New ship handling tug & CNG powered tug

This demo case provides two demonstrators. The first demonstrator is the RSD (Reverse Stern Drive) 2513. This tug is of an entirely new type with improved hydrodynamic characteristics and TwinFin technology. These innovations increase the efficiency by allowing a smaller tug to do multiple heavy jobs in a safe way. To optimize the hydrodynamic behavior, comprehensive computational fluid dynamics (CFD) calculations and model scale tests have been carried out. The new design also allows the use of a smaller crew (three instead of four to five), which contributes to a decrease in operational costs. At the moment seven tugs have been built and all completed their sea trials successfully.

The second demonstrator is the ASD (Azimuth Stern Drive) 3212 CNG-E, which operates with compressed natural gas (CNG) as a fuel and has an additional hybrid (E) propulsion as well. At the moment there are four tugs operational with liquefied natural gas (LNG) as a fuel worldwide. These tugs use medium speed engines, which are voluminous, heavy and high on OPEX and CAPEX. This tug will use high speed engines, provided by MTU, to directly drive the thrusters. The use of these high speed natural gas engines offers a high-power density, combined with cost-efficiency, compared to the medium speed engines that are used in the existing LNG fueled tugs. This tug is currently in engineering phase, in close collaboration with Flag State and Classification Society. The propulsion gas engine has been fully validated within the scope of the project's demo case and is available and ready-to-use for a variety of marine applications.