December 13, 2019. Robert Allan Ltd. and Rolls-Royce have developed what is believed to be the world’s first shallow-water push boat powered by liquefied natural gas (LNG) engines.
At the International Workboat Show in New Orleans, classification society DNV GL gave its ‘approval in principle’ (AiP) to the new design. Powered by two MTU 8V 4000 M55RN natural gas engines from Rolls-Royce and designed for use on inland waterways, the push boat is more cost-effective to operate, and produces less pollutants and climate-unfriendly exhaust gases than vessels with conventional propulsion systems.
Robert Allan Ltd. and Rolls-Royce collaborated to design the gas-powered shallow-water push boat based on the proven Robert Allan Ltd. RApide 2800-Z2 design which is already used on some diesel-powered vessels on the Amazon river. The vessel design was specially modified for LNG to accommodate the two 746 kW engines (complete with IMO Tier III emission control systems) and the entire LNG supply system – also provided by Rolls-Royce – as well as the gas control and safety systems and the overall vessel control system.
The hull – externally unchanged from the RApide design – was internally redesigned to accommodate the 70 m3 gas tank as well as the usual engine accoutrements, and to provide the crew with a pleasant working environment. The lower deck crew cabins, salon and galley were moved up one level and the deckhouse was enlarged.
The AiP from DNV GL certifies that the design complies in principle with the classification society’s rules for classification of maritime vessels and the international safety regulations for vessels using gas or other low-flashpoint fuels. It is an independent evaluation of the design concept within a given framework and states that the design is fundamentally feasible and there are no fundamental implementation concerns.