500KW compressed air energy storage in Aarhus Denmark covers an area of

1. Introduction Compressed Air Energy Storage (CAES) has emerged as one of the most promising large-scale energy storage technologies for balancing electricity supply and demand in modern power grids. Renewable energy sources such as wind and solar power, despite their many benefits, are inherently intermittent.

New compressed air energy storage concept improves the profitability of existing simple cycle, combined cycle, wind energy, and landfill gas power plants. In: Proceedings of ASME Turbo Expo 2004: Power for Land, Sea, and Air; 2004 Jun 14–17; Vienna, Austria. ASME; 2004. p. 103–10. F. He, Y. Xu, X. Zhang, C. Liu, H. Chen

2. Storage: The compressed air is stored, typically in large underground caverns such as salt domes, abandoned mines, or depleted natural gas reservoirs. Above-ground alternatives include high-pressure tanks or specially designed vessels, though these are generally more expensive and limited in capacity.

The “Energy Storage Grand Challenge” prepared by the United States Department of Energy (DOE) reports that among all energy storage technologies, compressed air energy storage (CAES) offers the lowest total installed cost for large-scale application (over 100 MW and 4 h).

The high-pressure and high-temperature air is cooled before being stored in an air reservoir. The thermal energy can be dissipated into the atmosphere, stored in TES, or used for heating applications. In the discharging process, stored high-pressure air is released whenever the electricity is required.

T. Zhang, X. She, Z. You, Y. Zhao, H. Fan, Y. Ding Sciacovelli A, Smith D, Navarro H, Li Y, Ding Y. Liquid air energy storage—operation and performance of the first pilot plant in the world.