Seaweed has been difficult to harvest efficiently on a large scale. But that could change radically in the next two years.
This month sees the partners behind AT-SEA ramping up the testing phase of the initiative that aims to prove the technical and economic feasibility of open sea cultivation of macroalgae.
Currently, seaweed is obtained by harvesting wild seaweed, mainly in Ireland and Norway, or by using rope-based cultivation, common in Asia. Neither of these approaches scale up easily as both methods require a lot of manpower and produce relatively low yields.
“In Asia, seaweed production relies on a one-dimensional rope system, which is labor intensive. In Europe, we have to employ a smarter, more optimized way of growing seaweed. The AT-SEA partners have developed three dimensional substrates for growing macroalgae that generate significantly higher algae yields and allow easy, mechanized cultivation,” project coordinator Bert Groenendaal, of Belgium-based Sioen Industries, told feednavigator.com today.
Seven companies are involved in the project including Dutch seaweed-derived salmon feed producer, Hortimare, as well as several textile producers and research centers.
Testing to demonstrate higher yields
Tests at trial sites including Solund in Norway, Oban in Scotland and Galway in Ireland have produced yields of up to 16kg of wet seaweed per square meter – three to five times the yield of traditional seaweed farming.
And the consortium is now set to start cultivating 200 square meters of mats at each of those sites.
The aim is to evaluate their potential for commercial use. Groenendaal estimated that yields could increase to 20-25 kg per square meter as the consortium refines its techniques.
“The culmination of the project's testing phase will be May or June 2015,” said the coordinator.
The substrates used by the consortium can support large numbers of seaweed plants without breaking up or attracting unwanted plants or molluscs, explained Groenendaal.
Bio-sourced coatings on the textiles protect young seaweed and boost growth. When the seaweed is fully grown, ship-based machines cut the plants from the mats and direct them to flexible storage tanks, he added.
After the project winds up next summer, the project partners plan to establish a two to three hectare cultivation site through a commercial start-up to be spun off from AT-SEA.
“The spin-off would use a profit-sharing model to benefit all the partners. However, discussions on its exact make-up are still underway.
The economic potential for seaweed is huge - we have had plenty of interest from other companies looking to get involved in the commercial phase of the initiative,” said Groenendaal.
And he stressed that seaweed, which contains significant quantities of valuable proteins, lipids, vitamins and minerals, could be the answer to the endless quest for ‘home grown’ sources of protein to reduce the EU feed and food sectors’ reliance on protein imports.