It is certainly a vintage vehicle. And now Prince Charles's beloved Aston Martin DB6 is running on vintage too. A nice little white from a vineyard in Wiltshire, to be precise.

As part of cutting his carbon footprint, the prince has converted the 38-year-old classic car - a 21st birthday present from the Queen - to run on 100 per cent bioethanol fuel distilled from surplus British wine.

Aides said this was partly due to the pattern of Royal trips set by the Foreign Office. He has now doubled the target to a 25 per cent fall in emissions by 2018.

The car - which is kept at Highgrove and clocks up just 300 miles a year - averages ten miles a gallon, the equivalent of 4.5 bottles of wine for every mile.

At $2.20 a litre, the bioethanol is only slightly cheaper than conventional petrol, but is estimated to produce 85 per cent less carbon dioxide.

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