The air is expected to get significantly cleaner in Osaka Bay, Japan, following the entry into service of the LNG-fuelled, 250gt tug Ishin – representing another fine example of the country’s continuous green craft development drive. Ordered from Kanagawa Dockyard by Nihon Tug-Boat, a subsidiary of the Mitsui OSK Lines (MOL) Group, Ishin’s hybrid propulsive arrangement is expected to significantly curb CO2 emissions in her home territory of Osaka Bay – potentially by as much as 25%, compared to conventional, diesel-only tugs, MOL estimates. Utilising LNG means the tug should also release 84% less NOx content into the atmosphere, while SOx and PM emissions will be virtually stamped out.
Although this is not the first Japan-built tug to incorporate LNG as fuel (an achievement credited to NYK’s 37.2m, 2015-delivered Sakigake), the newbuild is reportedly the first of its kind to conform to the requirements of the International Code of Safety for Ships using Gases or other Low-flashpoint Fuels (IGF Code) (see Ship & Boat International May/June 2018, page 60). Since her launch in Q3 2018, Ishin has sufficiently impressed Japan’s Ministry of Land, Infrastructure, Transport and Tourism, which recently accorded the vessel a four-star rating – the highest recommendation possible – as part of its ongoing scheme to encourage the development of energy-efficient, low-emission, domestic coastal craft.
The launch of the tug coincides with the creation of Osaka Bay’s first portside LNG supply hub, situated in Sakai Senboku Port; the natural gas will be conveyed to Ishin by truck. MOL co-established this bunkering spot in a partnership with Osaka Gas Company, and Ishin took delivery of her first LNG load from this location in late January this year.
Ishin measures 43.6m x 9.2m and is designed to draw approximately 3.15m. The tug is powered by a pair of IMO Tier III-compliant Yanmar 6EY26DF dual-fuel engines, which can switch seamlessly between diesel fuel and LNG, and which grant the tug a speed of at least 16knots. The tug also utilises a detachable LNG tank, mounted on a platform at the vessel’s stern, so as to overcome the challenges posed by limited internal vessel space, and to simplify tank inspection and maintenance procedures.