Fuel consumption claims are a seductive tool for car makers and a key driver in our decision about what car to buy. But they are generally nonsense and I, for one, have always been deeply sceptical of them - hardly ever having been able to match the claims by car companies to real life driving and road testing experience. Now a new study from a British emissions engineering company - Emissions Analytics - has proven the case.
A Kia Picanto undergoes real-world fuel testing by Emissions Analytics
It has been analyzing the fuel consumption figures for 60,000 different makes and models of cars and showed the claims about fuel consumption made by manufacturers are almost never reconciled with real-life driving. In fact, only one car in the entire study to match its maker's claims is the Aston Martin Vantage, which used 21.5 miles per gallon (13.13 litres per 100 kilometres) and Aston Martin had actually reported a fuel consumption of one mile per gallon less !
The reason why Emissions Analytics data are at such variance with manufacturer's claims and other "official" figures is that the tests are carried out on the road in normal driving with conditions - with normal loads - and not in laboratories.
Only one manufacturer currently offers what it describes as transparent and honest real- world figures and that's Peugeot. It began last year to conduct tests in conjunction with an independent environment agency and a transport laboratory in France and has been publishing impressive, but not outlandish, figures since.
Peugeot is the only car manufacturer to publish what it describes as independently-verified fuel consumption figures derived from real-world driving conditions.
Even the best-performing car in the EA study - the Honda Civic - showed the difference in the company's figures and the real-world figures was 21.3 per cent. The Ford Fiesta petrol version figure claimed by Ford was 62.8 MPG (4.49 litres per 100 K)and this was shown to be actually be 37.8 MPG (7.47 litres per 100 K).
BMW's X5 has a claimed consumption of 25.4 MPG ( 11.12 litres per 100 K) but the Emissions Analytics figures show a real-world consumption figure of 16.2 MPG (17.43 litres per 100 K).
Remember the figures the next time you are looking through the small print in a car manufacturer's ad. Because the consumption figures are normally in the small print - no matter how impressive the claim.
Now you know why.
