Cylindrical Composite Structural Design for Underwater Compressed Air Energy Storage

Abstract The utilization of renewable energy sources is pivotal for future energy sustainability. However, the effective utilization of this energy in marine environments necessitates the implementation of energy storage systems to compensate for energy losses induced by intermittent power usage. Underwater compressed air energy storage (UWCAES) is a cost-effective and emission-free method for storing energy underwater. This technology has proven to be effective and viable, and it offers significant benefits in terms of energy efficiency and sustainability. In this paper, a cylindrical composite structure UWCAES tank is designed. At first, the materials and shapes of the different forms of air containers were evaluated, and the relationship between container diameter, length, and number of air containers was analyzed on the basis of the range of energy storage densities for different kinds of systems. Subsequently, the materials to be applied in the tanks were investigated and selected according to the actual working conditions of the system. Eventually, finite element models (FEMs) and prediction formula were developed, and the influence of changes in the thicknesses of the steel reinforcement was discussed. The results demonstrated that the storage tank possesses adequate environmental resistance and load-bearing capacity, which can provide a reference for its practical engineering implementation.