‘Astrid Helene’ is a fully electric salmon farm workboat designed and built by Grovfjord Mekaniske Verksted, Norway. Owner/ operator Northern Lights Salmon saves the planet from up to 90t CO2 and 900kg of NOx particles annually – the average emission of a diesel powered fish-farm workboat.
There are no longer any diesel fumes on deck either. For crew, the fumes could be quite annoying – particularly if the wind was blowing it in their direction. Now, there is just clean air.
Fully electric work boats such as Astrid Helene will play a key role in the industry’s future: “Electric work boats are perfect for fish farming. The lack of engine noise is not only an advantage for the crew, but also for the salmon. It actually reduces stress levels in the fish. And the environmental benefits are obvious. This is key for us. Our aim has always been to run our business in as green a way as possible.” Explained Søren Balteskard, Chairman of Northern Lights Salmon.
The disadvantages? According to Søren Balteskard there really aren’t any. Electric boats are easy to manoeuvre and go from zero to full speed extremely fast. And the typical concern about lack of charging possibilities during long distance sailing, is not a problem as fish farms are located close to shore.
“We can use Astrid Helene for a whole workday and still have about 45 percent power left when we return to shore. Charging is easy, too. We simply plug her to the grid overnight. And the next morning, she is fully charged – at only a fraction of what it costs to fill up the tank in one of our diesel boats.”
Grovfjord Mekaniske Verksted, which designed and built Astrid Helene, is Norway’s leading manufacturer of aluminium workboats. The company has delivered more than 115 boats to the fish farm industry over the last 15 years. Astrid Helene is their first fully electric one. Others will soon follow, though. The company already has orders for another handful on the books.
The catamaran hull is very efficient and needs only a few kilowatts to glide through the water and reach speeds up to 6-7 knots. The energy demand increases exponentially at speeds above 10 knots. Consequently, the range of the vessel is dependent on speed, wind and currents, and the advanced EMS system gives the boat operator a good overview of these factors. A single charge can keep the vessel running throughout a long work day on the fish farm. When the vessel needs to traverse a longer stretch of water, a regular diesel generator can be hoisted onto the deck and connected directly to the charging plug. And just like that, Astrid Helene is transformed into a hybrid long-range boat.
Anders Breines, Lead Electrical Engineer at Grovfjord Mekaniske Verksted, says: “The drives are really key components. All electricity – every single kilowatt used on the boat – passes through them. And we are not only talking electricity for the propulsion motors, but for all electric equipment – all the way down to the coffee machine.”
Astrid Helene is packed with heavy equipment, including a 32t crane and an electric winch hauling nets that can hold 12t of salmon. Still, it moves silently through the water at up to 10 knots. Three types of components make it happen: A 4m3 big lithium-ion battery-pack, two electrical propulsion motors, and seven drives.
Drives are key components for the functionality of the vessel. Seven Vacon® NXP drives control the flow of energy between batteries, motors, chargers and power in the cabin. Two batteries from Corvus Orca generate a total of 440kWh, supplying all power on board. Two 107kW permanent-magnet motors ensure that propulsion is silent and efficient. They are also powered by Vacon® NXP drives.
Charging from onshore is controlled by a Vacon® NXP Grid Converter, and the batteries are managed by a Vacon® NXP DC/DC Converter. Even the hydraulics for the crane are run by the Vacon® NXP drive so they can be powered by the batteries. The overall control system, known as the Energy Management System (EMS), was developed by teachers and students at the University of Tromsø.
