3 - National Wave Power Programmes

Abstract

This chapter presents the concept of power generation using wave power. A number of potential methods for harnessing and converting wave energy to electric power have been developed. These include the Salter Ducks and the Lochness Trials. The Salter device consists of an oscillating vane that can extract a high percentage of incident wave energy with the shape of its vane. The Nottingham Wave Energy Research Program designs air buoys plus a self-rectifying air-driven turbine for use on each buoy, together with a generator. The air buoys can absorb energy from the waves over a wide range of frequencies. Further studies are being made to improve the aerodynamic efficiency of a range of self-rectifying air turbines based on the Savonius access windmill but modified to operate within a duct. The Indirect-Pneumatic Wave Energy Convertor, built in Egypt, was intended to illustrate the feasibility of the concept and to study system performance and its conversion efficiency at different wave amplitudes. The system makes use of a single-cylinder air compressor, plus a piston, which derives its oscillating motion from a float that rides on the waves. However, there is a lack of symmetry in the movement of the float about the equilibrium position, the upward-compression stroke being shorter than the downward suction stroke.