Wind energy and nature
Categorie(s): Ecology, News, Sustainable Energy
Research shows: first offshore wind farm in the Netherlands has positive impact on marine life
Because many people do not want modern windmills ‘in their back yard’, wind parks are being built in sea, where people can not see them. But now people worry that they disturb the nature in the seas. A good reason to do research in and around the first offshore wind farm in the Netherlands near Egmond aan Zee. Now we know that it has positively impacted life in and around the sea, and has had hardly any adverse effects.
The wind farm has been fully operational since 2007. It is situated between 10 and 18 km off the Dutch coast and spans an area of 27 km². The wind farm provides electricity for over 100,000 households each year.
Five years of scientific research
IMARES, NIOZ and Bureau Waardenburg are the foremost research institutes in the Netherlands. They were asked to research the impact of the wind farm on life in and around the sea. Five years of intensive scientific research followed. Four categories of animals were investigated: fish, birds, marine mammals and benthos (life in the bottom layers). The most important conclusion was that the wind farm had mainly positive effects on life in and around the sea.
RESULTS
Fish
This study investigated the general presence of fish in and around the farm, but focused on the behaviour of two species: cod (photo) and sole. It appears that cod likes to stay within the realms of the farm, as higher concentrations of cod have been observed around the pillars of the wind turbines. This is probably due to the absence of fisheries in this area and the copious amount of food sources near the pillars. Fishing in the wind farm, or within a 500 metre radius of the border of the farm, is forbidden for safety reasons. The study revealed no impact on the behaviour of sole. For the purposes of this study, tiny, innovative transmitters were implanted into the fish, which then communicated with receivers on the ocean floor.
Birds
Approximately five million birds fly within the vicinity of the wind farm each year. The study has shown that most of these birds avoid the farm, and fly over or around it. Birds that do enter the farm, know how to avoid the wind turbines. This means that only a tiny percentage – approximately 0.01% – are actually hit by the blades of the wind turbines. Researchers used radar technology to map their migration. Surprisingly, the wind farm proved to be ideal for the Great Cormorant (Photo). Cormorants need to dry their feathers after fishing, which can be easily done at the wind farm. They pick a spot on one of the wind-turbine platforms and spread their wings, which they do in large numbers. The Cormorants seem to be fond of the place. They come there in great numbers both in summer and in winter. Normally they do not come so far out of the shore. Cormorants eat fish, daily about half a kilo. In the windpark there is plenty of fish: the foundations of the turbines are full of algae, sea anemones, seastars, mussels etc. They attract worms, shrimps and fish. And no fisheries. Add the 36 turbines to dry your feathers, and you can speak of a paradise for the cormorants
Marine mammals
Two types of marine mammal were investigated in the study: the seal and the harbour porpoise (photo). Researchers did not find any effects of the wind farm on seal behaviour. This is mainly due to the great distances seals travel. Seals can be observed throughout the North Sea including the wind farm. Hence the impact of such a farm, covering only 27 km2, is not discernable. Porpoise populations were measured in the wind farms using underwater microphones. The results revealed higher porpoise numbers in the farm than outside of it. This is possibly due to food sources available within the farm, or the peacefulness of the farm in what is otherwise a relatively busy area.
Benthos (bottom life)
Research has revealed no effect up to now on benthos in the sandy areas between the wind turbine pillars. This may be due to the fact that young shellfish only mature once in every five to ten years, something that hasn’t occurred in the last couple of years. However, other species have been found on the pillars and on the stones surrounding the pillars, which has led to increased local biodiversity. The researchers found 33 animal species on and around the pillars not known to live there earlier.
Source http://www.noordzeewind.nl/
One other positieve effect of wind turbines could be protection against damage from storms: see