Utility ENBW trialing floating wind power turbines to expand usable area

The German energy company Energie Baden-Württemberg (EnBW) is running trials of a floating wind turbine that could soon compete on costs with fixed offshore installations, the Frankfurter Allgemeine Zeitung reports. The plant, produced by German firm Aerodyn, is attached to a partially submerged buoy held in place by a circle of seabed anchors, allowing its two 7.5 megawatt turbines to turn freely in the wind. While the one-to-ten scale model is only being tested in a 10 metres deep lake, the final 200 metres tall structure could become cost-efficient at depths of 35 metres in the open sea, the company believes. Fixed offshore turbines are generally limited to depths of 50 metres due to cost restrictions.

Floating wind turbines are currently more expensive to produce than fixed ones and are also more susceptible to bad weather. But they are cheaper to install and maintain. Energy firms believe material costs will also fall in the future. Several pilot projects are already in place, including in the North Sea. EnBW plans to carry out final tests of its floating turbine off the coast of China next year, the FAZ reports.

Offshore wind power is a key component of Germany’s plan to produce 65 percent of its power from renewable sources in the next decade. The country has recently expanded its 2040 offshore capacity target to 40 gigawatts, and has just published a draft of possible new wind farm locations. But the industry faces many challenges, mainly due to environmental concerns and increasing costs as shallow, relatively easy-to-exploit sites are filled. Floating turbines offer a possible solution to mitigate both problems, but are still too expensive.