Cold Ironing

Cold Ironing is the process of providing shore-side electrical power to a ship at berth while its main and auxiliary engines are turned off. Cold ironing permits emergency equipment, refrigeration, cooling, heating, lighting, etc. to receive continuous electrical power while the ship loads or unloads its cargo. A ship can cold iron by simply connecting to another ship's power supply; a process the US Navy has practiced for many years, or from a shore-side power source. Recently cold ironing has been looked to as a means to mitigate air pollution by significantly reducing, and in some cases, completely eliminating harmful emissions from diesel engines.

History

Cold ironing is a shipping industry term that first came into use when all ships had coal fired iron clad engines. When a ship would tie up at port there was no need to continue to feed the fire and the iron engines would literally cool down eventually going completely cold, hence the term "cold ironing".