Finite land-based resources mean farming in productive parts of the ocean is likely to be essential if we are to meet the food, animal feed and raw material demands of a growing global population. A research project in Norway, MACROSEA, believes that developing an industrialised approach to seaweed farming will be part of the solution – and has the potential to become a significant industry in the country.
The project, which is funded by the Research Council of Norway and coordinated by SINTEF Ocean, is providing new insights into the potential of seaweed farming in Norway and developing ‘innovative solutions’ to support the large-scale commercialisation of the sector.
Norway: A future seaweed powerhouse?
The annual global production of macroalgae has now exceeded 30 million tons. The greatest volumes of macroalgae are produced in Asian countries such as China, Indonesia, Japan and Korea. Currently, the sector relies heavily on manual labour and there is little automation in the production process.
The results of the MACROSEA project suggest that all this could change. It concluded that Norway has ‘massive potential’ to cultivate a wide variety of macroalgal species along its elongated coastline.
Systematic studies of cultivation conditions, fouling, and the genetics of the brown alga sugar kelp were carried out. For the first time in Norway, the research group succeeded in growing the red alga Palmaria (also known as red dulse) in nets at sea. They have also developed algal growth models, which are linked to 3D hydrodynamic-ecosystem models, in order to estimate how seaweed production progresses under different conditions.
The results demonstrate that seaweed farming has the potential to become a major new industry in Norway.
“We have developed three equipment prototypes for seaweed cultivation, a production potential model, and a computational tool for the design of a marine seaweed farming facility,” Aleksander Handå, a research manager at SINTEF Ocean, detailed.
The researchers found that the fjords and coastline of Norway have the potential to produce about 70 tons of macroalgae per hectare, and as much as 140 tons per hectare in favourable areas. Researchers believe that in Mid-Norway alone it will be possible to cultivate of the order of 20 million tons (fresh weight) of seaweeds, which in turn results in 2 million tons of dried raw materials.
In order to achieve this, 4,000 square kilometres of sea area will be required for cultivation. In comparison, about 1.3 million tons of cereals are currently grown in Norway across an area of 2,800 square kilometres.
“If a policy is developed to cultivate seaweeds offshore, away from the coastline, the potential may be even greater," said Ole Jacob Broch, a Senior Research Scientist at SINTEF Ocean.
“We saw that the period of maximum production yield varies by up to two months as we progress from south to north along the Norwegian coast. This is good news because it shows that it is possible to deliver raw materials produced in Norway over a longer period. This makes our coastline ideal for the farming of macroalgae.”
For the country to make the most of this commercial potential Handå said investment in infrastructure and new technologies will be necessary. “Nationwide investment in an infrastructure for the development and standardisation of new technology for industrial biomass production is a prerequisite for success,” Handå suggested.
“Norway's elongated coastline, combined with an investment in research into seaweed farming, will form a solid foundation for Norway’s ability to succeed in developing seaweed farming as a commercial industry.”
Researchers believe that integrating knowledge centres with industrial companies along the entire length of the Norwegian coast will promote the establishment of ‘world-leading’ innovation clusters and accelerate relevant research both in Norway and around the world.
Food, feed and more
Seaweed is gaining popularity as a food ingredient as the food sector continues to seek out alternative sources of plant-based protein.
According to a report from the European Commission, released last year, the production of global products containing ingredients from seaweeds has risen regularly since 2011, with 4% growth reported between 2014 and 2015. Meanwhile, research provider Innova Market Insights reports a 10% increase in launches of global supplements containing seaweed ingredients.
Seaweed offers an appealing nutritional profile. While content varies between species, seaweed features a high protein and mineral content, including iodine, magnesium, calcium, riboflavin, folate, iron and potassium. It is a good source of vitamins A, C, E and K and is typically rich in fibre and polyunsaturated fatty acids (omega-3 and omega-6). Certain varieties are also able to act as clean label food colourings.
Silje Forbord SINTEF researcher, said that for every 20m tons of seaweed, 100,000 tons of protein can be extracted.
Seaweed may be able to offer the ‘same applications’ as soya and oil and while food is currently the seaweed industry’s main focus, the researchers see potential uses stretching way beyond this.
“Currently, it is mainly only the cultivation of seaweeds for food that is profitable. However, the development of new technologies for large-scale biomass production may change this,” Handå predicted. “In the coming decades, the world will be demanding more animal feed and large volumes of renewable raw materials. The industrial production of seaweed may then become part of the solution.”
Forbord added that seaweed could also be leveraged as a sustainable material in the future: “The idea of replacing oil-based plastic with an eco-friendly, seaweed-based plastic is very interesting. However, other coveted constituents of macroalgae such as antioxidants, proteins and suchlike are also interesting.”
She believes that, in addition to the manufacture of clothing, food packaging, biodegradable bottles and other products made from seaweeds, more work has to be done on the development of other climate-friendly, seaweed-based products, as substitutes for those currently based on raw materials such as oil and soya.
Maximising sustainable cultivation
In order to maximise the environmental impact of seaweed cultivation, a new and ‘standardised technology’ must be developed, the research project concluded. There is also a need to upscale cultivation in the form of major industrial-scale farm facilities located further out to sea.
Seaweed cultivation has the potential to contribute to carbon dioxide capture. By binding CO2 in the water through photosynthesis, it is possible to leverage seaweed farming to capture the greenhouse gas from the atmosphere, the researchers revealed.
“If the macroalgal raw materials are used in products whose manufacture is currently based on materials derived from fossil fuels, this will also reduce greenhouse emissions.”
When parts of the seaweed blades – which contain CO2 – flake off and sink to the sea floor, they may provide food for benthic organisms and also combine with the bottom sediments, storing carbon at the bottom of the ocean.
By dumping the biomass at ‘great depths’ or using it to make biocoal, it is possible to make an active contribution towards reducing the concentration of CO2 in the atmosphere, the researchers found. The cultivation of 20 million tonnes of seaweed can bind about four million tonnes of CO2, they noted.
“The industrial scale production of macroalgae may prove to be a major contributor to innovative and climate-friendly solutions, a green transition and the movement towards a low-emissions society, thus helping us to meet the targets set by the Paris Agreement,” Handå concluded.