Following the first tests of industrial prototypes, the European Union (EU)-funded Biogears project has concluded that it is possible to manufacture bio-strings for mussel and algae culture as an innovative solution for environmentally friendly offshore aquaculture. The initiative aims to provide Europe’s aquaculture sector with bio-based ropes that contribute to a more sustainable activity.
Launched in 2019, the Biogears consortium is developing prototype bio-based ropes for use in mussel and seaweed culture based on knowledge generated by previous projects. Also partly funded by the EU, these projects have been instrumental in understanding both the volume and type of marine litter generated by aquaculture and its impact on the marine environment, as well as the growth, production yield and quality of mussels when cultured on conventional plastic ropes.
Biogears uses an Integrated Multi-Trophic Aquaculture (IMTA) approach by integrating seaweed with mussel production, which aims to increase aquaculture marketable products.
Part of EU’s blue economy, offshore aquaculture is a promising sector, fostering economic opportunity, employment and food security. In offshore mussels farms, mussels are grown on long ropes, suspended underwater. However, the ropes used in aquaculture are made from plastic, threatening marine ecosystems, if discarded or not disposed of correctly.
“At the same time, as the aquaculture sector experience increasing demand, more ropes are needed.”
Aiming to replace or complement oil-based plastics, the consortium has produced compostable plastics from natural components derived from renewable biomass. The goal is to obtain a plastic that does not decompose at sea, but instead turns into compost, when it is no longer of use.
The bio-based ropes developed by Biogears are tested at sea, under different environmental conditions. Technical, environmental and economic sustainability assessment of the bio-gears is carried out, including its degradability at sea and the composting conditions.
“From the first industrial prototyping trials, we now know that it is possible to manufacture bio-gears as an innovative solution for an eco-friendly offshore aquaculture sector in Europe. It is exciting to see that we are making the change possible,” says Leire Arantzamendi Egiguren, the project coordinator.
“Arantzamendi works for AZTI, and she says that their first net prototype developed with Biogears “contains bioplastic materials of natural origin”.“
According to her, it makes them biodegradable, and they can thus be “more environmentally friendly and can provide added value to the sector”.

Commitment throughout the value chain
The project is engaging with the entire value chain and key stakeholders, from the aquaculture industry and producers of materials to regulatory authorities, policy makers, research institutions and consumers.
Beyond this project based in Mutriku, northern Spain, explain the researchers, the bio-based ropes can be adapted for other aquaculture and fisheries needs, contributing more widely to the sustainable transformation of the sector.
Biogears has three main objectives: a positive impact on sustainability of the aquaculture industry by developing more eco-friendly ropes and aquaculture systems; a positive economic impact by supporting a circular economy, through the development of new bio-based products and value chains; and a societal impact by supporting public policies to reduce plastic littering at sea, by fostering new employment, quality products and responsible production and consumption.
The EU-funded BIOGEARS projects is in line with the vision for a sustainable blue economy under the European Green Deal and contributes to European policies on plastics and microplastics. It also underpins other key policies such as those set out in the EU’s Bioeconomy Strategy and the European Farm to Fork Strategy.
Blue Lab
A Blue Lab has been created as part of the BIOGEARS project and this concept works at the interface between research and commercial exploitation, testing and piloting innovative products and services so that research results are brought closer to market.
In which targeted dissemination to relevant stakeholder will take place, increasing the likelihood of biogears reaching relevant actors and becoming established in the market. Over the last year BIOGEARS partners have engaged with stakeholders throughout various meetings and collaborations, this is set to continue in 2022.