How green is your car? - Is buying British greener?

Yes, because the car doesn't have to be shipped half way across the world in a car transporter, but the difference isn't as much as you might think over the course of a car's entire life.

Take, for example, the fuel cost of shipping a car from, say, Asia to Europe. A car transporter burns 50 tonnes of fuel per day on the 25-day voyage from Asia to Europe - that's 1250 tonnes of fuel. Since a ship carries 6300 cars, that's 198kg of fuel for each car.

In car terms, that's four-and-a-half full tanks of fuel in a typical family car equipped with a 60-litre tank. At 35mpg, that will get you 2100 miles.

So the fuel used in shipping a car from Asia to Europe is equal to about a sixth of what you'd use in a year and 12,000 miles. However, over the car's life, perhaps 150,000 miles, that's about only 1.5% of the fuel used.