Thermodynamic analysis of a compressed air energy storage system through advanced exergetic analysis

Compressed air energy storage (CAES) is an economic, large-scale energy storage technology, but its further applications are limited by thermodynamic inefficiency. Although high-exergy destruction components can be highlighted through exergy analysis, the interactions among components and the true potential for the improvement of CAES are not obvious. In this study, an advanced exergy analysis was applied to the CAES system. The exergy destruction within each system component was split into four parts, namely, endogenous, exogenous, avoidable, and unavoidable. The thermodynamic properties of CAES were discussed in detail by combining the four parts. Results indicate that the unavoidable part of exergy destruction within the components of the system is larger than the avoidable part. The most important components based on the avoidable exergy destruction are combustion chambers, intercoolers, and aftercoolers. Exergy destruction can be significantly reduced by improving the main component efficiencies. More than half of the avoidable exergy destruction is exogenous, which indicates that interactions among components have a considerable impact on the CAES performance. (C) 2016 Author(s).