A Range-extender (REX) is like having your electric cake and eating it.
You should think of a Range-extender as an electric vehicle with the safety net of a small conventional engine, should you need to go further than the batteries will allow.
Whilst not driving the wheels, the auxiliary motor acts as a generator to charge the batteries on the move. Say goodbye to range anxiety. All you need to do with a Range-extender is charge the batteries when you get back home or to the office.
The Vauxhall Ampera and Chevrolet Volt are perhaps the best known Range-extenders on the market, but BMW also offers a Range-extender version of its brilliant i3 electric vehicle.
The technology used in a Range-extender vehicle is the stuff of electric dreams, but it’s still in its infancy and there are few models to choose from.
By way of comparison, at £33,830, a BMW i3 REX costs £3,150 more than its pure EV counterpart.