IEA Wind Task 32: Wind lidar systems for wind energy deployment (Working period 2019-2021)

Description LIDAR (‚Light detecting and ranging') systems have been used in the field of wind energy since about a decade and have contributed significantly to a cost reduction in the last few years. Although the degree of maturity of technology has risen in the last years, wind-LIDAR-devices are still not fully accepted in the wind energy industry.

To minimize the existing obstacles, in 2013 the Task 32 of the IEA Wind was launched, which has been dealing with the possibilities and challenges of the application of LIDAR-systems since then. Through mutual exchange of experiences and global networking new knowledge is generated and the existing obstacles are reduced.

Due to the complex topography of many wind turbine sites, the subtask "Site- Assessment" is of great relevance for Austria, especially as there are technical challenges regarding the investigation of site specific wind resources in complex terrain with LIDAR-devices. On the one hand, the lack of data availability on alpine and semi-alpine sites raises questions that could not be satisfactorily answered by experts from the industry and research. On the other hand, due to the measurement and operation principle of a LIDAR- device, the feedback of the signals to a point is subject to high inaccuracies when used in complex terrain. Also, the computational correction of terrain- related measurement errors using three-dimensional flow models has not been able to provide satisfactory solutions so far.
The planned national contribution of Energiewerkstatt directly addresses the above mentioned aspects: Ten LIDAR measurements, which have been performed at sites with different local conditions, are evaluated regarding the site-specific impact of environmental conditions on data availability.

Furthermore, Energiewerkstatt organizes two thematic workshops, which deal with the challenges of assessing wind resources at alpine sites. In this context, the participants evaluate the performance of the two measurement technologies (i.e. LIDAR and conventional mast measurement) using data

from combined LIDAR- and mast measurements in terms of measurement deviations and measurement accuracy. Based on the results recommendations regarding the use of LIDAR equipment in complex terrain are established.

The results of the cooperation are published in the form of guidelines with recommendations on the various applications of LIDAR technology in the field of wind energy. These publications also contain information regarding international definitions and classification systems and serve as inputs to norms and standards. In addition, to ensure a smooth know-how transfer of international expertise to Austria, the Energiewerkstatt acts as a national interface between experts of Task 32 and the Austrian wind energy scene. Involving the Austrian Wind Energy Association, international experience is disseminated in Austria.

Publications are available in the previous working period on the German part of the website.

Project leader:

Christoph Tiefgraber
Energiewerkstatt, association register No. 569578895 Heiligenstatt 24
A-5211 Friedburg