Danish offshore crew transfer specialist MHO has earlier this week taken delivery of two hybrid crew transfer vessels, after what was described as an ultimate sea trial.
Namely, the vessels arrived in Esbjerg, Denmark after a 12,000 nautical mile journey from China, for which developers of propulsion technology Volvo Penta and Danfoss Editron said was a voyage of discovery, with the many lessons learned helping to create a tailor-made solution fit for the owner’s requirements.
Measuring 34.4 meters in length and with an 11-meter beam, these vessels will be run by operator MHO-Co and service the Hornsea Project 2 offshore wind farm in the North Sea.
The vessels’ power system, developed by Volvo Penta and Danfoss Editron, is an integrated solution made up of a Danfoss Editron electric drivetrain supported by Volvo Penta variable speed gensets that drive two of the first Electric Volvo Penta Inboard Performance System (IPS) units as well as two D13 Volvo Penta IPS units.
Danfoss Editron and Volvo Penta said they'd treated the journey from China to Denmark as a pilot project and a time to work with the captains and crew to tweak the novel technology onboard and make it as reliable and efficient as possible for the customer. The companies were able to test different power combinations, such as diesel-electric operation or diesel-only. In Dynamic Positioning System mode, fuel consumption is below 20 liters/hr. and can be as low as 17 liters/hr. which, they say, is exceptional for vessels of this size class.
From the initial learnings, the teams have started adapting the drivetrain – not just the motors themselves – to all-electric propulsion needs.
"The new IPS units have already achieved 1,000 hours of operation before even reaching the customer. This impressive milage has given all the teams time to test and adjust the system to create a tailor-made solution that fits the owner’s requirements," the companies said in a statement.
“These systems are a very important first step towards the future of sustainable operations at sea,” says Mik Henriksen, CEO of MHO-Co. “We believe it is our shared responsibility to drive more sustainable solutions in the marine sector, and the best way to do this is through collaboration.”
Now, before the vessels enter operation, batteries are being installed in Denmark to provide stored power for zero-emissions operation. This system will allow the vessels to operate in zero-emission electric mode for up to eight hours or, in combination with diesel propulsion, to achieve a maximum speed of approximately 24 knots. Using multiple modular generators allows operators to tailor power generation to the operational profile and enhance flexibly.
“We’re excited to see these vessels go into action in the North Sea. This pilot project has been hugely beneficial in helping us create the building blocks for future projects,” adds Jacob Vierø, Sales Project Manager, Volvo Penta. “Each operation will be different and require a tailor-made propulsion solution, but this project has allowed us to both develop the technology and collaborative process that can be adapted for future commercial operations.”