Wärtsilä introduced the NextDF feature for the Wärtsilä 25DF dual-fuel engine, which means while operating on liquefied natural gas (LNG), the NextDF feature reduces methane emissions to less than two percent of fuel use across all load points, achieving as low as 1.1 percent in a wide load range.
https://www.marinelink.com/news/wrtsil-nextdf-tech-help-cut-vessel-518683