Especially in northern regions many residents can be afflicted by the shadow effect that the wings of the wind turbines make during the winter months. Residential complaints can affect the positive view on wind turbines in the local area. Therefore, Spica was asked to develop a solution to solve this problem.

The shadow detection system is built into the control system of the wind turbine. Based on the angle, position of the sun, distance from the wind turbine to surrounding residential areas and the radius of the wind turbine, VSDS can predict when shadow flicker is about to happen and thus pauses the turbines operation until the shadow flickering has stopped. The system also makes sure that wind turbines resume production as soon as the conditions allow it, thereby improving the energy output.

The VSDS system is designed and developed by Spica Technology for Vestas Wind Systems A/S. Vestas has all the patents and IPR for this product. It is a special add on product for new turbines around the world and it has to comply with a lot of different standards and regulations, the system is produced at Spica Technology in Denmark.