technological innovation to advance towards a cleaner energy future. The diversification of storage solutions is crucial to accelerate the transition towards a sustainable electricity grid, and this “air battery” could be the model to follow in the coming years.
Source: www.motorpasion.com
