Wärtsilä Supporting Japan's 'Gas Age' Shipping

A total of 16 new gas carrier ships being built in Japan for Japanese owners are to be powered by Wärtsilä dual-fuel engines capable of running on liquefied natural gas (LNG) or conventional diesel fuels. 

Wärtsilä's said its experience and technological capabilities in gas fuelled propulsion solutions were cited as being key factors in the award of these contracts – all placed between the second half of 2014 and December 2015.

The orders specify 20 nine-cylinder, 25 six-cylinder and 16 eight-cylinder Wärtsilä 50DF dual-fuel engines, for a total of 61 engines that will be running primarily on LNG and representing an expansion of Japan's gas fuelled merchant fleet. These will be the first Wärtsilä 50DF engines delivered for Japan's LNG carrier market. The first of the Wärtsilä machinery was delivered at the end of December 2015.

The 16 vessels have a gas cargo capacity of between 155,000 and 180,000 cubic meters. They will be employed mainly in delivering shale gas from the U.S. to Japan.

Wärtsilä said the propulsion efficiency of the Wärtsilä 50DF dual-fuel engine is one of the reasons for its success. The environmental advantages that operating on gas allows is another factor in the success of this technology. When operating in gas mode, the nitrogen oxide (NOx) emissions are at least 85 percent below those specified in the current IMO regulations, and CO2 emissions are some 25 percent less than those of a conventional marine engine running on diesel fuel, Wärtsilä noted.. Additionally, the sulphur oxide (SOx) and particle emissions are negligible at almost zero percent.

Both the gas admission and pilot fuel injection are electronically controlled. The engine functions are controlled by an advanced automation system that allows optimal running conditions to be set, independent of the ambient conditions or fuel type.