Wärtsilä’s NextDF Tech Slashes Methane Emissions in Marine Engines
Shipping’s transition to cleaner fuels just got a major upgrade. Wärtsilä has unveiled its NextDF technology for the Wärtsilä 46TS-DF dual-fuel engine, slashing methane emissions to as low as 1.1% of fuel use—far below industry benchmarks. The breakthrough could redefine LNG’s role in decarbonizing maritime transport.
The Methane Problem—Solved?
LNG has long been touted as a bridge fuel for shipping, offering lower CO₂ emissions than traditional marine fuels. But its Achilles’ heel? Methane slip—unburned gas escaping during combustion. Current FuelEU Maritime and IMO guidelines assume a 3.1% methane slip factor. NextDF crushes that figure, achieving emissions below 1.4% across a wide load range.
“This isn’t just incremental progress—it’s a leap toward making LNG a viable long-term solution,” says Stefan Nysjö, VP of Power Supply at Wärtsilä.
More Than Methane: A Triple Threat
NextDF doesn’t stop at methane. By refining combustion control and optimizing engine performance, the tech also cuts NOx and CO₂ emissions. The result? A dual-fuel engine that maintains operational stability while future-proofing vessels against tightening regulations.
The Wärtsilä 46TS-DF, launched in 2022, was already a standout with its two-stage turbocharging for high efficiency and power density. NextDF pushes it further, positioning it as the lowest-emission engine in its class for outputs above 1MW per cylinder.
From Lab to Luxury Cruise Ship
Developed under the EU’s GREEN RAY project, NextDF will make its commercial debut on the MSC World Asia, a Chantiers de l’Atlantique-built cruise ship for MSC Cruises. The choice of vessel is strategic—cruise operators face mounting pressure to reduce emissions while delivering uncompromised performance.
Retrofitting capabilities ensure the engine remains adaptable as sustainable fuels evolve. For an industry racing to meet 2030 decarbonization targets, Wärtsilä’s tech offers something rare: a solution that works today, with room to grow tomorrow.
