Research has shown that isentropic efficiency for compressors as well as expanders are key determinants of the overall characteristics and efficiency of compressed air energy storage systems . Compressed air energy storage systems are sub divided into three categories: diabatic CAES systems, adiabatic CAES systems and isothermal CAES systems.
The compressors- one of the key components of compressed air energy storage systems operate using prime movers, such as motors [, ]. These compressors pressurize air as it starts its journey into the storage cavern .
Analysis of compressed air energy storage systems is usually conducted by taking both compression and expansion stages into consideration using ideal gas laws. Expanders’ mechanical work is first transformed.
The number of sites available for compressed air energy storage is higher compared to those of pumped hydro [, ]. Porous rocks and cavern reservoirs are also ideal storage sites for CAES. Gas storage locations are capable of being used as sites for storage of compressed air .
CAES system components In general terms, Compressed air energy storage (CAES) is very similar to pumped hydro in terms of the large-scale applications, as well as the capacity of both in terms of output and storage.
There are several compression and expansion stages: from the charging, to the discharging phases of the storage system. Research has shown that isentropic efficiency for compressors as well as expanders are key determinants of the overall characteristics and efficiency of compressed air energy storage systems .