GTT has obtained an Approval in Principle (AiP) from DNV for its Mark III membrane LNG tank design rated for 1 barg, surpassing the current standard of 0.7 barg, according to GTT's release.
This approval extends the operational range of the Mark III technology, following DNV’s previous AiP for a 2 barg design pressure on smaller-capacity tanks, notably suited to cruise ships.
Key benefits for ship-owners include:
-Extended Pressure-Holding Time: The increased design pressure lengthens the duration before the tank reaches maximum pressure, reducing the need to burn boil-off gas during low engine load periods.
-Warmer-Temperature Bunkering: Vessels can load LNG at higher temperatures, allowing access to a broader range of LNG suppliers.
-Cold-Ironing Compliance: The enhanced pressure capacity enables LNG-powered vessels to meet upcoming cold ironing regulations at quayside, such as those under the AFIR directive, without compromising tank integrity.
DNV’s AiP confirms that GTT’s 1 barg solution achieves safety equivalence with conventional atmospheric-pressure tank designs.
The approval is based on a comprehensive evaluation of containment integrity, fuel gas handling systems, tank domes, and hull structure under elevated pressure scenarios.
Philippe Berterottière, Chairman and CEO of GTT, stated: “We are pleased to secure DNV’s Approval in Principle. This innovation underlines our commitment to delivering practical, future-proof solutions that enhance operational flexibility, reduce emissions and support ship-owners in meeting evolving environmental regulations.”
Martin Cartwright, Global Business Director, Gas Carriers at DNV, commented: “We are thrilled to be working with GTT on this project and to award this AiP for this membrane tank development. This represents a significant step in enhancing LNG tank flexibility to meet evolving regulatory demands and is a good example of how technical advancement and regulatory foresight can go hand in hand to support the maritime energy transition. We look forward to continued collaboration.”
GTT (Gaztransport & Technigaz) is a French engineering company specializing in the design of membrane containment systems for the transport and storage of liquefied gases, particularly LNG.
DNV (Det Norske Veritas) is an international accredited registrar and classification society headquartered in Norway. DNV provides certification, technical assurance, and advisory services to the maritime, oil and gas, and energy industries.