Wind turbine dynamic shading: The effects on combined solar and wind farms

The Dutch climate agreement anticipates the large-scale implementation of solar and wind energy systems on land and water. Combining solar and wind farms has the benefit of multiple surface area use, and it also has the advantage of energy generation from both solar and wind energy systems, which is rather complementary in time; thus, a better balance can be found between electricity generation and demand and the load on the electricity grid. In combined solar and wind farms (CSWFs), the turbines will cast shadows on the solar panels. This concerns the static shadow from the construction tower of the turbine as well as the dynamic shadow caused by the rotating blades. This paper reports on the results of millisecond data monitoring of the PV farm of a CSWF in the Netherlands on land. Static and dynamic shadow effects are discussed, as well as their dependency on farm design. It is observed that the dynamic shade of the wind turbine blade causes serious disturbances of the DC inputs of the inverter, resulting in deviation of the maximum power point tracking monitored. The shadow of the wind turbine results in a total energy loss of about 6% for the given period, park configuration, PV modules, inverter type, and setting.