A pioneering commercial-scale seaweed farming operation is active 18 kilometres off the Dutch coast. The Hollandse Kust Zuid (HKZ) venture is located between wind turbines where seaweed production can be tested and improved. In parallel, scientific research aims to validate the carbon sequestration potential of seaweed farms and measure biodiversity impacts.
North Sea Farmers (NSF) states that in the North Sea, offshore seaweed cultivation has only be done in the form of research pilots – but to understand what makes a viable and scalable business model and what the impacts are on the environment, the intention os to for a commercially operated seaweed farm, including onshore processing activities.
‘Through ongoing scientific research, we am to demonstrate whether farms like this can have a positive long-term impact on both biodiversity and climate change mitigation,’ said NSF managing director Eef Brouwers.
‘At the same time, we’re proving that seaweed production within an existing offshore infrastructure is possible at a commercial scale.’
The project was conceived in 2022 and the first seaweed was planted in October 2024.
The installation covers a five-hectare space, with four 50×3-metre nets anchored in position to cultivate and gather mature seaweed.
According to NSF, seaweed can be used to produce a variety of textiles and foodstuffs, and can be used to replace a number of products cultivated on land using chemicals – while seaweed does not require land, fresh water of fertilisers.
Researchers from Plymouth Marine Laboratory, Deltares and Silvestrum Climate Associates have been monitoring the location over the last year, through both site visits and satellite imagery.
The aim is for the research partners to deliver a comprehensive analysis of seaeed groth, carbon absorption rates, overall carbons torage and potential effects on wildlife.
‘We’re very excited to understand the effects of the seaweed farm on the immediate and surrounding marine environment. Our analysis will follow the carbon from the sea water into the seaweed and the environment, and any effects on biodiversity,’ said professor Ana M Queirós of Plymouth Marine Laboratory.
‘Its vital that projects like this are underpinned with rigorous scientific evidence, particularly given the urgency of the climate and biodiversity crisis and the need to find scalable mitigation measures that produce genuinely beneficial outcomes.’
