The only car which can deliver on its advertised fuel economy is the 430bhp Aston Martin V8 Vantage, according to a new study from a leading testing company.
Emissions Analytics undertook an extensive study, subjecting 60,000 different cars to new ‘real world’ consumption tests in order to assess how accurate their advertised economy figures are.
The results, which were published earlier this week, found that thousands of car buyers are being misled by factory figures, which are calculated under strict laboratory conditions.
Huge gap between claimed and real-world figures
Several cars from popular manufacturers like Fiat were found to have a 45 per cent discrepancy between claimed economy figures and those achievable under real-world conditions.
Other popular cars from the likes of Ford, Toyota, Peugeot and MINI were found to have gaps between what the manufacturers claim and what you can get of around 40 per cent.
The only car to produce better fuel efficiency in real-life conditions was the V8-powered Aston Martin, which returned 21.5mpg according to Emissions Analytics: five per cent higher than advertised.
Honda Civic the best mileage of any car tested
Honda’s Civic returned the best mileage of any car tested by the firm, returning 61.8mpg in the real world, though this still falls short of its official advertised mileage of 78.5mpg.
From 2017, a new test will come into force which will still be based in a laboratory, but which aims to more accurately assess the true potential of a car’s consumption and emissions claims.
Nick Molden, CEO of Emissions Analytics, said that the current test has encouraged the uptake of smaller engines, which the figures say have the biggest gap between official claims and actual performance.
New 'real world' test to be introduced next year
He said: “A little one litre engine will do very well, often 80MPG, on the official test, but that has no hills, no passengers, no operating air conditioning. So they suffer disproportionately when you put some weight in the boot and take it up a hill - it is basically underpowered.
“The Aston Martin Vantage is the opposite: it is overpowered. It does badly in the lab test and on the road it doesn’t do any worse. It has just got more power than you could possibly need for normal driving.”
