What good might come from the VW emissions scandal?

As part of the continued fallout from the VW emissions scandal, including VW Group CEO Dr Martin Winterkorn stepping down from his post, a number of senior government figures and bodies are calling for changes to the regulations so that tests cannot be rigged again.

Those within energy and transport ministries in the UK, France and Germany - along with those at the top levels of government including German Chancellor Angela Merkel - are stating that thorough investigations will be carried out to make sure that stated emissions levels are correct.

Except the problem is that official emissions figures are never correct when compared to real-world driving, and the calls for more accurate testing are getting louder as news filters through that the scandal is spreading rapidly.

What is significant is that a real-driving emissions (RDE) test is already confirmed to come in to force as of 2016. What this will do is test cars using a portable emissions measurement system attached to the vehicles, which are then driven around a standardised route, rather than the current rolling road that is currently used.

What is even more significant is that the International Council on Clean Transportation (ICCT) - an independent non-profit environmental transport organisation - along with the ADAC - Germany's equivalent of the AA and RAC - carried out NOx tests on the latest batch of diesel engines from a number of manufacturers and published its report earlier this month (3rd September). It carried out tests using the current test cycle (the New European Driving Cycle) which is well recognised as being fundamentally flawed in terms of accurate emissions testing. The group also tested diesel vehicles using the forthcoming and more realistic WLTC (Worldwide Harmonised Light Vehicles Test Cycle), along with carrying out its own real-world tests.

The conclusion from the tests state that: "the biggest challenge for diesel passenger car manufacturers will not arise from the laboratory test under the certification cycle (be it the NEDC or the WLTC), but from the impending real-driving emissions (RDE) test". Worrying reading for the bosses of car manufacturers.

It goes on to say: "Under this new testing framework, diesel passenger cars will have to prove that they can keep NOx emissions at reasonably low levels during an on-road test that more closely represents real-world driving situations. As demonstrated in a recent ICCT publication (published in late 2014), this is frequently not the case for the current generation of Euro 6 diesel passenger cars."

That earlier report showed that the levels of NOx being emitted under real-world driving conditions are decreasing as increasingly stringent European emissions levels come into place - a real-world drop of 40 per cent from 1 g/km NOx at Euro 3 limits in 2000 to 0.6 g/km NOx at Euro 6 in 2014. However, the official limits were 0.5 g/km and 0.08 g/km respectively. This sees a shift between official and actual limits from double the legal limit to 7.5 times the amount. The manufacturers must have passed the official limits and satisfied the regulators or else the cars could not have been sold with that type of engine in place. Therefore, either the manufacturers are cheating the tests in a similar fashion that VW has in the United States or, the more likely option, the tests have no real bearing on discovering how polluting the cars actually are.

The ICCT report goes on to conclude: "NOx emissions from diesel passenger cars are not properly controlled under the current, NEDC-based testing framework. What those results do indicate is that the current NEDC testing framework is insufficient to ensure that Euro 6 vehicles have acceptable NOx emissions under real conditions of use, and that the new RDE regulations are fully justified and much needed. Since RDE cannot apply retroactively to existing Euro 6 type-approval certificates, it is essential to act fast and ensure that additional high emitters of NOx are prevented from entering the market."

So how much of an impact will the RDE test have on the car industry? Well for those who would like to see fireworks as manufacturers fail emissions tests as soon as the RDE kicks in, you will unfortunately be a little disappointed. The test will be phased in and the first 20 months will be a monitoring period when no on-road emissions limits will be enforced. After that, from September 2017 onwards, the first step will see manufacturers allowed to sell cars that emit up to twice the Euro 6 NOx limit of 0.08 g/km. This is the first time since the Euro standards were introduced where the practical emissions limit will be raised instead of lowered, showing just how redundant the current tests are in terms of real-world driving. Finally, the second stage of introducing RDE is likely to appear around 2019 and should bring the limit close to the current 0.08 g/km NOx, making todays current limit more applicable. This phased introduction should prevent the need for manufacturers to write-off potentially large amounts of their range as they work towards RDE testing limits.

It must be said that the real-world tests carried out by ICCT and ADAC were on European models and using European test cycles, and the device defeat software was discovered in America. There is no current evidence to show that the VW Group has used the software to rig emissions results in Europe and, despite VW revealing that 11 million vehicles could be involved, it is not yet clear how many of those have used the software to cheat the tests. Potentially the less stringent emissions regulations of Europe have made the device defeat software redundant and it is just the US tests that triggered the system. We don't know yet, though it is surely a only a matter of time before we do. The different way tests are carried out in Europe could mean that enough of the loop holes are already closed off, but if the current emissions issue shows us anything, it is that greater vigilance is clearly needed across the board and an overhaul of the system is imminent.

What must happen is that the RDE tests have legislation that ensures the current emissions rigging scandal cannot take place again. It is excellent news that current emissions standards are becoming stricter and more accurate, but if manufacturers can cheat the system again, than the new tests are as useless as they currently are. Dr Winterkorn is a well-respected figure in the automotive industry and his resignation shows just how bad the state that the VW Group has gotten itself into. The industry is balancing on a knife point at the moment and it will only take one more manufacturer to be discovered to have cheated emissions tests, to topple what is already one of the largest scandals in automotive history over the precipice and into full-scale catastrophe. If nothing else, one certain benefit is that that the increased scrutiny from the public, governments and the industry brought about by the issue will ensure that emissions test procedures will never be ignored to the same extent again.

Reported emissions figures from the ICCT's NOX control technologies for Euro 6 Diesel passenger cars - market penetration and experimental performance assessment.

Chris Lilly

Author:Chris Lilly
Date Updated:23rd Sep 2015

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