With the understanding that good lighting can stimulate growth and keep farmed salmon healthy, Philips aquaculture LED lighting has been installed at Havlandet’s newly-built, land-based recirculating aquaculture system (RAS) pilot plant in Florø, Norway.
In autumn 2020, INC Group, which owns Havlandet, received €1.5 million from Innovation Norway to build the land-based RAS plant, and a licence has been granted for an annual production of 200 tonnes.
The long-term plan is to build a land-based fish farm with a large-scale production of 20-25,000 tonnes of salmon from 2026.
“Growing salmon on shore is exciting,” Havlandet’s Operations Manager Fredrik Grahl-Jacobsen said. “We want to start a full-scale production and considered it best to start with a smaller pilot plant; there are several parameters for fish welfare that we use, so this allows us to test everything first.”
Grahl-Jacobsen explained that initially only surface lights were used for the RAS plant. But it was observed that the salmon gathered close together down in the darker parts of the tank, at a depth of about three metres. “We wanted to generate more uniform light at the bottom of the tanks, as this suppresses the sexual maturation of the salmon. We therefore began to search for a supplier of underwater lights and got in touch with Signify.”
Signify is the company name of Philips Lighting.
“Maturation produces salmon that cannot be eaten. For the salmon not to go into maturation they need enough light to mimic summer conditions,” Grahl-Jacobsen said. “It has been a problem for many salmon farmers. Fish naturally perceive light differently than humans, and too much red in the light can cause more stressed salmon, and more algae to grow in the tanks.”
Using drawings of the plant, Signify provided a detailed lighting plan with calculations of its light needs, said Kristian Hoyland, Department Manager at NBN Electro, an INC Group company.
“We switched from using surface lighting only to a combination with Philips underwater lighting and a control system. With underwater light, there is more uniform light in the tank. Thanks to Philips aquaculture LED lights, we have control over the factors that affect the sex maturity of the salmon. The system allows for control of the lights and gives insights into their performance.”
The lights are on a 24-hour fixed programme, said Grahl-Jacobsen.
“The fish are growing fast, and we see that they’re healthy. There is a very low mortality rate and by growing in a RAS, we avoid salmon lice. All in all, the collaboration with Signify has worked well and we’ve had useful follow-ups. They are easy to reach and when we ask questions, we get a quick response.”
“It is crucial to avoid dark spots in the tank and so reduce stress for the salmon,” said Signify Sales Manager – Aquaculture, Steinar Grønnerud. “Based on the customer’s situation, the depth of the tank and the water quality, we will develop a lighting plan in which the light is as uniform as possible.
“Philips’s patented light spectrum has been developed specifically for salmon growth and health, providing 30% more light. In larger tanks and at a depth of more than 4.5 metres, underwater lighting should be considered as an addition to surface lighting. A light amount of 1,000 lux on the surface and a minimum of 10 lux at the bottom of the system ensures optimal distribution of the light.”
Philips’s aquaculture control system helps define different light recipes, including how much light is needed and for how long.
When the salmon receive light over longer periods, they will eat more and grow faster.
The lighting can also be dimmed down to 0.3% if needed without the lights flickering. Flickering, sudden disruptions and non-natural photoperiod behaviour are key triggers for stress responses, which increases the cortisol levels of the fish and so comprises their welfare. The control system can be connected to several tanks in the same facility, where each tank can be monitored and controlled separately.
“We are very pleased that Havlandet farm put their trust in us, and that they can now control the factors that affect sexual maturation using Philips’s LED lights and control system,” said Grønnerud.
