Presentations

Abstract

The continuous increase of wind turbine size, and the publication of the latest IEC standards [1] and [2] that allow measuring wind speed for power performance testing with lidar devices, raises the question whether a lidar could produce comparable results to those of a met mast while reducing the high installation costs. A power performance test, carried out in cooperation between NRG, ZX Lidars, DNV and Enel Green Power in a flat-terrain wind farm located in the US, allows the comparison of the three available technologies (anemometers, ground-based lidars and nacelle-mounted lidars). Results of the project indicate that both continuous-wave lidar AEP fall within the uncertainty range of the cup anemometer-based AEP estimates, with the nacelle mounted lidar AEP ratio being 1.6% greater than the mast. The associated AEP uncertainties of both lidars are similar to the cup anemometer with the ground based lidar having the highest AEP uncertainty, which is 0.21% greater than the cup anemometer.    The aim of this activity is to evaluate not only the results, but also to put the focus on each of the different methods/standards that apply in a power performance test. The outcome of this project has been summarized and is presented here as a list of “lessons learned”. Some of the aspects that have been found relevant and taken into consideration are as follows:  * Installation aspects (device mounting; health and safety; permits and licenses) * Measurement campaign aspects (data availability; specific climatic variables measurements; measurement sector selection and its dependence on device technology; terrain correction) * Technology acceptance (cost; OEM warranty terms and conditions; measurement uncertainties)  Reflections about these topics, and other practical aspects to be considered during the planning phase of a power performance test and when selecting a measurement device, are presented in this contribution. [1] IEC 61400-50-2: 2022 Wind energy generation systems – Part 50-2: Wind measurement – Application of ground -mounted remote sensing technology (Edition 1.0) [2] IEC 61400-50-3: 2022 Wind energy generation systems – Part 50-3: Use of nacelle-mounted lidars for wind measurements (Edition 1.0)