Waves

With an emerging need to shift from fossil fuel, wave energy has again got its deserved focus as part of future energy supply. UK have been leading the way, with good feed-in tariffs and adventurous challenges like Saltire Prize, which is Scotland's £10 million competition to accelerate the commercial development of marine energy. But not all coastal countries have this focus, and an example of this is Norway. Despite its long and energy rich coast, wave power is almost absent in its debate regarding future energy supply. There is probably numerous reasons for this. One is petroholisme. After the last oil-reserve findings, the country's petro-Hallelujah chorus reaches new heights. Another is that Norway from long before oil was found, has been blessed with hydro power. It has not always been a lack of wave energy interest in this country though. In the years after 1973 oil crisis, something was started in the Nordic countries. Denmark decided to further develop their small-scale wind energy. Sweden wanted to develop bio-energy based on their wast forest resource. Norway (as several other countries) started development of wave energy. We all know how it went with the Danish wind energy industry; It got so successful that the original companies are now experiencing tough competition from all over the world. The Swedish bio-energy also became a huge success, and did in 2010 count for 32% of the country's energy consumption, and is growing rapidly. Despite some visionary researchers relentless efforts, Norway gave up their wave energy development, somewhere in the 80ies. As like in all countries which had given wave energy a try, patience was not present. One had experienced setbacks and problems. Sustainability was an impossibility in the oil lubricated fast economy.

Taking a step aside, what is wave energy – and why should we still try to develop it? Waves are created by wind blowing along at sea-level. Furthermore, the wind is created by the sun as its heating creates low and high atmospheric pressure. Only a small portion of the solar energy is converted into wind energy, and of this only a small part is transformed into wave energy. But in both these energy transformations, there is an enormous increase of the energy density. Just below the sea surface, the average energy density is many times higher than the density of wind energy. When the wind blows in the same direction over time, a dominant wave direction is created. The high energy density means that a properly designed wave power unit will have a beneficial relationship between the size (or cost) of the structures and the energy produced.

In these facts is there an explanation of why wind turbines are so huge, and why most wave energy converters are by comparison small. If a land-based or ocean-grounded wind turbine is huge, then the floating wind turbine is a giant. This is simply due to hydrodynamical stability. Despite a large media-focus for the past ten years or so, it still exists only two floating MW wind turbines in the world. Norwegian Statoil's 2MW Hywind was the first. In addition to generate electric power, there is no doubt that Hywind is also generating not easily accessible goodwill for an oil-company which has invested in more than 13.000.000.000 Norwegian kroner in Canadian tar-sand.

Putting all competition between renewables at the side, there should be no doubt that to be able to make the shift from fossil fuels, we will need a mixture of all sort of renewable sources. In countries similar to Norway, floating ocean energy converters will have an advantage for several reasons, like that they may be installed offshore and away from the coastline which is precious to so many of us, like they will not compete for the vital fishing-banks with the fishermen, like that there simply isn't enough shallow waters if ocean energy is to give a significant contribution. The mixture in Norway will have to be different from the one in Spain, which again will have to be different to the one in India, and so on. There is so much more to say about this, but to short of; When searching for future renewable sources, it is vital to have patience and think sustainability and long-term. After all that is what future is about. Long-term.

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Open wave energy project is an open innovation arena to assist collaboration, prosperity and to boost the development of ocean energy. It is an initiative created by ocean energy developers, for ocean energy developers. Whether you're an innovator, decision maker, supplier, student or just above interested in sustainable marine energy, we imagine you will find this site useful.

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