Improving marine winter navigation

Monday, August 29, 2022

The Winter Navigation Motorway of the Sea II (WINMOS II) project, co-funded by the EU Connecting Europe Facility Programme, was a €7.6 million scheme aimed at developing and enhancing the maritime winter navigation system in the EU’s northernmost waters, such as the Baltic Sea.

Representing 15% of the world’s maritime transport, up to 2000 vessels cruise the Baltic Sea at any time. An average of 639 million tons of cargo are transported via the Baltic Sea annually.

One of WINMOS II’s key targets was the creation of a motorized icebreaking removable bow concept, which would enable ice-strengthened vessels to be used as icebreakers during the winter. At the time, icebreaking operations cost Sweden, Finland and Estonia €86 million every winter.

Effective crewless operations

The Finnish Transport Infrastructure Agency turned to Turku Repair Yard and Danfoss’ Editron division to develop and build Calypso, a new icebreaker concept boat equipped with an innovative hybrid motorized removable bow. The bow, the largest of its kind in the world, can break ice up to 70cm thick.

The icebreaker vessel operates in Lake Saimaa, where the ice is more solid than at sea. With winter temperatures that can plummet to -30°C, icebreakers are necessary for Finland, even during mild winters.

Danfoss’ Editron hybrid-electric system powers the removable bow with two generators, built as a DC system, and two permanent magnet electric motors for propulsion. The company also supplied a front supercapacitor to control peak powers efficiently.

The software inside the system also cuts fuel and delivers high efficiencies as the diesel generators in the DC system can be driven at variable speeds. Furthermore, the power plant and propulsion system of the removable bow are designed to be operated from the pusher tug wheelhouse. Meanwhile, the machinery can operate without crew members needing to be on board the vessel.

A more sustainable and efficient marine industry

Introducing hybrid-electric power to icebreaking operations will help Finland meet its target of lowering emissions by 40% by 2030 compared to 1990 levels.

The hybrid-electric removable bow is also making the marine industry more efficient and sustainable, as it enables virtually any kind of tug to become an icebreaker ship. In addition, Danfoss’ system can easily be optimized for future configurations and converted to a fully electric system if required.

This innovative approach also enables savings in capital costs, given that the bow is equipped with its own propulsion system and the pusher is only chartered for part of the year.


Project Hybrid-electric removable bow developed for a new icebreaker vessel concept

Turku Repair Yard

Location Lappeenranta, Finland
Scope The removable bow formed part of the Winter Navigation Motorways of the Sea II project, which aimed to develop and enhance the safety of the maritime winter navigation system.

A hybrid-electric removable bow that enables ice-strengthened vessels to be used as icebreakers during the winter.

Technical specifications

  • Two generators built as a DC system
  • Two permanent magnet electric propulsion machines
  • Front supercapacitor to efficiently control peak powers
  • High efficiency
  • Reduced fuel usage and emissions
  • Innovative system design with supercapacitors to ensure power plant stability in harsh ice conditions
  • Reduced capital costs
  • Can be operated without crew members being on board the vessel
  • Easily converted to a fully-electric system if required