Real-World MPG Off 25 Percent from Official Estimates: Study

Real-World MPG Off 25 Percent from Official Estimates: Study

According to a recent study by the International Council of Clean Transportation (ICCT), official and “real-world” fuel consumption and CO2 emissions for passenger vehicles had an average discrepancy of 25 percent in 2011.

That value spikes from less than 10 percent in 2001 and could add even more pressure to reform vehicle testing procedures in both America and Europe. The report showed that German automakers had the biggest divergence, with BMW’s reported emissions figures an average 30 percent lower than what was found during actual use. ICCT claims that its data comes from nearly half a million private and company vehicles across Europe.

The second widest disparity came from Audi showing a 28 percent difference while Mercedes was third at 26 percent. Toyota vehicles were found to have around 15 percent less than reported figures. It has been shown in the past that automakers are able to lower fuel use and emissions in laboratory tests by manipulating variables such as unrealistically smooth driving surfaces and using tires with extra traction.

Most recently, Hyundai and Kia have had to pay out due to its inaccurate mpg claims and Ford has been under fire in America for its hybrids. A report from the study is available for download here.

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