Wave Energy: An Economic Appraisal

Part of the immense solar energy input to the earth is converted by natural processes into energy associated with ocean waves. The geographical location of the United Kingdom renders it one of the world's most favoured countries with respect to the potential availability of wave energy. In principle, the waves reaching our coastal waters from the North Atlantic might satisfy a considerable fraction of our electricity demand provided that reasonably high overall conversion efficiencies can be achieved. Inventors have recognised the power of the sea for many decades, and there has been no lack of ideas on how it. might be tapped. But none of the ideas was developed on a substantial scale, since ample and relatively cheap supplies of other resources were always available. In recent years, however, there has been a growing recognition that - on a world scale - the presently used forms of energy may become too expensive, too scarce or otherwise unavailable to meet our energy needs by themselves. The Government's responsibility is to ensure that as wide a range as possible of energy supply options are available when they may be needed. Research and development can provide the necessary technical and economic data on which the ultimate choices can be made. Within this context, the Government announced in 1976 the start of an R&D programme on wave energy for which the first phase was to be a feasibility study lasting for two years. The funding level has been increased twice since that time to maintain the momentum of the programme in the light of technical progress. The programme has had three main components: exploratory development of several different engineering concepts of wave energy converter; supporting research in relevant engineering and scientific areas: the collection and analysis of wave data; analysis of the structural response to wave induced motions; mooring; energy conversion and transmission; environmental aspects; working up preliminary reference designs of full scale stations for technical and economic appraisal. The purpose of this paper is to review the present state of knowledge of wave energy in the light of the achievements of the first two-year phase of the programme.