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Why the VW #DieselGate Is Only the Tip of the Iceberg, Part 3

How U.S. regulations brought results where Europe failed

Will the VW scandal change testing systems for good?

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


As a rollercoaster year for the automotive industry comes to a close, the effects of the VW #DieselGate continue to be felt. In Part 1 of this blog series, I presented the case for why this was not limited to diesel nor Volkswagen, and in Part 2, just a month later, the scandal had indeed widened. In Part 3, the question is: why exactly were American regulators able to uncover this scandal where Europeans failed? Why is the US EPA better set up to catch cheating, and how can Europe improve?

As the scandal continues to widen – now encompassing Porsche – American regulators are moving on state and federal levels to file lawsuits against VW and assess potential damages due to American consumers. But why was it the US – a country with very few diesel cars – that uncovered the scandal?

While American regulators stepped in at a crucial stage, it should be noted that it was the NGO ICCT that first raised a red flag, yet the question remains: why had this not been uncovered sooner in Europe, where in some countries diesel cars account for more than half of all vehicles?


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The testing vehicle that started the whole thing. Image credit: University of West Virginia.

The testing vehicle that started the whole thing. Image credit: University of West Virginia.

On a fundamental level, American regulators are more independent than European ones. For example, almost 70% of funding for automotive certifying agencies in the UK come from industry itself. While automotive trickery has long been an open secret in industry, in the US action is finally being taken to address the issue head-on. The California Air Resources Board (CARB) is one such key player who took forward emissions testing started by ICCT, and once results were substantiated and repeated, VW was confronted with the data.

In fact, on one level, the reason VW was not caught cheating in Europe, is because it does not really need to. The emissions test procedure is considered so out-of-date and easy-to-fake, that the results are surprising only to outsiders.

According to Mike Hawes who heads the UK Society of Motor Manufacturers and Traders, the American system does tests in strict conditions with an independent approval agency, appointed by the government rather than industry itself. In addition, carmakers have to comply with 31 mg of NOx emissions per km, whereas in Europe that number is 80 mg, so it is clearly easier to sell a diesel vehicle in the EU compared to US requirements.

Finally, European tests are done in labs using an out-of-date drive cycle, far from reflecting real on-road conditions. Not to mention, diesel vehicles tend to – pardon the lack of technical language – ‘gunk up’, and are therefore not performing at their stated level just a year or two after being sold as new and ‘clean’.

As discussed in Part 2 of this series, the scandal includes fuel economy gaps as well. According to recent research, motorists in the UK pay up to 2,800 Euros more than they should due to a gap between stated and actual fuel economy. This is partly due to loopholes, which are duly exploited by automakers in the current regulatory regime of Europe.

So what comes next? Either Europe updates its outdated system (something industry even says it wants), or it continues to deal with pollution in a knee-jerk fashion: Rome and Milan just banned cars outright on certain days and hours.

In the fourth and final part of this series, I will look at whether or diesel cars are really ‘dead’, and what this all means for the future of electric vehicles.

Tali Trigg is an energy analyst, technology policy advisor and writer. His work includes research and analysis on energy and transportation, with an emphasis on the role of cities in shaping transport energy demand and mobility solutions. His blog covers the wide range of mobility and energy, with deep-dives into numbers and maps, but is keen to cover anything transport-related and under-reported. Opinions are his own.

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