Context

For ORE projects to be best integrated into the marine environment, it is important to know the interactions between these new types of infrastructures and coastal marine ecosystems. Within the framework of calls for tenders issued by the French government for the installation and operation of offshore wind farms, the question of the impact of subsea power cables is regularly raised during the consultation phases. This is also a point that is carefully examined by the environmental authority that assesses the regulatory impact studies of wind power projects. Although the direct impacts of electromagnetic fields and temperature emitted by cables are often considered to be low within the community of scientific experts, there is nevertheless a lack of data from environmental monitoring of existing projects to address these issues.

Objective

To enhance knowledge of the potential impacts of ORE electric power cables on coastal ecosystems.

Main Achievements

• In situ characterisation of changes in electromagnetic fields and temperature
• Experimental and in situ characterisation of the impact of power cables on the benthos
• Assessment of the reef effect of submarine cables and associated structures
• Drafting of recommendations for future impact assessments

Conclusion

During the project, no drastic negative impact of subsea power cables on benthic ecosystems was found. However, the research effort initiated must be continued as certain issues remain insufficiently documented. The project was a real opportunity to develop and test tools for measuring electromagnetic fields at sea. It has also permitted to propose sampling and experimentation protocols and to formulate clear and effective recommendations for studying the effect of power cables on the invertebrate communities living on soft or rocky seabeds. These are summarised in a public report that will enable the industry to adopt appropriate management measures.

Resources

SPECIES fact sheet (PDF)

Synthesis report (PDF)

Partners and funding

This project was led by Ifremer and France Energies Marines.

The total project budget was €1,025K.

This project received funding from France Energies Marines and its members and partners, as well as French State funding managed by the National Research Agency under the Investments for the Future Programme (ANR-10-IEED-0006-17).

Photo credit: Olivier Dugornay, Ifremer