Hotel electric power (HEP) is electricity generated and used by a vehicle, especially a ship or truck, for purposes other than propulsion such as climate control, communications, entertainment, lighting, refrigeration, water desalination and treatment, etc. The electrical load generated by such systems is termed the "hotel load".
In a railway contexts a passenger train uses head-end power (also abbreviated to HEP) for functions such as climate control, cooking, lighting, and water heating.
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Hotel electric power Wikipedia(Text) CC BY-SA