Mowi to "almost double" closed containment sea facilities in Norway

Mowi says it plans to almost double its capacity in closed sea cages over the next year, building on more than a decade of work with the technology, the company confirmed in an update published on its website this week.

The move comes in the wake of the Norwegian government’s introduction in October of an environmental technology incentive scheme designed to enable farmers to regain previously withdrawn biomass licences in red zones of the country’s traffic light system, as long as the fish are raised in closed systems that meet specific environmental standards.

Mowi already operates an aquaculture site at Slåttenes in Vestland that uses only closed systems. The company says it was the first operator in Norway to deploy this technology on a large scale, starting in 2013, initially as a research and development project. Since then, capacity has been built up gradually.

According to figures from the analysis firm Kontali, Mowi currently operates around 170,000 cubic metres of closed cage volume, representing more than one third of Norway’s total capacity in this segment. Based on these calculations, the company describes itself as the largest operator of closed cages globally.

Mowi's renewed emphasis on closed systems - as with other major players in Norway - can be seen as a response to changes in Norwegian aquaculture policy. In November, the company reported that 10.5 of its licences had been revoked under the traffic light framework.

However, in its update on its adoption of closed containment technology published this month, Mowi argued its increased focus on the technology is also closely linked to its post-smolt strategy.

Farmed salmon typically enter the sea at a weight of about 150 grams, but the company says keeping fish in land-based tanks or closed cages until they reach around 700 grams can shorten the time spent in open sea cages. Mowi argues that this reduces the need for lice treatments and improves survival rates.

The company confirmed it has ordered four closed cages from FiiZK and one from Fishglobe Technologies, in addition to the six units it already has in operation, with deliveries expected during 2026 and 2027. Once all 11 units are in use, Mowi says total closed cage volume at sea will rise to about 320,000 cubic metres, close to doubling its current closed capacity.

Mowi said it expects the strategy to improve licence utilisation and fish welfare over time. It also projects that post-smolt will account for about 40% of its production nationwide in Norway, and 60% south of Namsos, by the end of 2026.

However, the company acknowledged that closed technology still plays a limited role in overall salmon production. Total closed cage capacity in Norway is estimated to correspond to only 24 traditional open cages, or the output of roughly two to three conventional farms.

“More experience, development and optimization are needed before the closed technology at sea can be used on a larger scale. It is still largely a matter of a supplement to post-smolt production on land,” said Øyvind Oaland, COO of Mowi Norway, in a statement published on the company's website.

He added that wider adoption is limited by partly immature technology, a small supplier market, challenges in terms of costs, and limited access to infrastructure such as electricity. “We need a framework that is predictable and stimulates development and enables the use of new solutions and technologies throughout the country,” Oaland argued.