The Crown Estate and Cefas advance understanding of interactions between offshore subsea power cables and marine environment

The Crown Estate and the Centre for Environment, Fisheries and Aquaculture Science (Cefas) have today published a report which aims to help stakeholders involved in offshore wind developments better assess the impacts of electromagnetic fields (EMFs) from subsea power cables on the marine environment.

The report, delivered in collaboration with the Scottish Government, represents the first of four Cefas-led collaborative projects being supported through £1.4m funding from The Crown Estate via the Offshore Wind Evidence and Change Programme (OWEC) – a programme led by The Crown Estate in partnership with DESNZ and Defra that is generating new data and evidence to support and accelerate the sustainable development of offshore wind in the UK.

The report will lead to an improved understanding of the potential effects of EMFs – produced by power transmitted through subsea cables - on marine species, providing further evidence to facilitate and accelerate decisions in the planning and consenting of offshore wind
developments. It is the result of a two-day workshop, organised by Cefas and the Scottish Government, which brought together 15 leading scientific minds on EMFs from across a variety of fields, including electrical engineers, oceanographers, (geo)physicists and biologists to share knowledge and set out priority actions to improve future processes.

The report ‘Electromagnetic Fields (EMFs) from subsea power cables in the natural marine environment’ can be downloaded here and includes:

1.  A summary of the aims and objectives from the workshop
2. A breakdown of methods for calculating, modelling, and measuring EMFs emitted by subsea cables
3. A summary of methodologies for measuring the impacts of EMFs on marine life
4. Short and longer-term recommendations for how to improve and standardise research in this field to allow greater sharing of data and evidence
5. Recommendations for future research in this field

These insights will feed directly into a follow-on project, funded by OWEC, named ‘Floating Offshore Wind Environmental Response to Stressors (FLOWERS)’, which will build understanding of EMF as an environmental stressor associated with floating offshore wind.

The Crown Estate has committed a total investment of up to £50 million to the OWEC programme and brings together a coalition of 27 government organisations, industry bodies, and environmental NGOs to support a range of projects that will create a data and evidence base that can be used to shape the future of offshore wind and the marine environment.

The programme is an example of The Crown Estate’s commitment to collaborate with and support the fishing industry and communities through research and engagement, enabling better coexistence between fish, fisheries, and the growing offshore wind sector across the UK.

Olivia Thomas, Head of Marine Planning at The Crown Estate said: “The UK’s offshore wind champion, Tim Pick, highlighted that a lack of reliable data is a major contributor to delays in the consenting process, which is why the work of the £50million Offshore Wind Evidence and Change (OWEC) programme is so important.

“Through OWEC, we are delighted to have invested £1.4 million to make this pioneering research possible. It contributes to a growing body of evidence to support the co-existence of vital industries such as fishing and offshore wind, to help the UK meet its net zero targets, and
to encourage a thriving marine environment. It is another step forward in building a sustainable offshore wind industry in the UK which is based on the very best data and evidence, for the benefit of all.”

Grant Stentiford, Chief Scientist at Cefas, said: “We are delighted that The Crown Estate’s Offshore Wind Evidence and Change Programme has awarded these projects to consortia led by Cefas. Offshore wind has a vital role in the UK’s transition towards clean energy and delivering on its net zero commitments, however there is still a lot we don’t know in terms of the impacts of offshore wind infrastructure on the marine environment, which can often delay progress. The results of these projects will make a significant contribution to furthering the scientific evidence base on key topics relating to biodiversity change and environmental impacts, which in turn will strengthen and improve decision making. Through this funding, Cefas will continue to work with the UK and Scottish Governments to ensure that offshore wind developments are delivered sustainability and in harmony with people and the marine environment”.

In total, four Cefas-led projects have been funded by OWEC, in a bid to build understanding of the interaction between offshore wind infrastructure and marine species. In addition to the EMF workshop, three further projects are currently underway:

• Nature Inclusive Cable Enhancement and protection (NICE) - making infrastructure work for biodiversity: The hard cable protection systems used to protect offshore wind subsea cabling provide structures that can be colonised over time by marine species, such as soft corals, mussels, crabs, lobsters, starfish and fish. The project, led in partnership with ARC Marine, will collect evidence to support the coexistence of marine life and offshore wind cabling and cable protection systems, to support offshore environmental net gain. The project will research the potential for specific cable protection designs to support and enhance seabed-associated communities, whilst also protecting subsea cabling infrastructure.

• Fisheries Sensitivity Mapping and Displacement Modelling (FiSMaDiM) – understanding how offshore wind development impacts fisheries: To understand how the development of offshore wind farms impact fishing activity, Cefas, the Marine
Directorate of the Scottish Government and University of St Andrews have been working with the National Federation of Fisherman’s Organisations and Scottish Fisherman’s Federation on an initiative to map current fishing activity and understand the economic outcomes that might be affected by displacement following the construction of offshore wind farms in Scottish waters. The investment from the Offshore Evidence and Change Programme will allow Cefas to extend the project beyond Scotland to the rest of the UK, to build up a bank of data that will help understand and manage fishing industry displacement that could occur from the development of offshore wind in key areas.

• Floating Offshore Wind Environmental Response to Stressors (FLOWERS) - understanding little known environmental impacts of floating wind: The project has three elements. The first will use modelling software to increase understanding of how
floating offshore wind moorings affect the seabed. The second, delivered in collaboration with the Scottish Government’s Marine Directorate, will apply the approach set out in the EMF technical workshop report to floating power cables. Finally, a framework for assessing multiple stressors together will be developed to help move away from single stressor-single receptor assessments.