The Netherlands has found a way to protect the migration of birds: to close the turbines of its wind farms for a few hours. This is what happened last Saturday, when the wind turbines in the towns of Borssele (west) and Egmond aan Zee (north) were turned off for four hours to guarantee their passage, according to the Dutch executive.
The authorities foresee more stoppages in the coming months. Starting in the fall of 2023, the pilot test is expected to end and the measure to take effect. In this way, wind farms will be closed more frequently “to allow smooth passage of migratory birds through the North Sea wind farms.”
In addition, to give the birds safe passage, wind farm owners will now reduce the speed of the wind turbines to a maximum of two revolutions per minute during the expected nocturnal migration peak.
“This is a pioneering measure, nowhere in the world are offshore wind farms closed to protect birds during mass bird migration,” Dutch Climate Minister Rob Jetten explained in a statement.
With this measure, Jetten assures that they want to “keep the impact of wind farms on nature as small as possible” and values ​​the joint work between companies and administrations.
At the end of 2022, a PhD student at the University of Amsterdam (UvA) delivered a bird migration prediction model that anticipates bird migration within two days. The model uses weather data and various bird radars in the North Sea. In addition, a group of migratory bird experts also predicts the probability of migration of large birds two days in advance.
With this information, the two-day time frame gives grid operator TenneT time to ensure the stability of the high-voltage grid. This time is also used to inform all parties involved and to carefully initiate the shutdown of the turbines.
“Twice a year, in spring and autumn, millions of birds migrate across the North Sea on a few nights. With the increasing number of wind farms in the North Sea, it is extremely important that we do this in the most ecologically responsible way possible with minimal impact on the North Sea. The temporary shutdown of the turbines during bird migration contributes to this,†says Tim van Oijen of Vogelbescherming Nederland.
