Kelp farming is on its way

Kelp cultivation will mean that we can produce bioethanol fuel in addition to biogas for heating and fuel, without the need to use food crops as a raw material, and without having to utilise agricultural land or freshwater resources.

This is among the reasons behind SINTEF's decision to establish the Norwegian Centre for Seaweed and Kelp Technology, which was opened in Trondheim on August 15 by State Secretary Kristine Gramstad of the Ministry of Fisheries and Coastal Affairs

Many areas of application

There are even more potential uses of kelp and seaweed beyond applications as sources of energy.

As well as being an energy resource, macroalgae such as kelp and seaweed are used in food production and as agents that bind water, in biological purification systems, the reestablishment of kelp cultures in fjords that have suffered high rates of kelp mortality, as soil improvers and in the hunt for new compounds for medical and industrial applications (bioprospecting).

Exciting interface

"Macroalgae cultivation lies at an exciting interface between better resource utilisation, new marine-based products and potential renewable energy production. Although the process of establishing new industry can be demanding, I believe that a maritime land such as Norway, with its major offshore and marine supply industries, solid research base and a world-beating aquaculture industry should be quite capable of achieving success in this field," says State Secretary Gramstad.

Efficiency challenges

Today, some 15 million tonnes of seaweed and kelp are cultivated all over the world, mostly in Asia, and are used in foods, animal feedstuffs, chemicals, medicines, health foods, cosmetics and fertilisers.

"The Norwegian coastline, including all its islands, is twice as long as the Equator. In other words, we possess huge areas that are suitable for cultivating seaweed and kelp. However, manpower is more expensive here than in Asia. This means that the greatest challenge lies in cultivating large volumes at sufficiently low cost, and research-based knowledge will be essentlal if we are to manage this,"says chief scientist Trina Galloway of SINTEF Fisheries and Aquaculture.

International invitations

Galloway says that SINTEF has already been cultivating kelp on a trial basis, on behalf of Norwegian industrial interests and with financial support from the the Research Council of Norway.

"We ourselves have a good deal of competence, but there are also inportant sources of knowledge elsewhere in the world. The aim of the centre is to gather all such sources of expertise into a single team, so we are inviting both Norwegian and overseas research gropups into the centre.

Could be fertilised by farmed fish

The competence centre will offer industry and the authorities its knowledge, which will cover everything from controlled production of seed plants and cultivation in the sea to harvesting and processing the raw material for a wide range of applications.

Seaweed and kelp take up nutrient salts (fertilisers) and CO₂ from the sea. The plants can be cultivated in dedicated macroalgae systems, or side by side with farmed fish. The plants can thus be fertilised by the fish and thus help to cleanse the water around the sea-cages.

From harvesting to cultivation

At present, seaweed and kelp are not cultivated commercially in Norway. But we already have a major industry based on an annual harvest of around 150,000 tonnes of kelp from which alginates are extracted. These are substances that have the ability to thicken and stabilise liquids, and are therefore used in a large number of food products. Grisetang is also used to produce kelp meal, which is used as a soil improver and in animal feed and health-food products.

"Although harvesting removes less than one percent of Norway's standing seaweed and kelp biomass, we do not recommend taking out more than this amount, as kelp forests are actually important nursery and feeding grounds for a wide range of invertebrates and fish. If we want to expand our kelp-based industry, we will have to cultivate kelp on a large scale," says Galloway.