Clean energy, fresh mussels: Scandinavia’s experiment to harvest seafood and wind power together

24.06.2024 - 21:29 / euronews.com

In a small boat bobbing in the waves between towering offshore windturbines, researchers in Europe’s Baltic Sea reach into the frigid water and remove long lines stretched between the pylons onto which mussels and seaweed are growing.

It’s part of efforts to explore multiple uses for remote wind parks far out at sea, such as fresh seafood production.

Run by the Swedish state-owned power firm Vattenfall and Denmark’s Aarhus University, the four-year project started in 2023 off the Danish east coast at Scandinavia’s largest wind farm, Kriegers Flak. With its first harvest just 18 months later, it’s already showing signs of early success.

“There’s an increasing competition for space on land and in the sea,” says Aarhus University senior scientist Annette Bruhn, who leads the project. “We can, in one area, produce both fossil-free energy and food for a growing population.”

With a capacity of over 600 megawatts, Kriegers Flak can power up to 600,000 households. Its 72 turbines deliver clean energy to nearby Denmark and Germany to the south.

But researchers saw other potential within the park’s 132 square kilometre area.

The water between its spinning blades has been transformed into an experimental underwater seafood farm.

Four hundred-meter lines spread between the turbines grow seaweed and mussel crops. The seaweed was recently harvested for the first time.

“Seaweed and mussels are low trophic aquaculture crops, which means that they can be produced without the use of fertilisers. They take up nutrients from the sea and produce healthy foods,” Bruhn says.

Recent Aarhus University modelling suggests tonnes of fresh seafood could be produced annually by utilising just a tenth of Denmark’s wind park area. Researchers say the benefits could go well beyond food production - mussel and seaweed crops could help improve water quality and capture carbon.

“These are non-fed crops that live from what they take up from the sea, they capture emissions instead of having emissions,” Bruhn says.

Researchers say now is the time to develop guidelines to encourage companies to plan for multiple uses of the ocean as European nations massively ramp up production of clean energy from wind turbines in the North Sea.

In 1991, Denmark became the first country in the world to install a commercial offshore wind park. More than 30 years later, nearly half of the Danish electricity production derives from wind turbines.

Driven to meet climate targets and reduce energy dependence on Russia, nine European countries, including Denmark, last year announced plans to quadruple current production to 120 gigawatts by the end of the decade and move to 300 gigawatts by 2050.

Vattenfall bioscience expert Tim Wilms says there’s “huge potential. We have so