Click above to view the Bentley State Limousine in our hi-res gallery

Britain's royal family may not have the power to legislate any new initiatives, green or otherwise, but the heads of state still wield influence over public opinion and have taken up the cause of environmentally-conscious motoring. Following the lead of her son and heir Charles, the Prince of Wales – who had his Aston Martin converted to run on old wine and his Range Rover, Jaguar and Audi to run on discarded cooking oil – Queen Elizabeth II is having her bespoke Bentley limos converted to run on bio-fuels.

The Bentley State Limousine is based on the Arnage, but custom-crafted in-house by the company's Mulliner coachbuilding division. Only two were ever made, at a reported cost of over $14 million a piece, one of which was presented as a gift to Her Majesty upon her Golden Jubilee in 2002, while the second was commissioned by the crown as a back-up. The four-ton armored vehicles, continuously maintained by Bentley, are powered by the company's perennial 6.75-liter V8 producing 400 horsepower, and will be converted to run on bio-fuel. Bentley says the royal family are big supporters of Crewe's initiative to switch to bio-fuels, as Bentley aims to offer all its models with flex-fuel capacity by 2012.

Related Gallery2002 Bentley State Limousine

[Source: The Daily Mail via Luxist]