Shaft generator

A shaft generator is an electrical machine driven from the main propulsion engine, usually through a power take-off on the reduction gear or at the shaft, that supplies the ship’s electrical load at sea so the auxiliary diesel generators can be stopped. It exploits the better efficiency and cheaper fuel of the main engine. Constant-frequency output needs either a constant-speed (CPP) shaft or a frequency converter, and a power-take-in mode can reverse it to boost propulsion.