Wave power is the term used to describe the harnessing of the energy contained in the ocean’s surface waves, and converting that energy into a useful form – usually electricity generation. Wave energy is essentially stored, concentrated wind energy, the waves being created by the progressive transfer of energy from the wind as it blows over the surface of the water, making wave power a renewable energy source and although it is often grouped together with tidal power and ocean currents, it is a separate and distinct energy source.
Although wave power generation is not a widely employed commercial technology at the moment, there have been many attempts at using it since at least 1890. Even though waves are a powerful source of energy, it is not easy to harness this energy and convert it into electricity in large amounts. Thus, wave power stations are rare.
A company called Pelamis Wave Power Ltd developed a method of offshore wave energy collection, using a floating tube called “Pelamis”. This long, hinged tube (about the size of 5 railway carriages) bobs up and down in the waves, as the hinges bend they pump hydraulic fluid which drives generators.
The world’s first commercial wave farm is based in Portugal, at the Aguçadora Wave Park and consists of three 750 kilowatt Pelamis devices.