Nairobi Compressed Air Energy Storage Project

Among the different ES technologies, compressed air energy storage (CAES) can store tens to hundreds of MW of power capacity for long-term applications and utility-scale. The increasing need for large-scale ES has led to the rising interest and development of CAES projects.

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

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).

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.

CAES systems are categorized into large-scale compressed air ES systems and small-scale CAES. Large-scale systems are capable of producing >100 MW, while the small-scale systems only produce 10 MW or less . Moreover, the reservoirs for large-scale CAES are underground geological formations such as salt formations, host rocks and porous media.

When charged using renewable energy sources, adiabatic CAES can be virtually emission-free. Unlike pumped hydro storage, which can require large reservoirs and potentially disrupt local ecosystems, CAES primarily uses underground geological formations, limiting surface land footprint.