The new salmon cage being tested here will be both dynamic and completely automatic, while at the same time preventing salmon lice from spreading, and farmed fish from escaping. There are thus strong demands on this cover that keeps the fish in place and lice at bay.
The prototype has a diameter of 20 metres. Ocean equipment supplier Nekkar is behind the cage project, which has been dubbed “Starfish”. Since March 2021 the cage has been splashing around in Norwegian weather conditions and wind in the ocean off the Flekkefjord. Nekkar is working closely with various relevant experts, including aquaculture company Lerøy.
Stricter environmental demands
An important part of the solution is the cover that will be used both as an underwater bag and as a cover over the cage itself. The cover must not only prevent the fish from escaping, but also fulfil a range of strict performance and environmental demands.
Protan has over 80 years of experience in the production of membranes and technical textiles for a range of purposes and has now developed a series of innovative and completely recyclable PVC covers – Protan BlueSafe – that will help the aquaculture industry solve many types of environmental challenges.
If the Starfish project is as successful as expected, this will represent an international breakthrough for the fish farming industry, for which sustainability is high on the agenda. Already in the Canadian province of British Columbia, it will be a legal requirement for all salmon cages to be closed from 2025.
Protan BlueSafe – special cover for ocean use
Protan started developing covers and systems for the storage and transport of fresh water already in the early 2000s. These covers and systems were, for example, used in desert areas in the Arabian Peninsula. The same technology and innovative approach are being used in special products for the oil and gas industry and for a range of other purposes.
For the Starfish project, Protan has developed a completely new cover quality for its BlueSafe series with extreme characteristics. The cover is of symetricon quality and extremely dimensionally stable. Its durability is unsurpassed. The cover has undergone stringent cyclical tests at SINTEF, Norway’s (Norwegian technology and innovation research institute).
Protan has designed the new cover together with clients to obtain the best possible performance according to their specifications. This is the typical way that Protan works. We strive to use all the cutting-edge expertise in our company in close cooperation with our clients to find the optimal solutions for their requirements and challenges. Our PVC technology is both flexible and sustainable.
Environmentally friendly installation and materials
In addition to the quality of our PVC covers, cage solutions such as Starfish require competence in assembly, installation and logistics. Assembly takes place at the Protan factory in Nesbyen, Norway. Expert roofers from Protan don life jackets and weld the membrane joints out on the cage itself. They do this using hot air and electricity – a completely emissions-free installation method. In addition, eyelets and loops are mounted for easier attachment and installation.
Protan BlueSafe covers have many more uses than for closed cage systems and lice skirts. They are also used in artificial seaweed forests or as a lining for breeding vessels and in old and new tanks for juvenile and cleaner fish.