Evaluating a new concept for integrating compressed air energy storage in Spar-type floating offshore wind turbines

Abstract

This paper presents a new concept for integrating compressed air energy storage into spar-type floating wind turbine platforms. A preliminary investigation of the implications of integrating the proposed concept on the design and dynamic characteristics of a 5 MW floating offshore wind turbine (FOWT) system is presented. A parametric analysis is undertaken to establish the relationship between the energy storage capacity, the spar geometry and the additional mass of the floating configuration to support high air pressures. Numerical simulations for the dynamic response are performed using the marine engineering software tool ANSYS Aqwa©. The results are compared to those derived for a conventional FOWT-spar configuration without an energy storage system. It is shown that it is technically feasible to integrate energy storage capacities on the order of Megawatt-hours. The increase in spar mass required to cater for compressed air energy storage may be significant. However, this reduces the motion experienced by FOWT structure induced by wind and wave loads.