On board Norway's greenest tugboat

- "On longer transport assignments, we can run in so-called e-mode and cut diesel consumption by up to 75 per cent," says the chief engineer on board what is Norway's least polluting tugboat.

The vessel is built in 2014 and was incorporated into the FFS fleet at the beginning of 2020. It is mainly used for port towing, long towing, assistance and salvage.

The boat has two propellers - one at each end. These are driven from two separate engine rooms, each of which has a diesel engine with 1800 horsepower and a generator that produces enough electric motor power for the boat to maintain a cruising speed of eight knots.

The generator is powered by a marinated truck engine with over 500 horsepower.

- WE TURN ON the main engine when we're towing. Otherwise, we mostly run in e-mode. This means we can only use the power when we need it. It's good for the environment," says the skipper on board.

He experiences that customers are increasingly concerned with sustainability. Especially in larger ports near the cities, there is a strong focus on emissions.

The fuel savings from driving electrically are also significant. Both on long haul, which FFS Athos is often used for, and on transport stages to and from port jobs.

- "We spend 80 per cent of our time travelling between assignments. That's when we save diesel," says the skipper.

WHEN THE BOAT PICKED UP a seismic hull in Gibraltar, it went on e-mode all the way down. On the tow ride back, the main engine was engaged.

- "We used 25 cubic metres of diesel down to Gibraltar and 140 cubic metres back home. A normal tugboat might have used 100 cubic metres down and the same amount back," says the chief engineer.

IN ADDITION TO a skipper and a chief engineer, there are two sailors and one helmsman on board. The crew is divided into two shifts, which are patterned for four weeks at a time.

FFS Athos is also equipped with a port generator, which is put into operation when the boat is at a port that does not have shore power. A seawater-based heat pump also provides heating and cooling in the cabins on board. The wheelhouse has its own heat pump.

FFS ATHOS has one propeller in the bow and one stern, also which is very useful. During a tow, it can be moored anywhere on the ship it assists. And it can quickly move the trailer to all sides.

- "We can spin round, do little pirouettes and go sideways at nine knots. Not many other tugboats can match that," smiles the engine manager.

The boat is built a little differently than most other tugboats. Therefore, it can be demanding to see what is in front and what is behind.

- But the advantages outweigh the disadvantages. "It's perhaps the chief engineer who is most affected by the way the boat is built. "He has to run between two engine rooms," jokes the skipper.