Scientists at Plymouth Marine Laboratory (PML) in the UK are investigating the potential benefits of farming seaweed alongside offshore wind arrays.
PML said seaweed is known to absorb large quantities of CO2 but the extent of its viability for carbon removal on an industrial scale is yet to be determined. For "blue carbon" ecosystems such as mangroves, seagrasses, or salt marshes, carbon is sequestered into mud or sediment in the immediate environment – as the plants grow and die, their decomposing matter is absorbed into the ground below.
By contrast, seaweeds grow in rocky and exposed areas, making the carbon sequestration process much more difficult to track as the seaweed detritus is constantly released into the ocean, sequestering at sites on the seafloor and at unknown locations in the deep ocean.
As part of a €1.5 million (US$1.6 million) project, a team of scientists from PML is seeking to establish the role offshore seaweed farming could play in capturing and storing carbon in future. Delivered alongside North Sea Farmers (NSF), an international not-for-profit seaweed farming membership organisation, North Sea Farm 1 is a first-of-its-kind seaweed farm located amongst offshore wind turbines.
PML hopes that the project will enable a far greater understanding of the natural processes involved in the seaweed carbon cycle and the ability to track detritus and locate where carbon may be stored for the long term, in the deep ocean and seafloor.
During its first year of operation, Sea Farm 1 will focus on testing and improving the farm's production performance. The farm will make the most of the space between wind turbines.
PML said that, if successful, the project could be scaled across the North Sea, which has an estimated one million hectares of space available within existing wind farms.
Other partners involved in the project include Deltares and Silvestrum Climate Associates, seaweed product manufacturer Algaia, and maritime contractor Van Oord.