Do I need gas in the tank? You should never drive Prius Prime without gasoline in the tank. While, under certain conditions, you may drive on electricity alone, the vehicle always requires gasoline to operate properly.
Toyota's Prius, as well as the similar Lexus HS 250h sedan, will run on battery power even if it runs out of gas, but not for long. With a strong charge prior to the gas tank hitting empty, some owners have reportedly been able to drive several miles without gasoline.Dec 7, 2016