Presentations

Abstract

The global increase in electricity demand is accelerating worldwide wind energy deployment, not the least in the European continent. At the same time, land but also offshore space such as the shallow thus popular North Sea waters, are becoming more scarce for application of wind energy. Hence the need to make the most out of the available area by increasing wind farm efficiency and energy density, is more actual than ever. The physical characteristic dominating these aspects is the wind turbine wake, a downstream region of velocity deficit, featuring higher turbulence and a complex helical vortex structure. The impact of this velocity deficit is a power loss for the downstream wind turbine. In this work the application of a turbulators, attached to the blade tips by means of segmented Gurney flaps, is demonstrated in the field. Scanning LiDAR measurements have confirmed earlier wake breakdown resulting in a reduction of wake deficit by approximately 10% at various downstream distances. Using crude assumptions, this implies a 4% relative increase in wind farm efficiency for a typical wind farm with outer rows of wind turbines with segmented Gurney flaps. In summary, a very successful field test campaign was executed which demonstrated the use of segmented Gurney Flaps as a promising add-on to promote enhanced wind turbine wake recovery for improved overall wind farm farm performance.