The Nor-Shipping event in Oslo this week has highlighted Liquefied Natural Gas (LNG)’s continued emergence as a viable, cleaner marine fuel. In this instance, project partners ABB (Switzerland), OMT (Denmark), GTT (France), Caterpillar’s Solar Turbines (USA), CMA CGM (France), its subsidiary CMA Ships, and DNV GL (Norway), presented the results of phase II of the PERFECt joint industry project (JIP). Phase II looked to validate the phase I results and develop the concept to a “ready to order” stage.
The PERFECt JIP looked at the potential of developing an electric-driven 20,000 TEU ultra large container vessels (ULCV) with an LNG-fuelled combined cycle gas and electric steam turbine (COGES) power plant. The goals for the project were to to utilize LNG as a primary fuel for an ultra-low emissions profile, in a design with at least the same carrying capacity and efficiency as existing ULCCs.
“The PERFECt project has brought a new set of expert capabilities together and delivered promising results,” said Gerd Würsig, Business Director for LNG-fuelled ships at DNV GL – Maritime. “The impulse behind this project was the interest in seeing how a modern ultra large container ship design could benefit from clean fuel and highly efficient COGES technology. We have achieved our objectives and now have a validated design concept with enough technical detail to develop a business case.”
The use of a COGES system, in combination with an all-electric design, offered exceptional performance with several advantages. Propelling the ship with electrical motors enabled the power generation and propulsion systems to be placed in separate sections of the ship. And with the COGES system providing power for both propulsion and auxiliary systems, an engine room was not needed any more. So, the power plant, together with the integrated LNG tanks, could be moved below the deck house – freeing up considerable space for more container slots.
“Our SoLoNOx Dry Low Emissions (DLE) Gas Turbines, which operate on LNG, will not only exceed any current marine emission restrictions, but provide a wide margin against anticipated future restrictions. The resulting optimized power generation system is both reliable and highly efficient while being increasingly environmentally friendly,” said Barbara Stanley, Vice President, Power Generation and Strategic Development, Solar Turbines Inc. (a Caterpillar Company).
In addition to the improved overall arrangement of the vessel, a tailored hull shape and new propeller design add to the overall efficiency. The novel hull form with vertical bow is tailor-made to the operational profile of the vessel, and with a high efficiency propeller in combination with a contra-rotating pod, the total propulsive efficiency is increased by around 5 per cent.
(Source: DNV GL)