Wind farm: Seeing which way the wind blows, off the French shore

Support for the onshore wind energy industry in France has blown hot and cold in recent months, but government backing for offshore was reinforced in April by its decision to award tenders to build offshore wind farms to produce 2 GW of energy.

French company Nass&Wind Offshore, is taking full advantage of this momentum and investing in LiDAR (Light Detection and Ranging) measuring devices – a move it believes will give it a competitive advantage when the government decides to release a second offshore tender later this year.

LiDAR is an optical remote sensing technology that Nass&Wind is using to measure the speed of wind and turbulence up to an altitude of 200 metres – higher than the nacelle generally located 100 metres above sea level, says the company. Nass&Wind has now installed two of these devices off the coast of western France to try to accurately determine the power production potential of planned offshore wind farms.

When announcing the results of the tenders in the spring, the French government acknowledged that it had originally announced plans for 3 GW of new offshore wind capacity. The French energy minister of that time Eric Besson said that a second tender round would be launched later this year to award the remaining 1 GW.

“The data collected by these two devices will be compared and analysed daily for several months,” said Nass&Wind Offshore. This will allow the company’s team of engineers “to obtain unique wind data correlation” and provide the firm with “a competitive edge” with which to woo energy providers and industrial partners when answering the second call for tenders.

Various companies are looking at how they can use similar technology to best measure potential power from offshore wind.  Indeed, the expectations for nacelle-based and scanning LiDARS for power curve testing was a key subject of discussion at the technology workshop held by the European Wind Energy Association (EWEA) in Lyon, France in June.

Last year, for the first time, a full-size prototype of a floating LiDAR offshore wind resource assessment system, known as a FliDAR, was successfully tested 15 kilometres off the Belgian coast. Developed partly by the global energy consultant 3E, Flidar is designed to withstand wave heights of more than six metres and was tested in wind speeds of up to 25 metres per second. Data from the device, based on an industry standard buoy, is retrieved and communicated to the shore via satellite.

A report published by the International Energy Agency (IEA) last month forecast that France will be one of the main players in the growth of offshore capacity with an estimated increase of 1.5 GW between now and 2017.

The most up-to-date figures for offshore capacity in Europe can be found in EWEA’s publication – The European offshore wind industry – key trends and statistics 1st half 2012.