Offshore wind farms and protection of nature
Wind energy is an indispensable element in the efforts to meet climate objectives. In Western Europe, there are plans to construct a great many wind turbines in the North Sea. As no one lives here, nobody will be inconvenienced by the noise from the turbines or the resulting change in the landscape. In ten years’ time, expectations are that the North Sea will accommodate hundreds of offshore wind farms.
However, the North Sea also provides a habitat for bats, seabirds, seals, porpoises and fish, and the construction of so many wind farms will cause rapid changes to these habitats. How can you call wind energy green if the construction and operation of these wind turbines have such a negative impact on nature?
“Offshore wind farms are an important element in the fight against climate change, but it would be a bitter pill to swallow if the cure turns out to be worse than the disease.”
Wageningen University & Research is investigating the impact of offshore wind turbines on nature, as well as how to minimise it. We are predominantly researching the sum total of the wind farms’ impact as all of these offshore wind farms are creating a new North Sea landscape.
Bats
Bats may not be the first creatures that spring to mind when you talk about offshore wind farms. However, they fly over the North Sea all the time to look for food (video), and some bat species cross the sea in spring to visit their breeding colonies before returning to their hibernation roosts in the autumn.
Bats are protected animals. Wageningen is using transmitters and other methods to investigate when bats fly, in what numbers they fly, what routes they take and in what weather conditions they fly, among many other factors. This is because they can be killed by the sails of wind turbines or the significant contrast in air pressure around wind turbines.
Porpoises and seals
Sea mammals such as porpoises and seals are particularly affected by the construction of wind turbines. The piledriving activities required for wind farms cause so much noise pollution that it can cause the animals to become temporarily deaf, to adjust their swimming routes or to lose their habitat altogether. Furthermore, as the animals use sound in order to find food, this noise pollution disrupts their search.
Seabirds
Wind farms can harm seabirds in two ways: they can be killed by the moving sails (especially at night when they can’t see them), or they can lose their habitat as they are frightened to come near the wind turbines. Some species are more affected than others. The degree of impact that wind turbines have on the different species depends on factors such as their flying skills, how high they fly and how easily they are distracted by objects at sea.
New nature
The drastic changes to the North Sea landscape are also causing new nature to appear. Mussels, soft corals, sea anemones and other sea creatures latch onto the foundations of the wind turbines, which attracts shrimp, crustaceans and fish. As a result, a completely new ecosystem is created.
Fish and bottom-dwelling creatures
We do not yet have a clear picture of how wind farms impact fish populations. Fishing boats are not permitted to enter wind parks as this can result in collisions with wind turbines and damage to electricity cables. As a result, the wind turbines may provide some fish species with a safe haven.
According to a study into the development of life on the seabed in areas where fishing has been banned for a significant period, factors such as storms, seasonal currents and available food supplies appear to be of equal importance to bottom-dwelling creatures (such as shellfish, worms and crabs) as the presence or absence of fishing ships.
Shaping the energy landscape
According to a joint report by researchers at WUR and ECN (the Netherlands Energy Research Centre), the transition to sustainable energy constitutes both a challenge and an opportunity to shape new cultural landscapes. In this report, they describe a qualitative approach involving environmental, sociocultural, economic and technological criteria in addition to specific technical requirements such as accessibility for maintenance. This also leaves room to consider other functions that wind farms can serve, such as the cultivation of mussels or seaweed. For this purpose, WUR is also conducting research into safe joint use of wind farms.
Environmental considerations
During her inauguration, WUR Professor of Marine Animal Ecology Tinka Murk spoke about how economic activities can go hand in hand with the maintenance of a healthy ecosystem (see the video here): “We must ensure that the North Sea remains sufficiently rich and diverse to adapt to new circumstances. To do this, all ecological functions must be fulfilled, and this will only be possible if sufficient diversity of habitat is maintained, certain areas are left untouched, and if activities in the North Sea are made more sustainable. From the very start, all plans must take the risks and opportunities for the North Sea environment into consideration.”
For more information:
- see our dossiers on Offshore Wind Farms, Porpoises, or Seals (in Dutch only)
- Article in Wageningen World: Leven in een Windpark (Life in a Wind Farm – in Dutch only)
- Nieuw leefgebied bodemdieren op oude gasplatforms in de Noordzee (Bottom-dwelling animals find new habitats in the North Sea; in Dutch only)
- Succesvolle inrichting van energielandschappen vereist nieuwe denkwijze (Successful design of energy landscapes requires new ways of thinking, in Dutch only)
