When used as a conventional hybrid electric vehicle, a computer selectively operates between the engine and the electric motor – or even both at the same time – depending on the level of power required to travel.
When it’s operating in electric mode, the vehicle is driven only using the electric motor until the charge from the high voltage battery becomes too low, at which point it reverts to the hybrid mode automatically. Pure electric mode gives you up to 32 miles of zero tailpipe emissions, depending on your driving style and road conditions.