COER are one of the consortium members of LiftWEC, a European research project funded by the Horizon 2020 Programme. The project will develop a novel type of Wave Energy Converter, called the LiftWEC, which uses hydrodynamic lift forces to extract wave energy using a rotating hydrofoil.
Although significant effort has been spent in the last 50 years in searching for a commercially-viable technology for extraction of energy from ocean waves, this objective remains unfulfilled. Although a vast number of different concepts have been proposed and investigated, 99% of these concepts have been based on interacting with the waves using either buoyancy or diffraction forces.
The LiftWEC concept is different because it is based on the exploitation of lift forces generated by wave-induced water velocities. By interacting with lift forces the LiftWEC concept has the advantage that the motion can be unidirectional. In addition, the lift-force can easily be reduced so that the concept can survive storms in the same way that modern wind turbines survive, by stopping turning.
COER, specifically Dr. Andrei Ermakov, will be working on control strategy withing this project. The LiftWEC presents some features common to both wind turbines (unidirectional rotation) and more classical wave energy devices (harmonic excitation). These features combine to present a somewhat unique control problem, with the overall control objective being to minimise the Levelised Cost of Energy (LCoE). In many wave energy control studies, the control objective is simplified to that of energy maximisation. However, this may come with an unacceptable increase in maintenance requirements, due to the increased duty cycle of components, or increased stress on key system components, as the control system seeks to extract maximum power.