Offshore wind profile characteristics and their impact on floating wind turbine power production
Copernicus|Nikolas Angelou and Camille Dubreuil-Boisclair|Oct 24, 2026
This new research from the Hywind Scotland offshore wind farm raises questions about how accurately electricity production can be predicted for increasingly large offshore wind turbines. As rotor diameters grow, turbine blades encounter significantly different wind conditions across their enormous swept area. The study suggests that conventional wind measurements and modeling assumptions may not adequately capture these variations, potentially affecting turbine performance estimates. While the research examined a floating turbine, the underlying issue is not necessarily limited to floating offshore wind. The abstract and conclusion of the paper is provided below. The full paper can be accessed at the document link on this page.
This new research from the Hywind Scotland offshore wind farm raises questions about how accurately electricity production can be predicted for increasingly large offshore wind turbines. As rotor diameters grow, turbine blades encounter significantly different wind conditions across their enormous swept area. The study suggests that conventional wind measurements and modeling assumptions may not adequately capture these variations, potentially affecting turbine performance estimates. While the research examined a floating turbine, the underlying issue is not necessarily limited to floating offshore wind. The abstract and conclusion of the paper is provided below. The full paper can be accessed at the document link on this page.
Abstract.
In this study, we investigate the impact of vertical wind shear and wind speed inversions on the power production of a floating offshore wind turbine. Using nacelle-mounted wind lidar data from a 6 MW turbine at the Hywind Scotland wind farm, we analyse inflow conditions and turbine performance during summer and autumn. The wind climatology shows that 33 % of examined cases exhibit non-standard wind profiles within the rotor-swept area, including negative shear and wind speed inversions. These conditions can significantly affect power production. In particular, in the below-rated wind speed range, we find differences ranging from 5 % to 10 % between wind profile cases with negative and positive shear. Our findings demonstrate that deviations from the logarithmic wind profile at the operating height range of modern offshore wind turbines can introduce substantial bias in a power curve verification procedure, with differences up to 20 % compared to a reference power curve of a fixed-bottom wind turbine. Nacelle-mounted wind lidars provide critical insight into the inflow offshore characteristics, enabling improved performance assessment of floating offshore wind turbines. The results highlight the need for an implementation of measurement strategies that capture wind conditions across the full rotor-swept area.
Conclusions
The wind profile characteristics at the North Sea over two seasons (summer and autumn) are studied using observations acquired by a nacelle-mounted wind lidar installed at the Hywind Scotland wind farm. We found that, in 88.5 % of the cases, modelling the radial speeds using a linear wind shear and veer across the rotor, along with an induction factor representing turbine operation, provided satisfactory results within the examined height range (100–200 m). The cases in which the model failed were associated with wind speed inversions occurring within the lowest 200 m of the atmosphere. Specifically, we show that floating offshore wind turbines in deep-water environments are frequently exposed to complex atmospheric conditions, including negative wind shear and wind speed inversions within the rotor-swept area.
These phenomena occurred in 22 % and 11 % of the examined cases and can have a significant impact on a power curve verification procedure that is based solely on hub-height wind speed without taking into consideration the variations in the vertical wind profile. We show that using only the hub-height wind speed as a reference wind speed to power curve verification leads to a reduced turbine power production, in respect to the corresponding power curve of a fixedbottom wind turbine, particularly under negative shear. This is demonstrated in the case of a 6 MW utility-scale floating offshore wind turbine that experiences mainly a wind-speeddependent pitch motion during operation. We report notable differences both in the mean and the standard deviation of the produced power between cases of wind profiles with positive and negative wind shear. Our findings confirm that nacelle-mounted wind lidars are an effective tool for detecting such inflow characteristics, providing critical insights for improving power performance assessment for FOWTs.