Investigation of synergistic integration and optimization in combining compressed-air energy storage and a gas turbine

Abstract

It is very important to guarantee performance synergy when combining two sub-systems. This study investigated combinations of compressed air energy storage systems (CAESs) and a gas turbine (GT) while considering various design factors. These factors included the CAES type, CAES capacity, and air injection flow rate, which were not considered in previous studies. The feasibility of various integration scenarios was evaluated, and the best scenario with the highest synergistic effect was obtained through an optimization method. When using a conventional CAES (C-CAES), the combined system was undesirable. When using an adiabatic CAES (A-CAES) or regenerative A-CAES, the combined system outperformed the standalone operation. When the flow ratio of the GT and A-CAES was 1:1.33, the percentage increases in net power and generated energy were 31.5 % and 12.6 %, respectively, and the roundtrip efficiency increased by 3.4 %p. When the flow ratio of GT and regenerative A-CAES was 1:0.88, the percentage increases in net power and generated energy were 31.3 % and 20.6 %, respectively, and the roundtrip efficiency was improved by 2.2 %p. This study provides the best synergistic integration between a CAES and GT for the first time by fully considering various scenarios, including thermal and mass integrations.