Engine details revealed for methanol-ready diesel-electric hybrid offshore tug

Ostensjo Rederi's methanol-ready diesel-electric hybrid tug newbuilding will have a Caterpillar Marine propulsion package, according to the enginebuilder's exclusive distributor in Norway. Zeppelin Power Norway reported it will supply two Cat 3516E main engines, two Cat 3512E variable speed gensets, one Cat 9.3 harbour generator and one Cat C4.4E emergency generator for the 50-m offshore tug under construction at Gondan Shipyard in Spain. "The newbuild represents a major step in further strengthening our offshore towage fleet," said Ostensjo Rederi chief executive, Kristian Helland Vea.

When delivered, the newbuild will be the largest and most powerful offshore tug in the Norwegian owner's fleet. "The tug ticks all the boxes. The combination of high bollard pull, advanced hybrid propulsion and large winch capacity ensures high operational flexibility," said Mr Vea. As previously reported[1], the as-yet unnamed DP2-class vessel will be based on Skipsteknisk ST-933 design and delivered in Q1 2028.

It will have a beam of 17 m, accommodation for 14, a bollard pull of 150 tonnes, and Kongsberg Maritime's permanent-magnet RIM-drive manoeuvring propellers. Noting the tug will set "a new benchmark for bollard pull relative to its size," Zeppelin Power said the vessel's two 16-cylinder Cat 3516E generator sets will run at variable speed to optimise fuel consumption, reduce noise, and minimise emissions. "When maximum pulling power is required, the two 3516E engines connect directly to the shafts, delivering immense power within a very compact footprint," said the distributor. Six sequential turbochargers will significantly boost the Cat 3516E engines' power and efficiency across the entire speed range.

The generator sets are double insulated for maximum noise and vibration reduction to increase crew comfort.

For emissions compliance, the four-stroke, high-speed engines are fitted with selective catalytic reduction aftertreatment systems for exhaust cleaning and are prepared for biofuel and future conversion to methanol.

Riviera's Annual Offshore Support Journal Conference, Awards & Exhibition 2026 will be held in London on 3-4 February 2026. Use this link[2][3] for more information and to register for the event.

References

1. ^ As previously reported (www.rivieramm.com)
2. ^ Annual Offshore Support Journal Conference, Awards & Exhibition 2026 (events.rivieramm.com)
3. ^ Use this link (events.rivieramm.com)