Call for switch to mpl

One in three motorists would prefer their car’s fuel economy figures to be measured in miles-per-litre rather than gallons, an AA Populus poll conducted in conjunction with Auto Express has revealed.

Of 21,450 drivers surveyed, more than 7,000 voted to ditch the traditional mpg figure, which the AA agrees is now “outmoded, confusing and irrelevant”, particularly for young drivers.

Fuel has been sold by the litre for at least two decades, but despite that, fuel economy figures are still most prominently advertised and displayed as mpg.

AA president Edmund King said: “We buy fuel in litres, yet the majority of us still think about economy in miles per gallon. These two different measures don’t add up. As fuel economy is vital to motoring today, I think it is time to break with the nostalgia of the past and begin using fuel economy figures which relate to what we buy at the pumps.”

The AA’s latest Populus poll revealed that it was younger drivers, aged 18 to 24 years, who were most in favour of that switch (51 per cent). But when it came to converting mpg into actual fuel costs at the pumps, Auto Express found motorists of all ages were confused.

When we asked 10 drivers to calculate the cost of a 20-mile round trip behind the wheel of a car achieving 45mpg – with a fuel price of 140ppl – only one motorist was able to do the sums in their head. This was the only motorist whoknew the conversion rate – roughly 4.5 litres per gallon.

When the same maths problem was posed, swapping the 45mpg for its equivalent 10 miles-per-litre, 60 per cent of the drivers quizzed at the Tesco Extra fuel forecourt in Watford, Herts, were able to quickly come up with the correct answer: £2.80.

Auto Express editor-in-chief, Steve Fowler, said: “When money’s tight, the last thing motorists need is a fuel economy measurement that is virtually impossible for the average driver to convert into real spend at the pumps.

“Our findings clearly show that motorists could easily do these sums in their head if the industry started quoting fuel economy figures in miles per litre.” By law, economy figures should actually be published in litres per 100 kilometres, according to the Society of Motor Manufacturers and Traders. However, it says motorists are confused by this metric measure, so mpg is used more prominently alongside it.

Gallons have been used for centuries, originally to measure wine and ale. But it became law to sell fuel in litres in 1988.