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Dirty secrets

26 October 2015 By Olaf Storbeck

The fierce response of U.S. regulators to Volkswagen’s emissions manipulation shows how lax European peers have been on a core public health issue. Legal limits for harmful diesel emissions are too high, test procedures are weak, and early evidence of non-compliance in real life was ignored. Clean diesel is possible, but this will dent automakers’ profits.

Europe’s long love of diesel, which enjoys tax benefits in many countries, was driven by an ambition to fight climate change: diesels burn 20 percent less fuel. Now, the technology is used in more than half of all cars sold in the European Union.

But the more fuel-efficient the engines are, the more toxic nitrogen oxide (NOx) they create. In London alone, NOx pollution causes the equivalent of up to 5,900 deaths a year, a recent King’s College study concluded. Most European cities habitually exceed the allowed NOx levels, often by a large margin. The transport sector, and diesel in particular, are mainly to blame.

Europe’s carmakers long claimed they had fixed the problem by equipping diesel with NOx traps. It’s not just VW. On average, new diesels sold in Europe in real use emit seven times more NOx than the official limits allow, a 2014 study of the International Council on Clean Transportation (ICCT), a non-government organisation, showed.

VW equipped cars in the United States with “defeat devices” that damped down emissions during lab testing. In Europe, carmakers have had no need for such tricks, thanks to the leniency of the testing regime. At 80 milligrams per kilometre, permitted NOx emissions in Europe are more than twice as high as the U.S. level. The American test protocol is also more demanding and closer to real driving. Europe’s test regime dates back to the 1990s and entails unrealistically low acceleration and engine load.

Brussels was made aware of diesel’s NOx compliance issues as early as 2013, the Financial Times reported on Oct. 26. The then-EU environmental commissioner Janez Potocnik warned his colleagues that the testing protocol might allow carmakers to game the rules. A year earlier, the European Commission declined to fund ICCT research into diesel’s real-driving emissions, the charity says on its website. ICCT’s scaled-down project in May 2014 eventually triggered the U.S. investigation into VW that uncovered the cheating.

This raises an inconvenient question for Brussels: given that more than half of all new cars sold in Europe are diesels, Europe’s high NOx pollution and its health dangers, why did the mounting evidence not trigger swift political action? After all, with diesel engines powering less than 1 percent of all new cars sold in the United States, the threat to public health in America is much smaller.

The lobbying power of Europe’s auto industry may be an explanation. German and French carmakers and suppliers – hit hard by the euro crisis – are the world’s leaders in diesel technology. And the technology to make it clean is pricey. Take the BMW X5, which was tested along with the VW Jetta and Passat by ICCT. The X5 passed the real-live test with flying colours. But while carmakers usually rely on one of two different NOx-trapping technologies, BMW is using both. This doubles additional costs per vehicle to $1,000, if not more.

Drivers, though, are not willing to pay extra for cleaner cars. Diesel cars are already more expensive to build than their petrol equivalents, but only part of that extra cost is passed on through higher car prices. An additional cost for making diesel truly clean would most likely just eat into the challenged industry’s profit margin. Encouraging drivers to switch to more profitable petrol cars isn’t an option, because from 2015 to 2021, new-car carbon emissions have to fall by 27 percent, EU regulations have decreed. Hybrid and electric cars haven’t really taken off.

Volkswagen’s shenanigans have put attention on the company’s flawed internal culture and weak controls, but equally tough questions may soon arise over Europe’s grand diesel delusion. Test procedures were already under review before the scandal erupted, and real-drive tests are likely to be made compulsory by 2017. Policymakers will be under pressure to speed up and tighten these reforms, as well as funding independent research and supervision to keep a cap on real-drive emissions.

This will be good news for people suffering from respiratory disease, but bad for carmakers’ profits. It may even make diesel engines economically unviable in smaller, mass-market cars. That’s a price worth paying for clean air and better public health.


This article has been corrected to change the unit of NOx level limits in the fifth paragraph from grams per kilometre to milligrams per kilometre.


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