Wave Energy Conversion With an Oscillating Water Column on a Fixed Offshore Platform

Abstract

The purpose of this study is to examine the feasibility of practical wave energy conversion using an oscillating water column (OWC) and a counter-rotating turbine on a fixed offshore platform. A linear array of such platforms along a coastline, with the power transmitted ashore by submarine cable, constitutes the type of wave energy powerplant discussed herein. The OWC concept utilizes the energy in a wave field to cause the sea, trapped within a cavity in a fixed or floating housing, to oscillate vertically within the cavity, thereby alternately pushing and pulling the air in the cavity through a turbine mounted at an opening in the cavity, thus converting wave energy to usable power. The design, maintenance, and economic aspects of the wave energy powerplant described in the foregoing are discussed for siting around England and Scotland. Gravity, piled, and caisson platform designs are considered in light of current offshore petroleum industry practices and capabilities. Wave energy researchers have made little effort to use proven offshore fixed structure technology, developed by the offshore petroleum industry, in studying ways to house a wave energy conversion device. Such a combination was suggested by McCormick in 1974 and is the subject of this study.