New collaboration can enable fish farms in the Mareld wind farm, Sweden




12 March 2024



Freja Offshore, a joint venture between Mainstream and Hexicon, and the Norwegian company Subfarm are initiating a collaboration to enable fish farming inside the proposed 2.5 GW Mareld offshore wind farm in Swedish waters. This new initiative will take a closer look at how electricity production and the fishing industry can be combined.

Freja Offshore has applied to build the Mareld offshore wind farm, 40 kilometres west of Lysekil. The initiative aims to enable fish farms inside the wind farm. Lysekil Municipality, the research institute DHI and the Norwegian industrial cluster Blue Maritime Cluster are also involved in the collaboration.

The Västra Götaland region needs to triple its electricity production in the coming years to meet the energy demand, and offshore wind will play a key role in this. At the same time, wind power must be able to coexist with other important interests, not least the fishing industry and sea-based food production.  Therefore, Freja Offshore now wants to develop the possibility of conducting sustainable fish farms in connection with the Mareld wind farm.

“Seafood and offshore wind power are two industries that Sweden will need more of in the future, that’s why we want to find ways for these two industries to co-exist.” says Magnus Hallman, CEO of Freja Offshore.

Previous studies show that offshore wind farms can act as artificial reefs and marine protected areas. This increases the amount of fish and shellfish and, in turn, the availability of prey.

The Norwegian company Subfarm has been working since 2018 to develop solutions that enable sustainable fish farming inside offshore wind farms. The fish farms will be placed between the wind turbine platforms and they will be anchored with their own anchoring system. The fish cages will be lowered to a depth of 50-70 meters and hoisted up to the surface position for checks and harvesting. They are then transported by ship to land.

Minimising the environmental impact

“Sustainability is a common thread in everything we do. We work with technology that minimises the environmental impact and puts the well-being of the fish at the center. By co-locating with wind power, we can further reduce the ecological footprint as much of the infrastructure is already in place,” says Karl C Strømsem, Chairman of the Board of Subfarm.

The technology is designed to withstand harsh weather conditions in the North Sea and is based on methods previously used in the oil and gas industry for decades. The entire system is controlled from a control station on land.

The combination of fish farming and wind power would mean great opportunities for Lysekil municipality in terms of jobs and entrepreneurship. Construction and design of fishing gear, service vessels, fish processing and increased demand for marine technology are some examples. At the same time, the municipality is heavily dependent on increased electricity production.

“We are facing a major transition in which electrification plays a crucial role. To succeed, we need to think in new ways and see what opportunities wind power can bring to our development as a coastal municipality. That’s why it’s extra exciting to be part of this project,” says Anne Bergeld Gunnäs, Maritime Business Developer in Lysekil Municipality.

Facts about the participating parties:

  • Subfarm is one of Norway’s leading companies in offshore fish farming with a strong focus on sustainability. The company develops fishing cages that will work in the world’s harshest conditions in the North Sea.
  • Lysekil municipality is a node for knowledge and development in the marine field.
  • DHI is an international organization with 60 years of experience in studies of the oceans and the environment in 140 countries. The organisation is based in Denmark.
  • The Blue Maritime Cluster is a collaboration between 200 Norwegian actors active in marine operations. Has been granted special expert status by the Norwegian government.
  • Freja Offshore AB is a joint venture between Norwegian Mainstream Renewable Power and Swedish Hexicon, established to develop, build and operate floating offshore wind farms in Sweden.

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