Technology group Wärtsilä has introduced its NextDF technology for a third engine, the Wärtsilä 46TS-DF dual-fuel engine. While operating on liquefied natural gas (LNG), the Wärtsilä 46TS-DF engine with NextDF feature reduces methane emissions to less than 1.4 percent of fuel use across all load points, achieving as low as 1.1 percent in a wide load range. This is nearly three times lower than the default methane slip factor of 3.1 percent, specified in the FuelEU Maritime and IMO Lifecycle Guidelines for Otto-cycle four-stroke dual-fuel engines. Through improvements made to the combustion control, and through optimizing engine performance, the new feature also minimizes nitrogen oxide (NOx) and CO2 emissions.
LNG is an important transition fuel as the marine industry strives to reduce its carbon footprint. However, the main component of LNG is methane and when burned as a fuel, a small amount may not combust properly, leading to methane escaping into the atmosphere. Across the shipping industry, the use of LNG and cutting methane emissions is one of the most effective ways to decrease overall greenhouse gas (GHG) emissions from engines over the next decade, complementing other efforts to reduce CO2 emissions.
“NextDF technology reduces the environmental impact of vessels that use LNG as fuel, without compromising on performance or operational stability. Importantly, this makes it easier for ship owners to comply with increasingly stringent decarbonisation targets and legislation,” said Stefan Nysjö, Vice President of Power Supply, Wärtsilä Marine.
Launched in 2022, the Wärtsilä 46TS-DF engine has a two-stage turbocharging to deliver high levels of efficiency and power density across a wide operational range for vessels in all segments of the industry. This level of efficiency reduces fuel consumption and lowers emissions, while being retrofittable for sustainable fuels as they become widely available. By applying the NextDF feature, the engine will have the lowest methane emissions and GHG emissions in the /cylinder power range.
The Wärtsilä 46TS-DF with NextDF feature was developed as part of the EU co-funded GREEN RAY project. The initial installation of the Wärtsilä 46TS-DF engine with NextDF feature will be onboard the cruise ship, MSC World Asia, being built by Chantiers de l’Atlantique (CdA) in Saint-Nazaire, France for the Geneva-based cruise operator MSC Cruises.
