A Compressed air energy storage system: steady state performance analysis and design

Energy storage systems are playing a vital role in increasing the renewable energy sources penetration in remote isolated hybrid systems. Energy storage systems are used to meet the peak load demand when the available renewable energy is not sufficient. Compressed Air Energy Storage (CAES) system is one of the possible options which has been selected in this research due to its good characteristics such as high number of operating cycles, short or long term storage ability, high depth of discharge and acceptable discharge time. Both energy storage and extraction procedures are achieved through a thermodynamic compression and expansion of the ambient air. In this paper, the steady state modeling and design of a micro CAES for possible applications in remote hybrid power systems will be presented. Using the system steady state characteristics an optimum operating strategy for the system is determined to achieve maximum energy extraction. Steady state models of the air motor, air storage and the coupled synchronous generator are presented. The designed system is simulated in Matlab/Simulink and its expected steady state characteristics and performance are discussed.