A wind turbine extracts energy from the wind, when converting energy from the wind into electrical energy. Further it and induces turbulence caused by its movement and friction with the air mass. Following this, the wind speed upstream (in front) of a turbine is higher than downstream (behind). This affects wind turbines standing downstream of another turbine resulting in less wind energy available and a more complex wind flow due to increased turbulence. One could say that the downstream wind turbine stands in the “shadow” of the upstream wind turbine.