Technology group Wärtsilä will supply the engines for a new purpose-built semi-submersible Heavy Transport Vessel  which is designed to minimise exhaust emissions and maximise fuel efficiency. The ship is being built for Switzerland-based offshore contractor Allseas Group at the Guangzhou Shipyard International (GSI) facilities in China. The engine order was booked by Wärtsilä in Q4 2025.

The future-proof Wärtsilä 31 engine was selected because of its modular design, which enables a significant reduction in maintenance requirements and costs, and its readiness to use alternative sustainable fuels.

“This new HTV strengthens the flexibility of our fleet and how we deliver projects. We selected the Wärtsilä 31 engine for its high efficiency, future-ready design and ability to transition to low- and zero-carbon fuels, which supports both operational adaptability and our long-term sustainability ambitions,” says Sytske de Groot, Manager, Naval Architecture – Allseas.

The vessel will operate with four Wärtsilä 31 engines, each fitted with a Wärtsilä NOx Reducer for emissions abatement. Delivery is scheduled for the first quarter of 2028.

“The Wärtsilä 31 engine delivers what the industry needs today and prepares operators for tomorrow. Its exceptional fuel efficiency reduces operating costs immediately, while its capability to convert to sustainable fuels ensures a clear path toward decarbonisation. This makes it one of the most future-ready propulsion solutions available,” comments Stefan Nysjö, Vice President, Power Supply, Wärtsilä Marine.

Wärtsilä has already supplied equipment to a number of vessels for Allseas, including the engines for Allseas’ purpose-built cargo barge, ‘Braveheart’.