“Management strategies for a compressed air energy storage plant”

Energy storage can balance supply and demand over different time scales, with technical and economical benefits. In the present paper, commercial gas turbines, just modified for storage purposes, are considered. The possibility to improve their profitability in an utility perspective is investigated. The adopted strategy is based on a fair mix of different working states (charging, discharging, stand by or mere Brayton cycle operation), according to the instant energy market price, the previous history (storage level) and the plant features (reservoir and GT size). A simple mathematical model of the plant was conceived and a dynamic self-adjusting abacus was developed in order to select a suitable sequence of working ways. The expected results consist in the improvement of the daily cash flow and in the peak power augmentation. Both of them are due to the chance of exploiting a turbo expander not loaded with the compressor driving during the hours when energy price is the highest.