Parameters affecting scalable underwater compressed air energy storage

Underwater compressed air energy storage (UWCAES) is founded on mature concepts, many of them sourced from underground compressed air energy storage technology. A fundamental difference between the two systems is the way in which air is stored. UWCAES utilizes distensible boundary, submerged air accumulators as opposed to rigid walled caverns. This paper presents an analysis of the primary design parameters in a basic UWCAES system. The results from the parametric study and first-order sensitivity analysis show the importance and impact each design parameter has on overall system performance and can serve as a first reference guideline in system design. The analysis revealed significant system sensitivities to pipe diameter, expander and compressor efficiencies, and air storage depth. The air compression and expansion processes contributed most to system exergy destruction for all parametric study cases.