An automatic standby generator senses a power outage, turns on automatically, and delivers backup power to your home. Within seconds of an outage, it automatically supplies power directly to your home’s electrical circuit breaker box. After utility power returns, the generator shuts itself off and waits for the next outage. It will even run until utility power returns – whether that’s two hours or two weeks. It operates on natural gas or liquid propane gas and sits outside just like a central air conditioning unit.