Levelized Cost of Storage Method Applied to Compressed Air Energy Storage

This paper presents a method to calculate the levelized cost of storage (LCOS) dependent on the annual energy output. To allow comparing different storage technologies independently from costs for electricity supply, these costs are fixed at 0 €/kWh. This allows a pure technology comparison and thus the LCOS serves as a first indicator for potentially profitable operation modes of different storage technologies. The method is applied to diabatic Compressed Air Energy Storage (dCAES) and adiabatic Compressed Air Energy Storage (aCAES) with a storage capacity of 1 GWh, a charging duration of 10 h and discharging duration of 6 h. The results show that mean LCOS values decrease strongly with increasing cycling of the storage. With a monthly cycling of the storage system (meaning that the energy storage is completely charged and discharged once a month) the LCOS are 0.36 €/kWh for dCAES and 0.60 €/kWh for aCAES. With a higher utilization the LCOS of aCAES are lower than the LCOS of dCAES. At daily cycling both technologies have an LCOS of about 0.10 €/kWh.