A new propulsion concept allows workboats and tugboats to benefit from flexible hybrid propulsion without installing a gearbox or additional electrical components.
The new arrangement is based on Schottel’s recently developed Y-Hybrid thruster technology. This allows port and starboard azimuth thrusters to be connected, meaning that both can be driven by either of the main engines.
Svitzer, the global tugboat operator owned by Maersk, has been involved in the design of the new concept. The companies are discussing a pilot installation on one of Svitzer’s 430 vessels.
The conventional hybrid arrangement for tugboats involves at least one power source (diesel engine and/or electric motor) for each thruster. Using the Sydrive-M, the flexibility of a hybrid arrangement can be achieved without the addition of gearboxes or electrical components. This arrangement means that owners can select a hybrid configuration without altering their existing vessel design.
The hybrid configuration allows many permutations depending on operational mode. In light operation or free sailing mode, when full power of both engines is not needed, one of the two main engines remains alternating off - reducing the operation hours of the main engines, with an equivalent reduction in maintenance. This mode also means that the working engine is more optimally loaded than two engines working at relatively low load in a conventional set-up.
In fire-fighting mode, the disengaged main engine is used to drive the pump through its front power take-off, with no requirement for dedicated engines or extra clutches and controllable pitch propellers. In full thrust operation, the connection between the two thrusters is disengaged and each engine is engaged to a thruster.
Sydrive-M can be integrated into any common vessel design with direct propulsion with no need of design changes. It is available for Schottel’s Rudderpropeller and EcoPeller series of azimuth thrusters from 1,000kW up to 3,000kW.