Prince Charles has given drink-driving a whole new twist, by converting his Aston Martin DB6 to run on surplus English wine.
The 38-year-old car, given to Charles on his 21st birthday, has been modified to run on 100% bioethanol as part of a number of measures to reduce the Prince's carbon footprint.
The Prince's chief aide, Sir Michael Peat, said: 'Charles travelled only two or three hundred miles a year in the Aston, but he wanted it to be environmentally friendly. It just happened that our bioethanol supplier makes the fuel from surplus English wine.'
The car averages 10 miles a gallon, the equivalent of 4.5 bottles of wine for every mile.
At 1.10 a litre, the bioethanol is only slightly cheaper than conventional petrol, but it's estimated to produce 85% less carbon dioxide.
The grapes used for Charles's fuel have already been fermented into wine on a vineyard near Swindon, Wiltshire.
Its owners bottle all they can, but cannot produce more than their EU quota. Rather than destroy the excess, the vineyard now sells it to the Gloucestershire biofuels supplier Green Fuels, where it is distilled.
The green Prince has also introduced a number of environmentally friendly measures at his homes, which include feeding his cows on grass rather than grain to cut their flatulence and minimise their emission of the greenhouse gas methane.