Official fuel economy figures might not be as reliable as you think

Can we really trust official fuel consumption and CO2 emissions figures for our next car?
Written by Charlie Osborne, Contributing Writer

Can we really trust official fuel consumption figures?

Perhaps not. According to the latest report released by Transport & Environment and later reported by the BBC, there is a widening gap between official methods of recording fuel consumption and CO2 emissions of vehicles in comparison to real-world testing.

Whether it be adjusting tyres to reduce resistance, tweaking breaks or altering the body of the car itself to lower air resistance, these subtle methods can be employed when faced with now compulsory fuel economy tests. However, current "lax" procedures are allowing car makers to achieve "unrealistically low results" and the New European Driving Cycle (NEDC) test can be manipulated and controlled, according to the report.

The data is used by multiple parties, including European regulators, governments, and consumers who are environmentally and financially conscious. However, if car makers are constantly outsmarting the system, there is no guarantee that official figures are anywhere close to the truth. The "growing gap between what drivers achieve and what the tests really say about fuel economy and emissions" is reflected in EU statistics which say average CO2 emissions fell by roughly 30g/km between 2001 and 2011, whereas real-time data gained from German motorists suggests that the truth is closer to a loss of only 10g/km.

The report suggests that current supervision of testing and checks on production vehicles -- in order to make sure they are equivalent to tested vehicles are "inconsistent and inadequate," as manufacturers pay companies carrying out the tests -- and of course, wish to look as clean and economic as possible.

As a result, Transport & Environment believes the current system needs updating urgently to strip manufacturers of the ability to manipulate tests and to give consumers more realistic indicators of vehicle fuel economy and CO2 emissions. The report states:

"Carmakers are misleading their customers by promoting fuel efficiency figures that they know will not be achieved."

Image credit: Jeff Turner


This post was originally published on Smartplanet.com

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