Ostensjo tug

Wärtsilä will provide its dual-fuel (DF) engines integrated with a customised gas storage and supply system for three new large escort tugs contracted by Norwegian operator Østensjø Rederi.

Wärtsilä engines will give these LNG tugs the flexibility to select the most suitable fuel according to availability, price and local environmental restrictions.

The tugs will be equipped with six-cylinder Wärtsilä 34DF dual-fuel engines and the LNG system will be incorporated with the LNGPac fuel system, a fully integrated gas-handling system, and the gas valve unit (GVU).

The equipment is expected to be delivered during the first half of 2016.

"The dual-fuel engine technology also ensures a high level of operational security since the switch from gas to diesel can be made at any time without loss of speed or power."

Østensjø Rederi project manager Carl Johan Amundsen said: "These are trend-setting tugs in that they provide environmental sustainability through the use of LNG fuel.

"Wärtsilä is the technology leader in making this trend possible.

"At the same time, the flexibility of the dual-fuel engine technology also ensures a high level of operational security since the switch from gas to diesel can be made at any time without loss of speed or power."

Designed by Robert Allan, the vessels will have a bollard pull of 100t and will be operating at Statoil’s Melkøya terminal near Hammerfest, Norway.

Recently, Wärtsilä secured an order from China’s Hudong-Zhonghua Shipbuilding for the delivery of LNG reliquefaction plants and gas-handling systems to four LNG carriers being built at its yard.

Image: The new escort tugs contracted by Østensjø Rederi will feature Wärtsilä dual-fuel engines. Photo: courtesy of Robert Allan Ltd.