Wave Power
Wave power is the transport of energy by ocean waves, and the capture of that energy to do useful work — for example for electricity generation, water desalination, or the pumping of water (into reservoirs). The worldwide wave power resource potential is huge. And the global power potential has been estimated to be around 8,000-80,000TWh/y (1-10TW), which is the same order of magnitude as world electrical energy consumption. The best wave climates, with annual average power levels between 20-70 kW/m of wave front or higher, are found in the temperate zones (30-60 degrees latitude) where strong storms occur. However, attractive wave climates are also found within +30 degrees latitude where regular trade winds blow, the lower power levels being compensated by the smaller wave power variability.
To this point wave energy has been mostly unused. The foremost reason for this is that earlier construction principles of wave power plants have not been cost efficient. In order to cope with the ocean storms robust converters have been constructed and often highly sophisticated systems have been used. The ocean waves are a very concentrated renewable energy resource that is the reason to harvest it but also the reason that converters brake down during storms. However systems to harvest utility-scale electrical power from ocean waves have recently been gaining momentum as a viable technology. The world’s first commercial wave farm was based in Portugal, at the Aguçadoura Wave Park, which consists of three 750 kilowatt Pelamis device.