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January 2013 www.sname.org/sname/mt VESSEL REPORT VESSEL REPORT: BIT VIKING When Tarbits 25,000 dwt Bit Viking prod- uct tanker was launched in 2007 to enter service for Statoil, the Norway-based international energy company, few people expected the ship to be back within four years for major engine modications. But that is just what happened. To understand the reason, lets look at some historical background. Kyoto and Norways commitments Norway was one of the original signatories of the Kyoto agreement to reduce greenhouse gases, with the Norwegian government ratifying the agreement in 2002. For a long time, Norway has had a strong focus on reducing human impact on the environment. In 2007, the Northern European country began imposing a tax on nitrogen oxides (NO X) emissions for ships with engine power greater than 750 kW trading between its ports. Switching to liqueed natural gas (LNG) fuel is an eec- tive way to reduce or avoid the NO X tax. Established in 1972 by an act of the Norwegian parliament, Den norske stats oljeselskap? (or Statoil as it is now known) signaled Norways desire and intention to shape its own future in oil and gas, of which abundant supplies had recently been discov- ered o its shores in the North Sea. Part of Statoils heritage has been to seek or invent technological solu- tions improving on the status quo. e Swedish shipping company, Tarbit, has been in operation since the early 1960s, safely transport- ing cargo such as bitumen, petroleum products, and chemicals. Tarbit originally took delivery of Bit Viking from Shanghai Edward Shipbuilding in China in 2007; the ship was the latest delivery in an active newbuild- ing program that had been ongoing since 1999. Upon delivery, Bit Viking went straight into service for Statoil on a time charter to distribute products from the com- panys renery at Mongstad, just north of Bergen on the west coast of Norway, to destinations all along the coast of the country. While Bit Viking was originally built as a conven- tional product tanker, with four-stroke diesel engines using heavy fuel oil (HFO) for bunkers, Statoil soon saw the potential to convert the advanced Wärtsilä 6L46 engines to 6L50DF engines, also supplied by Wärtsilä. is would enable the use of LNG as fuel for the tanker. LNG as fuel in the marine industry has been around for some time, with LNG carriers built in 1964 and onwards having used the LNG boil-off as fuel for their steam turbine propulsion. e LNG car- rier Venator was delivered in 1973 by Moss Rosenberg Shipyard in Norway with a low-speed dual-fuel Sulzer Tarbits 25,000 dwt Bit Viking product tanker was converted from using four- stroke diesel engines to LNG power.