The PERFECt JIP looked at the potential of developing an electric-driven 20,000 TEU ultra large container vessel (ULCV) with an LNG-fuelled combined cycle gas and steam turbine (COGES) electric 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 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”, noted Gerd Würsig, Business Director for LNG-fuelled ships at DNV GL – Maritime.
As the project partners explain, the use of combined gas and electric steam turbine (COGES) systems, in combination with an all-electric design, offered several advantages. Propelling the ship with electrical motors enabled the power generation and propulsion systems to be placed in separate sections of the ship. In addition, the COGES system provided power for both propulsion and auxiliary systems, so an engine room was not needed any more and the power plant, together with the integrated LNG tanks, could be moved below the deck house - freeing up considerable space for more container slots.
“The COGAS electric propulsion system provides larger flexibility for arrangement of containers in combination with a high overall propulsive efficiency of the vessel,” said Thomas Eefsen, Chief Commercial Officer, OMT.
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 tailormade 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.
“The PERFECt project impressively demonstrates how the innovative coupling of established technologies can generate new options for marine propulsion,” said Prof. Dr.-Ing. Christoph Pels Leusden, Beuth University of Applied Sciences Berlin.