It is one of the most prestigious car manufacturers in the world with a reputation for producing some of most luxurious vehicles available but now even Bentley is being forced to think green.

Sales in the US have been hit hard by the credit crunch – though engineering director Ulrich Eichhorn is quick to point out that other less prestigious brands have fared worse. Growing sales in Brazil, China, Russia and India have helped, expected to total around 1,000 this year, but America is still the largest market for Bentley accounting for around 40 per cent of its total sales.

However, the weakness of the US dollar means that Bentley is actually making less money on the sales of its cars Stateside than anywhere else.

All of this has led to a renewed focus on green matters.

Eichhorn said: “Over the past five years we have reduced CO2 emissions by 60g/km – a 15 per cent reduction. And we will reduce this by a further 15 per cent up to 2012.”

From there, more radical developments are planned.

“We will introduce a powertrain that is 40 per cent more efficient than those we use today – without any sacrifice in performance or refinement. We’re not talking about it yet, but it will be in the market by 2012,” continued Eichhorn.

“The third leg of our low-CO2 strategy is that all our cars must, by 2012, be compatible with renewable fuels – and that has to mean renewable biofuels of the second generation.”