The ecological implications of large-scale offshore wind energy

How to roll out offshore wind farms on the North Sea with minimal ecological impact.

Guido Schild

The IABR project 2050: An Energetic Odyssey visualizes what the North Sea would look like if we were to build enough offshore wind farms to supply all of Northwest Europe with renewable energy by 2050. It is stated that this would require 25,000 offshore turbines of 10MW each. Together they would cover an area of some 57,000km2. Such an endeavour would clearly be laudable from a climate change mitigation perspective, as it would reduce the need for burning fossil fuels for energy production to near zero and, as such, make a massive contribution to the CO2 reduction necessary to halt climate change. But what are the effects of such a huge undertaking on the ecology of the North Sea? How would it affect the North Sea’s habitats and species?

Answering these questions is no easy task, considering the scale of the projected activity and the relatively limited knowledge on cumulative impacts in marine environments. In order to get a better grasp of the potential ecological consequences of large-scale offshore wind farms and potential ways to minimise negative impacts, Dutch NGOs The North Sea Foundation and Natuur & Milieu invited a group of ten senior marine ecologists from around the North Sea to the IABR and asked them to deliver their expert judgment and provide advice on how to move forward with offshore wind energy development in a sensible way.

The ecologists first pointed out that climate change is a global problem with local implications, also for the North Sea. If nothing is done to halt climate change, the North Sea’s ecology will be severely impacted by sea temperature change and acidification. Taking this into account, it is obvious that the North Sea should be part of the remedy by providing space for wind farms. It is clear that this will transform the North Sea from a severely degraded environment into a modified environment, influenced by man-made structures. The presence of these structures is likely to benefit some species, such as rock-dwelling fish, while species such as sea birds may suffer from it. In order to prevent severe and unexpected negative impacts, the group of ecologists recommend taking a step-by-step approach in the roll-out of offshore wind and monitoring the effects of each wind farm in such a way as to generate results quickly. These results can then inform the design and planning of the next wind farms in a process of adaptive management.

Because of the many uncertainties regarding the ecological impact of large-scale offshore wind, a precautionary approach should be applied. This means that wherever there is a possibility of severe or irreversible negative impacts, these impacts should be minimised or prevented, even if it is uncertain whether or not they will occur. Meanwhile, international cooperation is necessary to expand the knowledge base regarding the ecological effects of large-scale offshore wind, in isolation and in combination with other maritime activities. This means that research budgets should be shared and spent in a way that delivers the best results and that research methodologies should be harmonised as much as possible between countries. Likewise, an international approach to marine spatial planning is needed to ensure wind farms are optimally situated. Arguably, a development of such scale calls for a re-design of the North Sea, where old and new uses are awarded space according to their need and ecological impact. The European legal framework on nature conservation should be taken fully into account when developing large-scale offshore wind farms, as this is the minimum degree of protection required to safeguard detrimental effects on habitats and species. Finally, the ecologists stated the growing importance of marine protected areas in the face of increasing activities at sea. The more intensive our use of the sea becomes, the more important it will be to preserve ecologically important areas as natural reference points and refuges.

Clearly, these recommendations are not exhaustive. They do however, provide a good foundation for further thinking on how we can tackle the challenges we face in preventing further climate change without doing irreparable harm to the marine environment.

Guido Schild is Project Manager Offshore Energy at The North Sea Foundation

IABR Atelier 2050-An Energetic Odyssey_2 @IABR, Tungsten Pro

Impression of the multimedia installation 2050: An Energetic Odyssey.