Peugeot 308

A new report compiled by Transport & Environment (T&E) has claimed that the average gap between official test results for CO2 emissions/fuel economy and real-world performance of many car models is likely to grow to 50% on average by 2020.

Entitled ‘Mind the Gap 2015,’ the report analyses on-the-road fuel consumption by motorists and highlights the abuses by carmakers of the current tests and the failure of European Union (EU) regulators to close loopholes.

According to the report, the gap has increased to 40% on average in 2014 from 8% in 2001, with new cars, including the Mercedes A, C and E class, BMW 5 series and Peugeot 308, swallowing around 50% more fuel than their lab test results.

"There must also be a comprehensive overhaul of the testing system."

As per the test procedure, conventional cars can emit between 40% and 45% more CO2 emissions on the road than what is measured in the lab.

T&E has urged the EU to clarify the causes of these big deviations as soon as possible.

T&E clean vehicles manager Greg Archer said: "This widening gap casts more doubt on how carmakers trick their customers in Europe to produce much better fuel-efficiency in tests than can be achieved on the road.

"The only solution is a comprehensive investigation into both air pollution and fuel economy tests and all car manufacturers to identify whether unfair and illegal practices, like defeat devices, may be in use. There must also be a comprehensive overhaul of the testing system."

The report states that the distorted laboratory tests are costing a typical motorist €450 a year in additional fuel costs compared to what carmakers’ marketing materials claim.

However, the car manufacturers are said to be continuing to try to delay the introduction of a new test (WLTP), originally scheduled for 2017.

Approximately two-thirds of the claimed gains in CO2 emissions and fuel consumption since 2008 is believed to have been delivered through manipulating tests with only 13.3g/km of real progress on the roads set against 22.2g/km of ‘hot air.’

The report comes a week after German automaker Volkswagen confirmed to have used a defeat device in certain models that helped it to rig the US diesel car emissions tests.

Image: Peugeot 308 allegedly swallows 50% more fuel than what it showed in lab tests. Photo: courtesy of M 93 via Wikipedia.