Energy analysis of wave and tidal power

Energy requirements for building wave and tidal-power systems have been estimated. For wave-power systems, the relationship between energy requirements and extraction efficiency is examined. It is found that a point of maximum net output is reached, beyond which further increases in extraction efficiency result in decreased net energy. Energy analysis thus identifies a limit on the energy which could, in principle, be extracted by a wave-energy system. Although similar limits could be identified for other types of energy source, the tidal-power analysis is confined to a brief comparison of energy inputs and outputs.