Claiming record levels of efficiency combined with high power density and low raw NO
x emissions, Wärtsilä has launched the new Wärtsilä 31 medium speed engine (bore 31 x 43 cm). It targets a range of vessel types, including ships in the offshore and cruise and ferry sectors, is offered in 8, 10, 12, 14 and 16 cylinder vee configurations and covers a power range from 4.2 to 9.8 MW. Diesel, dual-fuel and spark-ignited gas versions are all available, giving operators the options of very light to very heavy fuel oils and a range of different gas qualities. Backing the record efficiency claim is a best diesel fuel consumption of 165 g/kWh. Contributing to the Wärtsilä 31 diesel version’s high power, high efficiency and low emissions are an advanced high pressure fuel injection system and two-stage turbocharging, enabling strong Miller Cycles.