Offshore wind farms are a relatively new source of power that have gained tremendous popularity in Europe. Offshore turbines are often preferable to onshore projects since winds are typically steadier at sea; however, environmentalists have raised concerns about the impact they could have on marine life. In particular, the construction of monopiles to support turbines could destroy important seabed habitats. Surprisingly, Wilson and Elliott (2009) discovered that offshore wind farms can actually create thriving new habitats that far outweigh the amount of seabed disturbed by their construction. Noah Proser
Wilson, J.C., Elliott, M., 2009. The habitat-creation potential of offshore wind farms. Wind Energy 12, 203–212.
The researchers examined the effects of existing wind farms in the United Kingdom on colonization and fish-use. In particular, they focused on the habitat creating potentials of different types of scour protection. Monopile scour occurs when the sediment around the base of a monopile is washed away, compromising the integrity of its foundation. In order to prevent scouring, monopiles are surrounded with gravel, boulders, or synthetic fronds.
Though such protection disturbs the original seabed habitat, it also increases the surface area and complexity of the area around the monopile. Wilson and Elliott found that both boulder and gravel protection create more than double the habitat lost to their construction. While synthetic frond protection does not perform as well as the other methods, it still almost entirely makes up for the habitat lost.
It is important to note that the habitat created by the scour protection is different from what is lost; however, Wilson and Elliott contend that, since turbines are likely to be placed in areas with relatively sparse seabed, the added complexity from the scour protection will actually raise the carrying capacity of the surrounding environment. Further improvements can be made by using a blend of different scour protection methods on different turbines to promote diversity. ‘Reef balls’ (boulders with holes bored into them to maximize surface area used to create artificial reefs) can also be used in place of other scour protection materials. Furthermore, they suggest that wind farms could act as de facto marine sanctuaries because bottom trawling would not be allowed near them to prevent damages to the turbines.
Despite the concerns over the environmental impact of offshore wind projects, Wilson and Elliott assert that wind farms have a largely beneficial impact on marine life. They expect that the new habitats created by the turbines will boost fish populations and thus benefit fishermen as well. It seems as though productive, complex marine habitats may just be yet another benefit of wind power.