What Car? @ the Future Car Challenge - Vauxhall Ampera

Car: Vauxhall Ampera
Technology: electric motor with a petrol engine as a back-up generator
Range: 350 miles
On sale: 2012
Driven by: Steve Huntingford
What Car? road tester

Most electric cars have less range than a Vuvuzela. However, when the Vauxhall Ampera's batteries are flat, a 1.4-litre petrol engine kicks in and generates more electricity. It's not a hybrid like the Toyota Prius, though, because it's always driven electrically.

The idea is that you charge the Ampera overnight at an off-peak rate – it takes around three and a half hours – and can then drive for about 40 miles on battery power. If you need to go farther then the petrol engine gets to work, allowing you to cover over 300 miles more.

This innovative system makes the Ampera cheap to run and extremely green (assuming the electricity doesn't come from a coal-fired power station). Vauxhall reckon it averages a whopping 175mpg and emits just 40g/km of CO2.

Don't think you have to change your driving style when you're behind the wheel of the Ampera, though. There are no gears because electric motors develop their maximum torque from standstill, but aside from this – and the fact that there's no engine noise for the first 40 miles – it feels like a normal car.

It's smooth and effortless around town, and can keep up with the flow of traffic on faster roads. There's even a sport button that sharpens up the electric motor's responses in case you need an extra burst of speed.

Highlight of the car The way the batteries are partially recharged when you apply the brakes because it means the engine can cut out again when you're in stop-start traffic.

Highlight of the day Seeing What Car?'s used car editor, Matt Sanger, driving with his door mirrors folded in to ensure he got the absolute maximum mpg.