Posters

Abstract

In the recent years, floating lidar has become the de-facto standard measurement technology for offshore wind resource assessments. This is to be confirmed once again by the Technical Specification (TS) IEC 61400-50-4, of which a Committee Draft (CD) is expected for early summer 2022. A mandatory task, according to the TS, is the monitoring of the floating lidar measurements on the basis of comparisons to reference data from Numerical Weather Prediction (NWP) datasets or similar. As part of the project initiative “Digital Wind Buoy”, we have developed a respective methodology and implemented it in an online dashboard and monitoring system. For this we consider different reference data sources, the quality and suitability of which are compared in an in-depth study. The additional data provided by the NWP datasets improves the data monitoring by supplying a reference dataset for a constant plausibilisation of the ongoing floating lidar measurements. General wind and weather data plausibility checks are performed by comparing and correlating the floating lidar data to the NWP data to discover potential defects or ambiguities. By monitoring the overall weather conditions on site, the cause of periods with low wind data availability or excessive wiper activities, which might be indicators for a hardware failure, poor lidar performance or an upcoming lidar fault, are investigated to lower the risk of misinterpretation (e.g., by assuming unfavourable atmospheric conditions). Furthermore, wave forecast data are used to schedule emergency power supply runtimes as well as service and maintenance trips. Based on this operational monitoring and the associated plausibilisation action, we also discuss the R&D question how measurement data from floating lidar deployments can complement the global NWP and reanalysis datasets, respectively, and how more and more observations offshore can add to an improved understanding of the marine wind conditions in the respective areas.