StatoilHydro Launches the First Floating Wind Turbine

The term "offshore wind" usually refers to wind turbines erected on islands or in shallow water off a mainland coast, as with the infamous Cape Wind project. But the real prize would be floating turbines far enough from shore to be out of sight, catching the strongest, most constant winds available. It's a technical challenge, but Norway's StatoilHydro has just set up the world's first such wind turbine, the 2.3 megawatt Hywind.

Like an iceberg, the Hywind is more underwater than above, supported by a 100 meter long flotation device beneath the surface and moored to the bottom by, potentially, several hundred meters of mooring cable. From its mooring points, it will be connected to land by high-voltage power cables running along the seabed.

Above the water is a fairly standard 65 meter tower, and the Siemens turbine providing the power has an 80 meter span. (For scale, the little white and red dot in the company's illustration of the turbine, at right, is a large helicopter.) As might be expected, this pilot project is atrociously expensive, with StatoilHydro itself putting in over $60 million and several other companies providing smaller amounts.

The ocean is a rough place to be year-round, even for something as tough as a wind turbine. It'll require extra corrosion protection, lightning protection and servicing systems that land-based turbines don't bother with, and any unexpected problems will require difficult maintenance.

But if all goes well, StatoilHydro will be the owner of a wind turbine that has far fewer intermittency problems than existing systems, along with plenty of open ocean territory (especially around its old oil rigs) and lots of demand from the European energy markets. Depending on costs, floating wind turbines could easily beat out existing renewable energy technologies -- though we'll have better picture when the testing is done two years from now.