Finnish engine manufacturer Wärtsilä has released its 20DF dual-fuel marine engine for sale in the US market. The engine, which can operate with liquefied natural gas (LNG) or diesel oil, meets the strict emissions compliance criteria of the United States Environmental Protection Agency (EPA) Tier 4 and is now available to American ship owners and operators.
Wärtsilä says the release is in response to the growing demand for natural gas fueled engines. Lars Anderson, Vice President, 4-stroke at Wärtsilä Ship Power, states: “The Wärtsilä 20DF will further accelerate the adoption of LNG as a marine fuel in the US. The ability to meet U.S. Environmental protection Agency (EPA) Tier 4 emissions requirements without the need for exhaust after-treatment, while at the same time increasing the safety and operational flexibility for LNG vessels, provides significant value to our customers.”
The North American Emissions Control Area (ECA) came into force in August 2012. The legislation is aimed at achieving stricter control on emissions of sulphur oxides (SOx), nitrogen oxides (NOx) and particulate matter from vessels. ECA’s have also been established in the Baltic Sea and North Sea.
The Wärtsilä 20DF is a commercial duty, medium-speed, dual-fuel engine. Engines supplied to the US market will operate primarily on natural gas, with marine diesel oil (MDO) as a pilot fuel or as an emergency backup fuel.
The Wärtsilä 20DF power spans the range from 1,056kW (1,415HP) to 1,584kW (2,122HP) per engine.
Wärtsilä’s lean burn, low pressure dual-fuel engine technology utilizes a very low percentage diesel fuel as a pilot ignition source, amounting to about 1 per cent of total energy. This contrasts with other gas engine technologies that employ a significantly higher percentage of diesel pilot fuel. The Wärtsilä lean burn advantage results in lower operational costs and reduced emissions.