Fuel economy figures more accurate than ever

What Car?’s True MPG testing has revealed that new official fuel economy tests are providing more accurate results than ever before.

The Worldwide Harmonised Test Vehicle Procedure (WLTP) was introduced by the European Union in September 2017 to assess new vehicle emissions and fuel economy more accurately.

The WLTP protocol replaced the NEDC type approval process that dated back to the 1970s and which was criticised for resulting in unrealistic economy claims.

What Car? compared the real-world economy figures achieved under its True MPG real-world test against official recorded figures recorded using the new, tougher-than-ever WLTP tests.

In a 15-vehicle sample that ranged from small hatchbacks to SUVs, petrols to diesels and automatic to manual gearboxes, What Car? found the manufacturer quoted economy figures were, on average, 4.9%, or 2.6mpg, higher than its testers achieved.

However, in some instances, What Car? found its real-world fuel economy results actually bettered the figures quoted by manufacturers using the WLTP guidelines.

The Mazda MX-5 2.0 184, Nissan Qashqai Tekna 1.3 140 and Skoda Karoq 1.5 TSI 150 were all more economical under real-world tests conditions than under the official figures – with the Mazda MX-5 bettering its 40.9mpg figure by 10.3%.

Other models, including the Audi Q3 35 TFSI and VW Polo TSI 95 matched their WLTP figures, but some such as the Volvo V60 D4 and Ford Fiesta EcoBoost 140, were still more than 20% down on their WLTP figures.

“For years fuel economy figures recorded under the official test regime have been almost unachievable under real-world driving conditions, so it’s great to see that the new, tougher tests have closed the gap so significantly,” said Steve Huntingford, editor of What Car?

“However, while it’s heartening to see some cars actually beating their official figures, we mustn’t lose sight of the fact the gap between official figures and our real-world tests remains, on average, at almost 5%.

“We will keep testing until that gap is gone; until then, for the most accurate fuel economy comparisons, we recommend new car buyers use our What Car? True MPG fuel tool to see what their next vehicle is likely to achieve under genuine real-world driving conditions.”