Patent ID: 7669423

Claim:
A method of reducing a volume of an air storage of a compressed air energy storage (CAES) power generation system having a combustion turbine assembly including a main compressor constructed and arranged to receive ambient inlet air, a main expansion turbine operatively associated with the main compressor, at least one combustor constructed and arranged to receive and preheat compressed air from the main compressor and to feed the main expansion turbine, and an electric generator associated with the main expansion turbine for generating electric power, the method including: releasing compressed air from an air storage, humidifying the compressed air released from the air storage, heating the humidified compressed air using exhaust heat from the combustion turbine assembly, expanding the heated, humidified compressed air in an air expander that is separate from the combustion turbine assembly, the air expander being constructed and arranged to permit a portion of airflow expanded by the air expander to be extracted and injected, under certain conditions, into the combustion turbine assembly for power augmentation, and generating, via an electric generator that is separate from the generator of the combustion turbine assembly, additional electric power using air expanded through the air expander, wherein humidifying the compressed air enables a volume of compressed air stored in the air storage to be reduced as compared to a volume thereof absent the humidifying step.