A consortium in Italy has designed an LNG-driven tug to cut emissions from manoeuvring ships into harbours and terminals
Marine Engineering Services (MES) teamed up with Engys and Università degli Studi di Trieste to design Tuga, an escort tug powered by gas. They have been working on the design since the project was officially launched in October 2018. As an added complication, Tuga was designed to operate in shallow waters.
The partners received funding of €614,000 (US$729,480), out of a budget of €937,000 (US$1,133,000) from the European Regional Development Fund, as part of the Regional Operational Program (2014-2020).
This project involved drafting a new propulsion system based on an LNG fuel system.
“In this regard, the layout of the fuel system container will be optimised both in terms of shape and size while meeting all the safety requirements on board,” said Engys.
Its design was optimised using high-fidelity computational fluid dynamic (CFD) and validated using a set of towing tank experiments.
When Tuga is built, it will be equipped with a real-time control system software to assess the dynamic equilibrium of the hull body during escort trial operations, based on the inputs provided by hydrodynamic and propulsions forces calculated during CFD studies.
This Tuga design has an overall length of 36 m, breadth of 14 m, can store 80 m3 of LNG, accommodate up to eight workers and would have a fixed-point firing capacity of 60 tonnes.
MES was responsible for arrangement of the fuel containment system and optimisation of hull and topside geometries, while taking into account the safety requirements.