Wind power drifts out to sea

Floating turbine to push technological boundaries

Can we harness the power of the wind using the technology of fossil fuels? The recent installation of the world’s first full-scale floating wind turbine, which uses stabilising technology first developed for oil platforms, may be the key to taking wind turbines further out to sea.

The ‘Hywind’ prototype, built by oil giant StatoilHydro, is now in place for a two-year trial off the Norwegian coast, based on a relatively simple design. A conventional 2.3MW Siemens turbine is placed on a weighted ‘spar’ buoy that extends 100 metres below the surface to provide stability and a low centre of gravity. Three anchor points will prevent the turbine from floating away, as well as linking the structure to undersea transmission cables.

“As you get into deeper water, the cost [of existing fixed turbine technology] escalates,” explains Benjamin Sykes, Senior Technology Acceleration Manager at the Carbon Trust. As well as benefiting from higher and more consistent wind speeds further out at sea, floating turbines would bring offshore wind within reach of major consumption areas, such as the US and Japan, that lack shallow water sites. According to StatoilHydro, they can be placed wherever ocean depth is between 120 and 700 metres.

StatoilHydro has invested NOK 400 million (£42.8 million) in the research, development and construction of the pilot. – Nick Chan

15 December 2009

Nick Chan