Why biodegradable solutions in offshore wind farms?
Current erosion protection in wind farms is made of various stone and concrete structures, which must be completely removed after the life of the wind farm (20-25 years), together with the wind turbines. This can have major consequences for the underwater ecology, as it also removes all epifauna that has colonized on the hard substrate during the lifetime of the wind farm. Since 2017, it has therefore been laid down by law that an offshore wind farm must be designed and built in such a way that it improves the marine ecosystem, thereby preserving marine species and habitats that occur naturally in those areas. For example, an artificially hardsubstrate can create a favorable living environment in which protective native species, such as flat oysters (Ostrea edulis), can establish themselves.
BESE-products aids in improving marine life within windfarms by providing a suitable settlement substrate for marine species, like oysters. And because of its biobased and biodegradable nature, removal activities of the material are not necessary after the lifespan of the wind farm. The marine life that has overgrown the products can remain and enhance the natural biodiversity in the area, even beyond the wind farm's lifespan.
Which products do we offer?
BESE - elements
BESE-elements can be used in wind farms, for reef restoration - BESE-elements mimic the complex 3D structure of a natural reef and offer reef species a habitat to setlle and grow. Once the species have overgrown the structure, BESE-elements degrade, and a natural reef is left behind. This solution is already used on large scale in Australia to promote subtidal reef restoration, where oysters and soft coral have colonized the BESE-elements and enhanced the diversity and abundance of fish assemblages and the density of harvestable fish at the restoration site.
More about BESE-elements can be found on the product page or factsheet
BESE- reef paste
The reef paste designed by BESE products can be used in a windfarm as:
- A paste or coating which can be applied on surfaces of the monopile or scour protection, to enhance the settlement of shellfish species especially oysters, on the substrate.
- Single blocks. The reef paste can be put into any mold to form blocks, which can be placed on the seafloor between the monopiles or on the scour protection. Again the paste promotes the settlement of reef building species like oysters.
More about the products specifics can be found on the product page or factsheet
One of the cheapest ways to restore oyster reefs is by solely outplacing settlement substrate and rely on the oyster larvea to find their way to it. Usually this substrate is shell material, as from research this is the most optimal substrate. However in dynamic locations like offshore wind farms shell material often gets buried, due to for example sand waves. Or the shell is rolling over the seafloor which makes settlement for oyster larvea on the substrate impossible. To make sure the shell substrate is available for larvea it can be put into biodegradable bags before placing it on the seafloor. The bags make sure the shell material stays stable on the seafloor and does not get buried as easily as single shells. In the lifetime of the bags a reef can form on the shells.
More about the mesh bags and product specifics can be found on the product page or factsheet