Norway's third-largest salmon farming company SalMar plans to start rearing fish out to sea using constructions based on oil platforms, each of which could house eight times as many salmon as conventional cages.
The company has hired Gunnar Myrebøe, who oversaw the design of the offshore rig for the Snøhvit gas field, to develop the semi-submersible platform.
The 5,600 tonne, 670-metre-high steel construction, will enclose a 245 square metre pen for the salmon, space for 600 tonnes of feed, and accommodation for up to four people.
By farming further out to sea, the company aims to reduce problems with salmon lice, and protect wild salmon from infections.
The installation will be kept in place with eight anchors, and will be able to withstand waves nine metres high, three times as large as the waves existing salmon cages can handle.