Although the royal family of Great Britain may not have the authority to decree any initial steps, eco-friendly or not, however, they still hold sway over much of the public opinion and have made the cause of environmentally-friendly motoring their very own.
Going after the lead of her son and successor Charles, the Prince of Wales, whose Aston Martin was modified to accept power by old wine and whose Audi, Jaguar and Range Rover transformed to be powered using used cooking oil, Queen Elizabeth II is also converting her custom Bentley limousines to be powered by bio-fuels.
Based on the Arnage, the State Limousine by Bentley is however individually-crafted in-house by the company's coach-building division of Mulliner.
Only two vehicles were ever produced with a price in excess of $14 million per car, one of which was given as a present to Her Majesty during her Golden Jubilee way back in 2002, while the other was specially made by the crown to serve as a back-up.
The 4-ton armored vehicles, faithfully preserved by Bentley, are propelled by the firm's recurrent 6.75-liter V8 which is able to generate about 400 horsepower, and will be altered to use bio-fuel.
Bentley has commented that the royal family is a staunch backer of Crewe's initiative to change to bio-fuels, as Bentley targets that by the year 2012 all its versions will have the capacity for accommodating flex-fuel.