New ultra-low emissions Wärtsilä 31DF cuts methane slip

Wärtsilä’s new ultra-low emissions version of the Wärtsilä 31DF engine [ Image: © Wärtsilä]

Wärtsilä has introduced a new ultra-low emissions version of its Wärtsilä 31DF engine, first introduced in 2015. When operating on LNG, this new version of the dual fuel engine can further reduce methane emissions on a 50% load point by up to 56% and nitrogen oxide (NOx) emissions by up to 86%. On a weighted average, the engine’s new technology can reduce methane emissions by 41% more than the standard Wärtsilä 31DF engine, which is claimed to already have the lowest emission levels on the market.

Although methane slip from LNG-fueled engines is relatively small amount from a percentage standpoint, methane is a significantly more potent greenhouse gas than CO2 – up to 28 times greater. Cutting methane emissions is widely seen as important to the future of LNG as a clean fuel.

The new version, which has been applied on one of the four engines on board Wasaline’s Aurora Botnia ferry, has already helped the Finnish-Swedish ferry operator further reduce the ferry’s methane emissions by 10%. As part of the EU co-funded Green Ray and SeaTech projects, Wärtsilä piloted the ultra-low emissions concept onboard the Aurora Botnia with exceptional results verified through an independent study conducted in December 2022 by VTT, the Technical Research Center of Finland.

Encouraged by the positive results of the pilot, Wärtsilä has now launched the new ultra-low emissions version of the Wärtsilä 31DF engine on the commercial market.

This latest pilot is part of a long-term partnership between Wärtsilä and Wasaline to reduce emissions onboard the Aurora Botnia

“We are very committed to decarbonisation, and we have worked closely with Wärtsilä to make sustainable shipping a reality. It is a goal-oriented partnership that benefits both companies, as well as the industry as a whole,” said Wasaline managing director Peter Ståhlberg. “We have been pleased to allow the Aurora Botnia to be utilized as a floating laboratory, and we are excited to see the success of this latest Wärtsilä technology breakthrough.”

The standard version of the Wärtsilä 31DF engine platform already meets today’s regulatory requirements. The new version will enable operators to go even further in reducing methane emissions, helping to futureproof their vessels in the longer term against potentially tightening global requirements. What’s more, says Wärtsilä, improving dual fuel technology to enable methane emissions reduction will have a major impact on the long-term viability of LNG as a marine fuel.

“Our work around reducing methane slip and GHG emissions is part of Wärtsilä’s effort to continuously improve efficiency and reduce emissions of our products, and this new innovation is one more very important step along the road to decarbonization,” commented Stefan Nysjö, vice president of power supply, Wärtsilä Marine Power. “The building of an LNG fuel infrastructure has been an important factor in shipping’s transition towards cleaner operations, and Wärtsilä continues to create solutions that support this journey. Our focus has always been to improve and optimise existing solutions, and to develop exciting new ones. With this latest introduction, we are clearly delivering on this commitment.”