The batteries, which have been recently installed at a salmon site off the island of Selsøyvær, are projected to reduce the use of diesel generators by up to 60 percent.
The energy storage system, developed by Tesvolt, has a total storage capacity of 158 kilowatt hours (kWh) and have brought the diesel generators’ operating time down from 24 hours each day to just three.
According to Tesvolt, the installation means that the salmon producer will save between €150,000 and €200,000 for every 18-month grow-out cycle, as well as reduce their carbon footprint.
Tesvolt worked together with Norwegian partner company Kverneland Energi to develop, deliver and install the battery system in accordance with the fish farm’s requirements.
Kvarøy, a third-generation family-run company, has taken it upon itself to run its fish farm sustainably. A major factor in implementing this policy was reducing the high rates of diesel consumption for operating the fish farm and the feeding systems. Two large and one small diesel generators are in operation on their feed barges and at least one of them must always be running, since there is no mains power connection.
At the same time, the electricity demand fluctuates greatly within the course of a day — at feeding times, the systems require a lot of energy, whereas at other times, only the light on the barge is on. Due to long operating periods and poor diesel combustion in the generators, each kilowatt hour of electricity brought with it considerable costs.
Additionally, a large portion of the diesel was only used to keep the engine warm while a small portion actually drove the system. On top of that, the fuel has to be transported by boat to the salmon farm, which of course means additional energy and incurred costs.
In order to avoid the worst of these problems Tesvolt and Kverneland Energi came up with a special battery system solution. With its 120 kW peak power capacity, the battery system can be monitored and controlled from land over the internet. Power electronics from Siemens control all energy flows on the working platform fully autonomously and deliver electricity to all consuming elements. A diesel generator creates electricity for the batteries at full capacity operation and the electrical energy consumers are supplied by the batteries with the necessary electricity. The generator is not switched on and the batteries are not recharged until the state of charge is low. The battery system allows for a reduction in the fish farm’s total diesel consumption of up to 60 percent.
“Tesvolt battery storage systems are the only ones on the market that can be fully charged and discharged twice in one day and still maintain their long service life,” Jonas A Kverneland, technical director of Kverneland Energi, explains in a news release.
“Many suppliers only enable one storage system charge and discharge cycle per day, which wouldn’t have worked for the salmon farm.”
A further advantage is that the Kvarøy team now only needs to change the diesel generators’ oil biannually instead of monthly. Given that an oil change takes an entire day and costs up to €1,000. That means that the company now saves ten working days and €10,000 euros each year in oil changes alone.
“The starkly decreased consumption of diesel contributes to climate conservation and keeps water pollution as low as possible,” Kverneland says — a key concern of the government in Norway.
And one of the managing directors of Kvarøy and Kverneland customer Gjermund Olsen is equally pleased, stating: “We purchased, installed and forgot about the rechargeable battery. It runs on its own and is totally maintenance-free.”
His employees, who visit the barge to conduct maintenance work once a week on average, don’t even have to perform additional work thanks to the new energy system. On the contrary: they benefit from improved working conditions. Since the diesel generators are only rarely in operation, noise levels and vibration effects are lowered and the fish farm produces fewer emissions.