2. Energy-propulsion architectures. The naval architect's point of view

2.1 Mechanical propulsion families

The thruster or thrusters are driven by a thermal machine:

• direct drive by slow-speed diesel engines is the propulsion method systematically adopted on large cargo ships, with unit powers of up to 80 to 90 MW at less than 100 rpm, propellers with fixed blades;

• semi-fast diesel drive, via a reduction gearbox, is the most widespread propulsion system. With one or two thrusters, one or two engines per shaft line, it covers all the needs of the world...