Who says luxury car makers aren't heeding environmental concerns? Bentley will introduce its fastest, most powerful model, which bizarrely also happens to be its greenest, at the Geneva motor show in March.

The Continental Supersports develops 621bhp, accelerates to 60mph in 3.7 seconds and has a top speed of 204mph, and yet it marks Bentley's first FlexFuel model, as it can run on both petrol and biofuel. Bentley plans to make its entire range compatible with renewable fuels by 2012.

It will go on sale here in the autumn, with prices announced nearer the time, but as it sits "at the pinnacle of the Continental range", don't expect much change from £150,000. It will be able to run on petrol, E85 biofuel (a mixture of 85 per cent bioethanol and 15 per cent petrol, available from Morrisons) or a mixture of both from launch.

A Bentley engineer said: "A sophisticated fuel-sensing system ensures that power and torque remain constant irrespective of the fuel ratio to deliver seamless power delivery in the Bentley tradition."

Underneath the bonnet sits the company's six-litre, twin-turbocharged W12 engine mated to a revised ZF "Quickshift" six-speed transmission that cuts the shift time by 50 per cent and enables double downshifts. A measure of the speed on offer is the carbon ceramic brakes, which are the largest and most powerful ever fitted to a production car. Overall, the Supersports has lost 110kg compared with its GT Speed sister model.

OK, so it's not going to save the world: petrol-only consumption figures are still an eye-watering 11.5mpg on the EU Urban cycle, with CO2 emissions of 388g/km, and you can probably count on one hand the customers who will bother filling it with E85 biofuel, so it might seem like a two-fingered salute to the environment, but it's the faintest of nods in the right direction for one of Britain's luxury car makers and, let's face it, a 1.3-litre diesel engine isn't really an option.

by:telegraph