Abstract
Global demand for energy increases annually, at the same time as the demand for carbon-free, sulphur-free and NOx-free energy resources grows considerably. This is manifested in the research for newer sources like biomass and shale gas as well as the renewable energy resources like solar, wind, geothermal and hydraulic energy.
Wave energy is also a form of renewable energy which has not fully been exploited technically and economically. However, it is beyond doubt that the demand for wave energy will soon increase as fossil energy resources are depleted and environmental concerns gain more importance.
The electrical energy to be supplied to the grid shall be produced from the wave energy whose conversion can basically be carried out by three classes of systems:
- Systems that exploit the motions or shape deformations of their mechanisms involved, being driven by the energy of waves passing.
- Systems that exploit the weight of the seawater stored in a reservoir or the changes of water pressure by the oscillations of wave height,
- Systems that convert the wave motions into air flow.
This study is aimed for a general survey of the systems and classification of the wave energy converters based on their types and functionality, as well as investigating their state-of-the-art.