A steam generator, in the sense of an auxiliary boiler on a ship, is a form of boiler. It uses high-pressure superheated steam from the main steam supply[1] used for propulsion, and uses this to generate low pressure saturated steam. This is then used to power auxiliary steam engines around the ship such as winches or pumps, or to supply any steam requirement on the ship that does not require high superheating, such as boiler feedwater and freshwater evaporators.