IEA Wind Task 32

Wind turbine power performance testing is a practical and technical challenge offshore and in complex terrain (hills and forests). Nacelle mounted lidars have shown to be reliable solutions offshore, since they can replace very expensive offshore meteorological masts. Nevertheless, offshore wind turbines are becoming very large and measuring far enough upstream so that the measurements are outside the induction zone (2.5 rotor diameters udstream) is becoming challenging. In mountainous or forested areas, the flow is influenced by the terrain features. For trubine testing, the wind speed measured at 2.5D upstream needs to be corrected to represent the wind speed at the turbine location. This correction is derived from a site calibration measured with two met masts. 

A new approach using nacelle lidar measurements closer to the rotor can be a solution to both of those issues. In this project, recommended practices on how to apply this method offshore and in complex terrain will be drawn from comparison of results at several sites. In addition, site calibration measurement using nacelle lidar will also be tested at different sites. This project is part og the power curve work stream of IEA Wind Task 32 - Wind Lidar Systems for Wind Energy.