Hotel electric power (HEP) is electricity generated and used by a vehicle, especially a ship, truck, submarine or some turbo prop aircraft without APU generator for purposes other than propulsion such as climate control, communications, entertainment, lighting, refrigeration, water

desalination Desalination is a process that takes away mineral components from saline water. More generally, desalination refers to the removal of salts and minerals from a target substance, as in Soil salinity control, soil desalination, which is an issue f ...

and treatment, etc. The electrical load of such systems is termed the "hotel load". Not having a separate auxiliary power unit saves weight in turbo-prop aircraft such as the ATR 72 and

ATR 42 The ATR 42 is a regional airliner produced by Franco-Italian manufacturer ATR, with final assembly in Toulouse, France. On 4 November 1981, the aircraft was launched with ATR, as a joint venture between French Aérospatiale (now Airbus) and ...

, where a propeller brake is used to allow the turbine to continue running without the propeller spinning in "hotel mode". In a railway context a

passenger train A passenger train is a train used to transport people along a railroad line. These trains may consist of unpowered passenger railroad cars (also known as coaches or carriages) hauled by one or more locomotives, or may be self-propelled; self pr ...

uses head-end power (also abbreviated to HEP) for functions such as climate control (heating and air conditioning), cooking, lighting, and water heating.

See also