My favourite place in the world is by the sea. I can sit for hours watching the rhythmic calm of the sea which I find to be meditative and energising. Perhaps this is what engineering pioneer, Frenchman Girard and his son also reflected on in 1799 when they developed the first wave energy generator. They, like others that followed them, were not interested in the meditative energy, of course, they were interested in electricity! Since then, a lot has happened on harnessing the potential energy of the waves.
Yoshio Masuda, a former Japanese navy officer, may be regarded as the father of modern wave energy technology, doing research in Japan since the 1940s. He developed a navigation buoy powered by wave energy, equipped with an air turbine, which was named an oscillating water column. These buoys were commercialized in Japan in 1965, and later in USA. A renewed interest in wave energy was motivated by the oil crisis in 1973. Englishman Stephen Salter's 1974 invention, known as Salter's duck or nodding duck, could stop 90% of wave motion and could convert 90% of that to electricity giving 81% efficiency. In Japan, Masuda promoted the construction, in 1976, of a much larger device, a barge measuring 80m x 12m, named Kaimei, used as a floating testing platform housing several oscillating water columns equipped with different types of air turbines.
In the 1980s, as the oil price went down, wave-energy funding was drastically reduced. Nevertheless, engineering and prototype developments continued. More recently, thanks to growing awareness to climate change, there is again a growing interest for renewable energy, including wave energy.
The world's first marine energy test facility was established in 2003 to kickstart the development of a wave and tidal energy industry in the UK. Based in Orkney, Scotland, the European Marine Energy Centre has supported the deployment of more wave and tidal energy devices than at any other single site in the world. Its grid connected wave test site is situated, on the western edge of the Orkney mainland, and is subject to the full force of the Atlantic Ocean with seas as high as 19 metres recorded at the site.
In the first week of June this year, Gibraltar made history with the connection of its new wave power project, an array of ocean energy converters from the Israeli company, Eco Wave Power. Though small in size, it is the first clean power plant of its kind in the EU. When fully built out, the plant is expected to meet 15% of Gibraltar’s electricity demand. The company claims that the Gibraltar array is the first grid-connected, multi-unit wave power plant in Europe, to operate under the terms of a commercial power purchase agreement.
Drew Barrymore said, ‘’I pray to be like the ocean, with soft currents, maybe waves at times. More and more, I want the consistency rather than the highs and the lows’’, and this consistency of waves is what makes wave energy promising. But there are two challenges to overcome – salt water corrosion, and the ability to handle a combination of high wind and high seas. These two factors are a big reason why wave power has not scaled up as quickly as solar and wind energy. But it seems that all this is changing.
The next couple of years should be big for wave energy technology around the world. Besides Eco Wave Power which is gearing up for 111 megawatts worth of projects in the near future, the US Navy has also been quite active with a free-floating buoy-based system called the StingRAY, developed by Columbia Power Technologies.
John Burroughs will be smiling happily, as he watches all these developments, because, in 1916 he had said, ‘The fuel in the earth will be exhausted in a thousand or more years, and its mineral wealth, but man will find substitutes for these in the winds, waves, the sun’s heat, and so forth’....