Offshore site selection for wind turbine projects require a detailed assessment of site suitability. In order to evaluate wind speeds at hub heights, the erection of an offshore measurement mast was inescapable in the past. An offshore mast is linked to a consumption of millions of US$, up to 18 months for preparation and installation along with health and safety risks during the construction. To avoid these factors and to make the assessment system more flexible, the replacement of the offshore mast with a floating LiDAR device offers several advantages.
To prove the accuracy of the floating LiDAR WindSentinel buoy manufactured by AXYS Technologies Inc., we recorded data over nearly three months with an offshore measurement mast and with the specified LiDAR device in the Taiwan Strait. Comparing these data, by using the mast as a reference, we are using scatter plot diagrams, in order to judge the data accuracy. Evaluating the data sets for 50 m, 90/95 m and 95/110 m, we achieved satisfying results. All of our generated R2 values fall into the best practice value acceptance criteria, set by the Carbon Trust Roadmap for the Commercial Acceptance of Floating LiDAR Technology, which is > 0.98.
Possible reasons for the non optimal R2 values are the bulky characteristics of the mast, over-speeding of the cup anemometers, the proven uncertainty of 2% for cup anemometers, disturbance of the LiDAR emitted laser, and the distance between the LiDAR and the mast.
Further evaluations on the LiDARs behaviour under the occurrence of typhoons have to be made and conclusions on the resistance of the WindSentinel under the harsh marine conditions in the Taiwan Strait have to be drawn.

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