The trawler has been lengthened as part of a very extensive refit, which has included a conversion to diesel-electric propulsion and the installation of the largest capacity battery pack yet to be fitted to any fishing vessel.
It has emerged as Nordbas from its refit at the Green Yard Kleven in Ulsteinvik as trawler/seine netter with a suite of new technology, including hybrid propulsion, electric winches and the use of waste heat to heat the vessel.
Older fishing vessels have been largely out of the picture in terms of environmentally friendly propulsion systems as the attention has been on new capacity with floating frequency systems and diesel-electric propulsion, as well as LNG and battery installations. But there are also real possibilities for operating older tonnage more efficiently.
Nordbas was built as fresher trawler Sigurbjörg at the Slippstöðinn yard in Iceland in 1979, and later converted to a freezer. Operated by Siglufjörður company Rammi, it was replaced in 2017 when the new Sólberg ÓF-1 was delivered and the same year it was sold to its new Norwegian owners.
Originally with a 56 metre overall length and a 10.30 metre beam, Nordbas was taken to the Green Yard Kleven for a new factory deck capable of handling 80 tonnes of whitefish or 15 tonnes of shrimp per day to be fitted, along with a new wheelhouse and for the propulsion system to be overhauled.
With some major changes to the stern section to accommodate the innovative propulsion system, Nordbas’s length has been increased to 60.50 metres. This meant making space for the shaft generator, battery compartment, switchboard and control room for the winches.
Seaonics has supplied four new 40-tonne pull Big Drum PM winches with capacity for both trawling and seine netting. With twin-rig gear shot away, the deck equipment system recovers around 600kWh of energy, which flows to a 1600kWh battery pack.
This can also be charge dusing a shore power connection, and provides the possibility of peak shaving to even out energy usage on board, which contributes to fuel savings.
The largest battery pack so far installed on a fishing vessel, this alone represents a €1 million investment, while the overall cost of the refit runs into ’tens of millions of Euros,’ according to Nordbas’s owners.
‘We do not know the exact price of a new building with the same specification. It is not certain that it would be considerably more expensive to build a completely new vessel. But we are a company that focuses on re-use and on the environment. For us, it suited our philosophy to make use of an existing trawler,’ said Nordnes operations manager Mats Grimstad.
‘We believe that the future will see more re-use in all sectors. The buy-and-throw society will suffer when there is a shortage of resources. There may be many years before we are at that point, but we can at least do our part to slow down development. It costs to push forward with new technology. But now that the vessel has come into operation, we see that it was right to take the extreme measures to save energy in the long term,’ he said.
‘We see it as realistic to save 1000m3 of diesel a year with the engine and propulsion solution we have chosen. The entire project is optimised with a focus on fuel consumption.’