What Car? says...

As a general rule of thumb, mid-engined exotica and environmentally friendliness go together like a room full of lambs and a very hungry wolf. It is, however, possible to get yourself a flash set of wheels while giving the Earth a nice big hug – introducing the BMW i8 Roadster.

This striking slice of futurism combines a dinky 1.5-litre three-cylinder engine with batteries and an electric motor. The result? Heart-pounding acceleration, with CO2 emissions of just 46g/km. Like the i8 Coupé, it has a super-stiff carbonfibre-reinforced plastic passenger compartment to ensure the car doesn’t behave like a microwaved lettuce leaf.