Closed Cycle Power Take Off for OWC Wave Energy Devices

Project Description

Wave power has long been an attractive potential source of renewable energy. Wave power has: the highest energy density among renewable energy sources; high availability; good predictability; and is decorrelated with wind and solar power. This is true in many locations in the world, not just Ireland, so this represents a global market for commercialization. However, wave energy is still in infancy, with a large number of concepts at various stages of development. One class of device is called the oscillating water column (OWC) in which the wave power is transferred to air flow. Two problems have dogged the development: the air flow through the turbine is bidirectional and the turbine experiences a large variation in peak pressures in irregular seas. The Closed Cycle Power Take-Off (CCPTO) is a novel concept that addresses both these problems. However, the sensitivity of the CCPTO to basic geometric sizing (e.g. volume of air accumulators) or the likely performance with realistic turbine characteristics is unknown. Furthermore, the appropriate configuration of the turbine for a CCPTO is undefined. This project will bridge this knowledge gap. This will be achieved by using turbine data obtained from high fidelity computational fluid dynamics simulations coupled conjunction with reduced order models of the device. This will also allow an exploration of possible control strategies that may enhance operation. Thus, the project will advance the CCPTO concept beyond the current low technology readiness level of 1-2 to a TRL of 3 and will provide a design framework for further development.