SgurrEnergy Assesses Power Performance from Offshore Wind Turbine’s TP

A pioneering offshore wind measurement campaign by SgurrEnergy, part of Wood Group, has completed the first ever power performance assessment (PPA) using a scanning lidar deployed on the transition piece (TP) of an AREVA M5000 offshore wind turbine.

This success has huge implications for the offshore wind industry as this study shows that PPAs can successfully be conducted from the transition piece of offshore wind turbines, providing opportunity for simplified and more cost effective offshore measurement campaigns.

With ease of access, downtime should be less and therefore cost will be significantly lower. In addition, installation on the transition piece allows reference to guidance, standards and recommended practices developed for onshore, ground-based lidar measurements, supporting confidence in the results. A device measuring from the transition piece is easier to deploy and decommission, and facilitates easy access for maintenance.

The locations of the other wind turbines in the wind farm are fixed relative to the transition piece, but change in the reference frame of the nacelle as it yaws in response to changes in wind direction. As a consequence, a device on the transition piece can test the power curves of multiple turbines, in contrast to a device on the nacelle which can only test the power curve of the turbine on which it is installed.

Therefore, mounting the device on the transition piece can drive down the costs of the tests much further, and less than 1% of the cost of a comparable meteorological (met) mast based test. The accuracy of this method has been demonstrated by comparison with results using an offshore met mast.

Dr Peter Clive, senior scientist at SgurrEnergy, commented: “The results of this pioneering campaign will have a significant effect on how the offshore wind industry can use lidar to assess their wind turbines.

“This campaign shows how the industry can assess the performance of wind turbines and reduce risks with easy and reliable measurements.”

Press Release, May 20, 2014; Image: SgurrEnergy