Fuel economy LIE – Your car probably isn’t as efficient as you think and this is why 

Fuel economy is something that is crucial for drivers as the cost of motoring increases. 

However, it has been revealed that there is a discrepancy between the quoted and real-world fuel consumption figures. 

The International Council on Clean Transportation (ICCT) revealed that the gap between quoted and real-world emissions has increased from nine per cent to 42 per cent since 2001. 

This discrepancy translates to an average €400 per year in extra fuel costs for an average car annually. 

As a result of the gap less than half of the on-paper reductions in CO2 emission values since 2001 have been realised in practice, claim the ICCT. 

“We analysed data for more than 1.1 million vehicles from eight European countries, and all data sources confirm that the gap between sales-brochure figures and the real world has reached another all-time high,” says Uwe Tietge, a researcher at ICCT Europe and lead author of the study. 

“When we published our first study in 2013, the gap had widened over ten years from roughly 10 per cent to around 25 per cent. 

“Now it has increased to 39 per cent for private cars, and 45 per cent for company cars.”

Privately-owned vehicles fared better in the test of over 1.1 million cars by ICCT, when compared to company motoers with a 39 per cent difference compared to 45 per cent gap. 

Motorists can take some solace as these figures could well improve over the coming years due to the introduction of the Worldwide Harmonized Light Vehicles Test Procedure (WLTP).

Since September 2017, the WLTP has been introduce to more accurately reflect real driving conditions which in turn should cut the real-world gap by half. 

“But even the new test procedure contains new loopholes that could permit the performance gap to increase again in the future,” warns Peter Mock, the ICCT’s managing director, said in the statement..

“Further actions are therefore required, in particular on-road testing of fuel consumption and CO2 emissions under real driving conditions and a not-to-exceed limit for the real-world gap, as it already exists for air pollutant emissions today.”

On November 8, the EU Commissioner for Climate Action and Energy, Miguel Arias Cañete, is expected to announce a regulatory proposal for reducing CO2 emissions of new cars and vans for the 2020–2030 time period. 

It remains uncertain whether the Commission’s regulatory proposal will also include policy instruments to tackle the discrepancy between official and real-world CO2 emission levels.