The Daewoo Shipbuilding and Marine Engineering (DSME) yard in South Korea has ordered a total of 54 Wärtsilä dual-fuel engines to power 172,600 cbm icebreaking LNG carriers being built for use in arctic conditions to serve the Yamal LNG project in Northern Russia. The ships will be owned by one joint venture between Teekay LNG Partners of Canada and China LNG Shipping (CLNG), and another joint venture between China Shipping LNG Investment Co.,Ltd. (CSLNG) and Japan based Mitsui O.S.K. The order for engines was placed with Wärtsilä’s Korean joint venture company, Wärtsilä Hyundai Engine Co., (WHEC) in October.
The Wärtsilä machinery is capable of operating on liquefied natural gas (LNG), heavy fuel oil (HFO), or low-viscosity marine diesel oil (MDO) but LNG will be the main type of fuel to be used. When operating in arctic waters the engines will be operating in ambient temperatures of as much as minus 50 degrees Celsius on LNG carriers breaking through ice more than two metres thick, in operating modes that allow dramatic variations in engine load within a limited period of time.
For each LNG carrier Wärtsilä will supply 12-cylinder and 9-cylinder Wärtsilä 50DF dual-fuel engines. The total power output from the Wärtsilä engines is 64,350 kW per vessel.
“This very important order once again emphasises the technical leadership that Wärtsilä has established in dual-fuel engine technology. The fitting of Wärtsilä 50DF engines onboard the first LNG carriers in 2006 set a trend in the industry and since that introduction, 65 percent of all new LNG carriers have been fitted with Wärtsilä dual-fuel engines. The strong success of this particular engine over the alternatives is based on its superior propulsion efficiency and the clear environmental advantages that operating on gas allows,” says Mr Lars Anderson, Vice President, Wärtsilä Ship Power.
Wärtsilä has to date supplied more than 160 ships with its Wärtsilä 50DF machinery.
Wärtsilä 50DF engine
The Wärtsilä 50DF engine is manufactured in various configurations from a 6-cylinder in-line version to an 18-cylinder version in V-configuration, giving 950/975 kW per cylinder and a total maximum mechanical output of 17,100 kW. The engine speed is 500 or 514 rpm with 50Hz and 60 Hz applications. The maximum thermal efficiency is higher than with any other gas engine.
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. Additionally, the sulphur oxide (SOx) and particle emissions are negligible at almost zero percent.