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26 Maritime Reporter & Engineering News LNG/LPG As the final bastion of steam turbine propulsion in mercantile shipping, the boom in the LNG carrier sector has not only given a fillip to the Japanese pro- ducers of such specialist plant, but has also sparked the uptake of alternative powering solutions. The recent entry into service of the first LNG tanker installed with a dual-fuel electric propulsion system, and the nomination of the concept for a clutch of subse- quently-contracted, larger gas carriers, are likely to have forever altered the established order in deepsea LNG carri- er powering. Steam turbine systems have monopolized large, single-screw LNG carrier propulsion over the past four decades due to factors of reliability, familiarity and the ease with which the boilers in such installations can use the gas boil-off which continuously emanates from the LNG cargo. Mitsubishi and Kawasaki have both augmented their offering with steam tur- bines suited to a new generation of high- er capacity LNGCs. However, techno- logical advances in main engines and innovation in propulsion systems, cou- pled with growing ship size and evolv- ing trade requirements, draught limita- tion implications for hull and propeller design, and heightened expectations as to unit cost efficiency and operating flexibility, have prompted shipowners to consider new options. The 74,000-cu. m. Gaz de France Energy, which was recently completed by Chantiers de l'Atlantique and phased into service carrying Algerian gas to France, has opened a new technical chapter in LNG marine transportation. It is the first LNGC to incorporate dual- fuel reciprocating engine, electric-drive system, and has also given form to GTT's CS1 membrane cargo contain- ment technique, offering improved qual- ities and operating advantages and reduced costs compared with earlier sys- tems. Both the propulsion concept and CSI cargo system have also been speci- fied for two vessels of 153,500-cu. m. ordered from Chantiers de l'Atlantique. Gaz de France energy is equipped with four six-cylinder Wärtsilä 50DF dual- fuel engines, giving a total power output of 22.8-MW, and driving gensets deliv- ering electrical energy to a pair of Alstom propulsion motors and all other shipboard consumers. The follow-on, larger newbuilds, Provalys and Gaselys, will each have three 12-cylinder 50DF dual-fuel engines plus one six-cylinder model, giving a power concentration of 39.9-MW. Kawasaki Shipbuilding Corporation delivered Energy Advance, a large LNG carrier with LNG carrying capacity of 145,000 cu. m., to Tokyo LNG Tanker Co., Ltd. Kawasaki developed the LNG carrier of this class, which can visit any LNG ter- minal ports worldwide, with similar dimensions to the conventional 130,000 cu. m. class. The carrier is the fourth newbuilding of the 145,000 cu. m. class and second delivery to Tokyo LNG Tanker. The four LNG cargo tanks are of the independent spherical MOSS type. The heat insulation is the Kawasaki panel system that demonstrates a high heat insulation effect. This insulation system maintains the boil off gas rate at approximately 0.1% a day. The cargo tanks are installed inside the compart- ment built with double side shells and double bottom to ensure safety so that the cargo tanks are not damaged direct- ly. The wheelhouse is equipped with advanced integrated navigation equip- ment, which has improved ship opera- Circle 219 on Reader Service Card Circle 203 on Reader Service Card Circle 239 on Reader Service Card 7 U X H I R U H Q V L F D Q D O \ V L V R I Z K D W U H D O O \ F D X V H G W K H G H P L V H R I W K H 7 L W D Q L F W K H % U L W D Q Q L F D Q G W K H / X V L W D Q L D / L V W 3 U L F H 2JE EE , 6 % 1 E%NHNLLH%HJ% ; 3 X E O L V K H G E \ 7 K H 6 R F L H W \ R I 1 D Y D O $ U F K L W H F W V D Q G 0 D U L Q H ( Q J L Q H H U V 7 , 7 $ 1 , &