EVN delivers vessels for sustainable offshore fish farming

Globally, the growth of coastal fish farming is limited by a number of challenges. These include discharge of antibiotics, harmful algae blooms, build-up of waste feed and faeces on the seabed, fish escapes, sea lice and transmission of disease between farmed and wild fish.

As smaller fish need to be shielded from strong ocean currents to survive, most fish farms are located near land – occupying valuable coastal areas otherwise suited for outdoor recreation and other activities.

Environmental Vision Norway (EVN) has developed the Autonomous Offshore Fish Farming Vessel, making offshore fish farming a viable alternative to coastal or land-based fish farming.

The vessel’s fish pens are equipped with uniquely constructed autonomous current deflectors that shield smaller fish from potentially deadly ocean currents, at the same time allowing bigger fish to swim deeper as they grow stronger.

By moving fish farming operations into open waters, production becomes more sustainable as stronger currents and deeper waters wash away and dilute discharged nutrients and faeces. These, like phosphorus, can then be assimilated back into the aquatic ecosystem.

The currents also significantly reduce the risk of algae bloom and contaminants associated with coastal aquaculture.

The Autonomous Offshore Fish Farming Vessel is designed for Norwegian waters, and can be anchored in unsheltered areas where fish grow faster due to naturally well-aerated water.

Furthermore, the structure of the vessel allows it to maintain full functionality in rapidly changing conditions, withstanding high waves and extreme weather with ease. This makes it suitable for use in most locations around the world, where the vessel can be customised for local weather conditions. A vessel at anchor is also easy to move from site to site.

Today, 17 per cent of the protein consumed worldwide comes from the ocean, a figure expected to rise to 40 per cent by 2050. Norwegian authorities estimate a five-fold increase in aquaculture by 2050 – while at the same time signalling stricter regulations on coastal fish farming due to environmental concerns.

By moving operations offshore, aquaculture companies can not only comply with stricter regulations, but also obtain more space – making it possible to achieve higher production in a sustainable manner. Annual production using the Autonomous Offshore Fish Farming Vessel as the fish farming facility is estimated at 8 000–10 000 metric tons.

The main markets for the vessel are Canada, Chile, Norway and Scotland.