Say what you want about the British royal family, but at least one of them is trying to be responsible about the type of fuel he uses to get around. Heir to the throne, Prince Charles, reportedly drives a 38-year-old DB5 Aston Martin that’s powered almost entirely by wine- and cheese-derived bioethanol.

How is that even practical? Well, it’s thanks to the incredible amount of surplus wine being produced throughout Europe, because wineries simply have too many grapes to cultivate and not enough customers. Back in 2008, the amount of surplus wine that couldn’t be exported because it was too low-grade for the foreign market was estimated to be around 18.5 million hectolitres (1 hectolitre = 100 litres).

In desperation, a Gloucester-based winery sold 8,000 litres of surplus white wine to local biofuel producer, Green Fuels, for 1 British pound per litre - which is crazy cheap - and all of this was turned into ethanol.

"By boiling off the wine's 11 percent alcohol, condensing it and removing any remaining water, Green Fuels ended up with hundreds of litres of 99.8 percent pure ethanol, which they topped up with alcohol extracted from fermented whey collected from local cheesemakers," Ian Sample reported for The Guardian at the time.

Aston Martin had been in contact with Prince Charles about running a car on the more environmentally friendly option of biofuel, so the car manufacturers rejigged his DB5 to handle the different type of juice. "A tune of the Aston's carburettors to allow more fuel into the engine, and it was ready to go, on a mix of 85 percent ethanol and 15 percent petrol,” says Sample.

And yes, the DB5 just so happens to be James Bond's car in Goldfinger, although I doubt the British spy has the time or the staff to source the nearest biofuel producer.

While anyone with a car can follow suit and have it converted into wine-mobile, you’re going to have to know a good bioethanol supplier (the Prince gets what the Prince wants) or make it yourself, and as James Hygate at Green Fuels told The Guardian, the latter isn’t exactly idea:

"You would need an awful lot of corked wine to make enough fuel to get anywhere. The best way to produce ethanol on any scale is to effectively brew beer and distil the ethanol out, but with the licensing and health and safety issues, it's not something we'd recommend people do at home. You're producing something that's extremely flammable."

Having hitched his proverbial wagon to biofuels back in 2008, Prince Charles proved to be way ahead of the curve, with alternative fuel sources only just starting to poke their heads up and into the mainstream now.

Earlier this year we reported that a bus fuelled by cow manure broke the land speed record for a public service bus in England, and car manufacturing giant Audi not only invented a carbon-neutral diesel fuel made from water, carbon dioxide, and renewable energy sources back in April, but a month later they announced the development of another new type of petroleum-free synthetic fuel, which they’re calling 'e-benzin', produced by converting corn-derived glucose - a renewable source of biomass sugar - into isobutane gas.

Electric cars seem to be the most promising option we have right now when it comes to ditching gasoline, but let's not discount biofuels just yet. If it's good enough for a prince...