LNG Providing Cold Comfort
By Jack Burke18 May 2016
By Bo Svensson
The Finnish ship Polaris—the world’s first icebreaker fueled by liquefied natural gas (LNG)—recently left the Arctech Helsinki Shipyard for the start of her sea trials.
The icebreaker, built for the Finnish Transport Agency, has been designed to cope with the demanding operations in the Baltic Sea, the shipyard said. It is designed to move continuously through around 1.6 m ice, and to break a 25-m channel through 1.2 m ice at 6 knots. Polaris is also designed to handle oil spill response operations as well as emergency towing missions and rescue operations.
The 110 m Polaris is equipped with five Wärtsilä dual-fuel engines and can operate on low-sulfur diesel and LNG. One engine is an eight-cylinder in-line 1280 kW Wärtsilä 20DF engine, two are nine-cylinder in-line 34DF engines, each of 4500 kW, and two are 12-cylinder Wärtsilä 34DF V-engines each providing 6000 kW of power.
The larger bore 34DF engines are in one large mid-ship engine room, while the smaller 20DF engine is located in a separate space. All the diesel/gas electric engines are connected to the ships electric grid feeding the propulsion motors as well as general ship consumption.
All Finnish ice breakers are equipped with electric motors for propulsion. In the case of Polaris, the vessel is equipped with three ABB Azipod units, two located in the aft and one in the bow.
According to the shipyard, Arctech in Helsinki, Finland, Polaris will be the world’s most environmentally friendly icebreaker. They said its design life of 50 years is unique for an LNG/diesel dual fuel vessel. The ability to operate on LNG fuel will reduce emissions as well as operation costs, the shipyard said.
When the contract was announced in 2014 the contract value was estimated by Arctech Helsinki Shipyard to around €123 million.