Thermodynamic Modeling of Air Reservoir for CAES Power Plant

CAES (Compressed Air Energy Storage) is an energy storage method which preserves electric energy in the form of air pressure potential energy. As the storage space, the internal air pressure of air reservoir significantly affects the performance of the CAES system. Based on a thorough study of variable pressure air reservoir of CAES, this paper puts forward a thermodynamic modeling method which could be perfectly applied in air pressure and temperature variation analysis. Modeling parameters are fitted by serving Huntorf power plant in Germany as reference case; results show that the obtained pressure curves match the actual curves, which in turn demonstrate the high accuracy of the model presented. By comparing different pressures under several working conditions, it is clear that alternately air releasing and air inflation effectively reduce throttling loss and the energy consumption of compressor, also system efficiency is improved.