Senior researcher Sten Siikavuopio led Nofima's role in the algae feed project.
Photo: Jon-Are Berg-Jacobsen / Nofima.
Scientists in Norway have successfully developed salmon feed made from microalgae cultivated using carbon dioxide emissions from heavy industry.
The collaborative project, partly funded by a grant of NOK 93.3 million through Norway’s Green Platform program, involves three key Norwegian research institutions, Nofima, SINTEF, and UiT (The Arctic University of Norway), alongside the ferrosilicon manufacturer Finnfjord AS.
The goal is to use the 300,000 tons of CO₂ emitted annually from Finnfjord’s plant in Troms, northern Norway, to grow algae that can be used in feed for farmed salmon.
According to Nofima senior researcher Sten Siikavuopio, who led his organisation's role in the collaborative project, the algae, which are rich in essential fatty acids like DHA and EPA, have proven to be a promising alternative to traditional fish oil in aquaculture feed.
The project is part of a broader effort to reduce dependency on limited marine oil resources in aquafeed, the researchers explained via a Norwegian language press release.
“The salmon grow well on the algae feed and are in good health,” he stated, citing results from feeding trials that span the salmon’s full growth cycle.
The project partners have installed microalgae cultivation tanks at Finnfjord's smelter site, which are directly infused with CO₂ emissions from the ferrosilicon production process. The algae absorb the CO₂ and convert it into biomass rich in omega-3 fatty acids, which are critical to salmon health.
The process has already shown measurable progress, according to the research team. Initially, only 3% of the feed could consist of algae due to high water content in the biomass. However, advancements in separation technology have enabled feed formulations with up to 15% algae.
The algae-based feed is currently being tested at Flakstadvåg Laks AS, a salmon farm on the island of Senja.
"The trials so far show that the fish grow and thrive very well with a high mixture of algae in the feed," Siikavuopio said, while noting that ongoing trials are essential to determine the upper limits of algae inclusion in salmon diets, and that more microalgae species should be studied for their use in aquaculture.