Wind Farm Cluster Wakes

The last couple of decades have seen developments of large wind farms partly in close distance forming “wind farm clusters.” Those wind farm clusters often consists of several hundreds of wind turbines which interact with the atmospheric boundary layer. Measurements of wind farm cluster wakes have been carried out in recent years showing wake length of up to 100 km downstream of wind farm clusters. The advancement of remote sensing tools is promising as typical scales of the wakes are approached. As several orders of magnitude in scales have to be covered from the flow around the single turbine to the far distant wake, there are many challenges in deriving models and wind farm parametrizations for flow models. Single situations have quite extensively been studied based on remote sensing and also aircraft data. However, the impact on wind resources and annual energy production (AEP) is so far based on model results only and needs further insights using wind farm production data that will be available in future years due to the current expansion of wind farms.