What can developers or owners of wind farms do to take into account birds, bats and marine life? And what requirements must the government set in advance to protect nature in the North Sea? The Wozep (Offshore Wind Energy Ecological Program) research program of Rijkswaterstaat has been researching this since 2016 on behalf of the Ministry of Economic Affairs and Climate. Today the mini-film "Wind energy at sea and nature" is launched, in which the answer to these questions is central.
Important results so far
- Wozep investigates more precisely which sound frequency is most harmful for porpoises and which measures help. Bubble barriers and jackets around the piles are already being used successfully. Based on Wozep's research, the maximum underwater noise standard for wind farms built after 2023 has been set at 168 dB.
- In 2020 and 2021, Wozep researchers will 'send' approximately 70 sea and coastal birds such as terns, lesser black-backed gulls and herring gulls to monitor their daily flight movements in and near a wind farm.
- Bats fly to England by sea. They do this mainly in the fall, but also in the spring. Wozep has discovered that they mainly start the crossing when there is little wind and in certain weather conditions. If the mills are then stopped, that could save 40% victims.
- Migratory birds are researched during the massive bird migration in the spring and autumn, and in particular the weather conditions in which they may fly at rotor height. Using the knowledge from the research, a prediction model is being built, with which the intention is to predict 48 hours in advance whether large numbers of birds will migrate. Stopping the mills during mass migration saves a considerable number of victims among migratory birds.
What is being researched
From 2016 to 2023, Wozep conducts research into the effects of the construction and use of offshore wind farms on:
- Harbor porpoise, harbor seal and gray seal; these species experience nuisance from the pile-driving noise during the construction phase of a wind farm.
- Sea and coastal birds; some species avoid the area, making their habitat smaller or more difficult to reach. Species that the wind farms do not avoid can be hit by the rotor blades.
- Migratory birds and bats; they are at risk of collisions during the spring and autumn migration.
- The processes in the North Sea. The posts of the mills can influence, among other things, the marine life that feels at home on the bottom, and on waves, currents and stratification of the water in temperature and oxygen.
Towards a sustainable energy supply
Wind energy in the North Sea offers opportunities for a sustainable and prosperous future. By 2030, at least 27% of all energy must be sustainable. Wind energy at sea is indispensable to achieve this goal. In doing so, care must be taken with the interests of all users of the North Sea, including nature. In the Climate Agreement it has been agreed that the further roll-out of wind energy at sea will take place within the ecological capacity of the North Sea. In the recently concluded North Sea Agreement, agreements have been made about the balance between wind energy at sea, nature and fisheries. It has been agreed to monitor the effects on nature and conduct additional research.