Hotel Electric Power is a maritime term referring to electricity generated and used aboard a ship for purposes other than propulsion such as lighting, communications, climate control, refrigeration, water desalination and treatment, entertainment, etc. The term has also been applied in railway passenger train usage meaning lighting, climate control, water heating, cooking power, etc. In the USA however, the same definition with the same initials (HEP) is generally understood to stand for Head End Power

Head end power

Head end power or electric train supply is a rail transport term for the electrical power distribution system on a passenger train. The power source, usually a locomotive at the front or “head” of a train or a generator car, generates all the electricity used for lighting, electrical and other...

.