The Natural Resources Institute Finland (Luke) has developed a container-based fish farming concept, a cost-efficient option for environmentally friendly fish farming that now starts to achieves its goal: to implement this technology across the world. The Partial air-driven Recirculation Aquaculture System (PaRAS) that offers solutions for various challenges in recirculating fish farming now has its first startup company, PaRAS Aqua, that commercializes fish farming research. The food technology fund Nordic Foodtech VC is the lead investor for the startup.
“Consumers’ demand for fish is increasing at an annual rate of 5–7 per cent. As the scope of marine fishery cannot be increased to any significant extent, fish farming is the only answer to growing demand. PaRAS solves many problems associated with recirculation aquaculture systems (RAS) and enables production to be more competitive than at present,” said Tapio Kiuru, Senior Aquaculture Expert, who will transfer from Luke to PaRAS Aqua.
The new modular and lighter RAS technology has already attracted broad interest both nationally and internationally. As Finland’s most recent farm projects have been based on foreign technologies, a Finnish company offering Finnish technology is more than welcome to the market.
“Our goal is to become a major international player, but we will start by gaining a foothold in Finland because here we have the home-field advantage. However, internationalization is vital for our company,” Kiuru added.
A giant leap forward
“We are really pleased to pave the way for this innovation. Currently fish is in high demand and also highly nutritious, but growing it at sea is not without problems from an environmental point of view. A recirculation aquaculture solution minimizes environmental impact, and the PaRAS concept carries the RAS technology significant leaps forward,” said for his part Pekka Siivonen-Uotila, from Nordic Foodtech, the lead investor for the startup.
Luke’s container-based fish farming concept has undergone further development, and the new concept is expected to improve energy efficiency and production capacity. In the second-generation prototype, the tank size can be scaled according to the needs of fish farms of all sizes.
“The Partial air-driven Recirculation Aquaculture System concept has been tested for two years with excellent results. Compared to recirculating fish farming, the concept’s advantages include improved fish growth and a more predictable product quality, as well as lower investment and operating costs,” says Kiuru, principal specialist at Luke.
A single 12-metre container
While shipping containers continue to be an integral part of the concept, now a single 12-metre container carries elements for two 96 m3 tanks to the installation site, whereas the volume of the original container-based tank delivered as a complete system was only 50 m3.
The element-based tank assembled using bolt joints is quick to install, and the elements include all the water treatment technology required. The new concept also operates mixed-cell principle, in which the size of a single water treatment cell is 32 m3. Any number of these cells can be joined together according to needs. A three-cell tank with a volume of 96 m3 is being tested at Luke’s facility in Laukaa during the 2022 farming season.
Reproducing the modular concept produces savings in design, component and procurement, as well as plant set-up costs.
Environmentally friendly option
PaRAS tanks are ready-to-use partial recirculation aquaculture systems. The partial recirculation concept uses slightly more water than a recirculation aquaculture system. However, for the experts of Luke, partial recirculation is a significantly simpler and an often more affordable option for environmentally friendly fish farming than recirculation aquaculture systems.
The higher savings and the simpler management of water quality can be explained by partial circulation systems not having any bioreactors that carry high investment costs and maintenance of microbiological processes, they explain. This also reduces operating costs, as bioreactors consume high amounts of oxygen and require uninterrupted chemical pH adjustments.
Furthermore, bioreactors release compounds that affect the taste of fish. These effects can be eliminated by means of freshening, but the high costs of freshening solutions are among key challenges in recirculating fish farming.
According to the professionals of Luke, the new design improves the concept’s energy efficiency and production capacity. “Measured data can only be obtained after the trials conducted during the 2022 farming season, but we have already seen during the first part of the experiment that the maximum feeding in the 96 m3 PaRAS system is much higher than 100 kg a day. If operated round the year, the annual production of a tank of this size could easily be around 25 tons, which is significantly higher than the production capacity of current recirculation farms relative to the tank volume,” Kiuru said.