Rolls-Royce Receives AIP For Hybrid Tug Propulsion System

Rolls-Royce received Approval in Principle (AIP) from classification organization ABS for its novel hybrid propulsion system for tractor tugs.

The AIP was granted following an evaluation of the world’s first hybrid tug, a unique vessel designed by Jensen Maritime and which Nichols Brothers Boat Builders will deliver to Baydelta Maritime LLC in February 2019. The vessel will be the first tug boat installed with the Rolls-Royce hybrid propulsion system.

ABS considers the Rolls-Royce hybrid system is, in principle, compliant with ABS Rules for Building and Classing Steel Vessels Under 90m (2018); ABS Advisory on Hybrid Electric Power Systems (2017); and ABS Guidance Notes on Review and Approval of Novel Concepts.

The Rolls-Royce Hybrid Propulsion System consists of Power Take-In (PTI), electric motors, and main propulsion engines connected to Rolls-Royce azimuth thrusters, allowing vessel to operate in either a diesel-mechanical, diesel-electric or boost mode configuration.

Atle David Monsen, Rolls-Royce VP Sales, Integrated Ship Systems added: “Deep system integration between engines, electrical equipment, thrusters and automation systems is crucial in hybrid vessels. The Approval in Principle from ABS helps confirm the safety and functionality of the Rolls-Royce hybrid tug concept. With Rolls-Royce as a system integrator the risk and complexity for both owner and yard is significantly reduced.”

Rolls-Royce will supply all electric motors, shaft generators and a power management and control system. The hybrid arrangement provides power to US255 azimuth thrusters with ducted fixed pitch propellers that can be rotated 360 degrees around the vertical axis. This arrangement optimizes omni-directional thrust and maneuverability as well as providing improved crash stop capability.