Calculate the air flow, compressed air temperature, and storage volume for a 1500 MWh output CAES unit charging for 7.5 hrs. Assume compressor inlet at 1 bar, 20°C, and compressor exit at 100 bar. Assume the compressor and peaking turbine efficiencies to be 70% and 60% respectively. Take γ = 1.4, Cp = 1.005 kJ/kg-K, and R = 0.287 kJ/kg-K for air.
What is the air in kg/s? Neglect sensible heating of PCM and assume specific heat of air to be 1.0 kJ/kg-K.