• Ivana

H2020 UNITED - Belgian Pilot update: First successful installation of a seaweed farm within an offshore wind farm

The end of the year 2022 was celebrated by our Belgian Pilot Team of the H2020 project UNITED winning the Blue Innovation Swell Award 2022 and successfully installing the offshore seaweed farm within the offshore wind farm Belwind (operated by Parkwind) - 46 km off the coast of Belgium. This marks the first time a seaweed farm has been installed within an operating wind farm. The Belgian Pilot of the UNITED project investigates the feasibility of combined aquaculture and reef restoration of European flat oyster (Ostrea edulis) with cultivation of the brown macroalga sugar kelp (Saccharina latissima) in offshore wind farms.
Two years have passed during which the Belgian UNITED Team has gained valuable information and experience to successfully cultivate sugar kelp in highly exposed conditions to identify suitable cultivation methods for commercial offshore seaweed farming – the cultivation within an offshore wind farm. Prior to the installation, chosen substrates that proofed suitable in the nearshore cultivation trials, conducted over the last two years, were seeded with juvenile sugar kelp (Figure 1a) and incubated at our seaweed nursery at the Marine Station Ostend. The nursery allows for strong attachment and development of the small sugar kelp juveniles (Figure 1b) before they are installed at the highly exposed offshore test site. Just before the installation, additional substrates were seeded via an improved direct seeding method, where the seaweed juveniles are seeded onto the substrates and covered by a specific seaweed glue in the attempt to skip the nursery period and allow for direct installation after the seeding.

Figure 1: Juvenile sugar kelp (Saccharina latissima) grown at the UGent Phycology group for the offshore cultivation trials (a) and developed sugar kelp growing on cultivation substrates before installation at sea (b)

After a period of stormy weather, a suitable window finally opened mid-December to attempt the installation of the seaweed substrates. On the 12th of December the Belgian UNITED team, consisting of partners from UGent Phycology, Brevisco and Parkwind, sailed out with the team from ONDINE – an Irish shipping company specialised in providing offshore surveys – to install the next generation of seaweed within the offshore test farm of the Belgian Pilot. The operation benefited from the extensive experience of the Belgian Pilot Team and the crew from Ondine resulting in a smooth installation of the first seaweed farm within an operating offshore wind farm (Figure 2).

Picture 2
Figure 2: Installed seaweed farm within the Belgian Pilot offshore test site in the wind farm Belwind

The growth of the new generation of seaweeds being monitored until the planned harvest in late spring. Our team is especially curious about the growth performance of sugar kelp in this highly dynamic and exposed environment in comparison to the results achieved at the nearshore cultivation site, where seaweed cultivation trials were performed during the last two years.