As the worlds first floating wind farm, one of the main technical challenges in the design phase of Hywind Scotland was the uncertainty related to wake interaction effects between the floating wind turbines. In this paper, we address this challenge by presenting an analysis of full‐scale measurements from the Hywind Scotland wind farm. Measurements of the floaters' roll, pitch and yaw motions are presented, both in the form of statistical data and response spectra. The floater responses of a turbine in free wind and a turbine in wake are compared, and the influence of different atmospheric stabilities on the floater motions is investigated. Despite the large distance between the turbines of 9 rotor diameters, wake effects in the measured floater motions are observed at the downstream turbine. Furthermore, both the wake responses and the free wind responses show a clear dependency on atmospheric stability. However, overall motions are small for all wind speeds, showing that the design performs satisfactorily in both free wind and wake conditions.

Estimates of atmospheric turbulence performed by both fixed and floating vertically profiling, conically scanning wind lidars are affected by the measurement volume and turbulence structure, among others. We study this phenomenon by simulating the lidar measurements within synthetic fields of atmospheric turbulence. We use the simulations’ framework to assess the impact of buoy motions on turbulence estimation. Simulation results show that the buoy’s translational motions impact turbulence estimates the most. We also apply the simulation framework to analyze measurements from a floating lidar measuring nearby an offshore meteorological mast for a period of six months. The analysis of measurements is presented both without and with motion compensation. In general, we find from both simulations and measurements that the buoy motions do not impact the mean horizontal wind speed significantly, in agreement with previous studies. However, both simulations and measurements show that the standard deviation of the horizontal velocity is overestimated by the floating lidar. When we correct the measurements based on compensation factors derived from the simulations, the mean bias of the horizontal wind speed standard deviation changes from 18–19% to 5–21%, with large reductions at the first four heights closest to the surface and a slight increase at the highest vertical level.

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