Floating closed cages ‘can quadruple profits’
Growing salmon in floating closed-containment plants could earn a farmer four times as much in profit over a 10-year period as they would make using open cages, according to financial experts.
The faster growth and shorter cycle, reduction of waste, and elimination of hefty lice-treatment costs that closed containment provides would vastly increase earnings, according to Knut Senstad of Inventura, which describes itself as the Nordic region's largest consultancy in purchasing and cost management.
Senstad held a lecture at the Tekmar event in Trondheim, discussing the possibilities for maximizing both the total salmon production in Norway, but also the farmer's own volume and profit, by using closed floating plants, for example in the fjords.
"I think one should use floating, closed technology where appropriate. Not everyone is going to do it, but I mean floating, closed is a way to go," he said.
He opened by pointing out that salmon has become expensive to produce in open cages.
Increasingly relevant
"[In Norway] it now costs about 40 NOK (£3.60) / kg to get the fish in the box HOG. The waste is still high, between 18-20%. The industry [in Norway] has just received the traffic light scheme, and we're guaranteed more such arrangements. This means that closed plants have become increasingly relevant," he said.
His starting point is that floating closed plants, compared with traditional net pens, provide significantly faster growth and a shorter production cycle, giving less waste and increased yield per cycle. This results in increased operating profit per generation.
Lower mortality
Senstad and colleagues have done calculations that show that a closed plant will lead to a reduced feed factor, lower mortality due to no lice treatments and a shorter fallowing period. All in all, it will provide a 5.5kg salmon in 70 weeks including fallowing. Traditional plants manage this in 83 weeks.
Thus, in 10 years, it is possible to produce 7.42 generations in the floating, closed plant, while in the open cage, only 6.27 generations can be produced.
He has calculated the overall production cost to 24.79 NOK (£2.22) / kg in a floating closed, against 31.40 NOK (£2.81) in an open cage. The largest single factor that differentiates is the treatment cost against lice, which he has set at 5.84 NOK (£0.52) / kg for net pens.
Profit almost four times higher
The figures provide a significant difference in operating margin per kilo. For the closed plant he has put it at 14.36 NOK (£1.28) / kg, against 5.15 NOK (£0.46) / kg in net pens.
Combining this with the ability to produce more fish in the closed plant, he shows that after ten years, an operating profit from the closed plant is almost four times greater than the net pens. On each generation, the operating surplus will be three times as high.
"And it's entirely possible to do better. The fish will probably grow even more. These, I think, are quite objective and correct numbers, and I have not highlighted closed systems in the calculations," he emphasised.
Very good figures
He points out that such plants have now documented very good operating figures over several generations.
"The authorities should therefore create predictability and resemblance to other concepts such as RAS facilities on land. There should be no difference in treatment. Environmental and welfare requirements must be similar, familiar and measurable."
Therefore, he believes that a quick clarification of parameters such as the maximum number of fish per unit, density up to 50 kg per cubic metre and CO2 saturation in the water is required.
There are at least four in-sea closed containment systems running in Norway: Ecomerden is active on a Sulefisk site; Neptun 3 is used on a Marine Harvest site in the west; Akvadesign has some closed systems in Brønnøysund; Preline is a closed concept developed by Lerøy, co-owner of Scottish Sea Farms.
