• Why MEPs must withdraw dirty diesel’s ‘license to pollute’

    Exactly five years after the Dieselgate scandal broke, the European Parliament is set to vote on a file that, at first glance, may look purely technical, but will in fact determine how much toxic air from exhaust pipes we’ll be breathing in the years to come. MEPs now have a second opportunity after 2016 to - finally - force carmakers to respect emission limits that were set all the way back in 2008. Far from being a big victory for clean air, however, the report adopted in the Parliament’s environment committee represents the bare minimum of what is needed. In particular, any amendments removing the clear end date of the harmful ‘conformity factors’ should be rejected.

    The damage done by air pollution to public health is well documented, but the figures bear repeating. The European Environment Agency (EEA) estimates that every year 68,000 premature deaths can be attributed to nitrogen dioxide (NO2) pollution, and diesel vehicles are the main culprits – responsible for about 75% of the health costs of road-based air pollution in the EU.

    With so many lives at stake, the vote will be an important litmus test to see whether the EU has learned its lessons from Dieselgate and is serious about the ‘zero pollution ambition’ outlined in the European Green Deal.

    So, how did we get to this situation?

    Back in 2016, in the middle of the Dieselgate scandal, rather than holding the car industry to account for their cheating and stepping up enforcement, the EU actually decided to relax pollution limits for nitrogen oxide (NOx) emissions through so-called ‘conformity factors’ (allowing cars to pollute over the legal limits), as part of the transition from laboratory to real world ‘Real Driving Emissions’ (RDE) vehicle testing.

    The Commission argued that such flexibilities were needed to take account of statistical and technical uncertainties when switching from laboratory measurements to ‘Portable Emissions Measurement Systems’ (PEMS). However, what should have been a reflection of genuine measurement uncertainties was turned into a ‘license to pollute’ after pressure from EU governments, allowing cars to emit 2.1 times over the legal NOx limit (up to 168mg NOx/km instead of 80mg/km) until the end of 2020, and 43% more (up to 114mg/km) with no set end date. This was despite the Commission’s own Joint Research Center (JRC) reporting as early as 2017 that the uncertainty of the better PEMS devices was as low as 24%.

    The conformity factors were, however, always supposed to be a temporary measure, with the Commission promising in 2017 annual downward reviews and that the conformity factors would be phased-out by 2023 at the latest. The Commission back then clearly announced that ‘car manufacturers should thus already start designing vehicles for compliance with a conformity factor close to 1 (=80mg/km NOx)’.

    Since then only one annual review slightly reduced the second conformity factors from 1.5 to 1.43, prior to the 1.5 conformity factor coming into force. Instead, in 2018, the General Court of the EU ruled, following a legal challenge by three EU capitals, that the European Commission had no right to adopt laxer pollution limits through the back door using conformity factors.

    The ruling was an opportunity for the Commission to correct its error. Instead, they appealed the Court’s decision and announced that they would propose the same conformity factors, but under a different legislative procedure. Despite this missed opportunity, MEPs now have an opportunity to have their say and vote for cleaner air.

    Leaving the politics and legal questions to one side, however, it is important to ask, is a conformity factor for the car industry still actually necessary and justified?

    The answer to that question is a resounding no. T&E looked at data published last year by manufacturers themselves and our analysis of 307 RDE test results from Euro 6d-temp and 6d diesel cars showed that 87% of the cars emitted below 80 mg/km of NOx. There can be no doubt, therefore, that the technology necessary to meet the 80mg target in real-world driving conditions exists. In fact, the data showed that already at least 59 diesels could emit levels of NOx lower than 20mg/km, giving manufacturers plenty of wiggle room to account for any uncertainty in the PEMS equipment.

    If some carmakers are finding it hard to meet legal limits in on-road tests, this is probably because they have been optimising their emissions control systems to lower costs rather than to provide adequate on-road emissions performance. Enshrining a pollution pass for manufacturers – more than 12 years after the Euro 6 limits were set in legislation – will only reward laggards at the expense of public health.

    The environment committee’s position is a strict minimum

    The review of the ‘conformity factors’ is a golden opportunity to put an end to this situation and make sure all diesel cars respect Euro 6 limits on the road. Emissions limit values, as the law defined in 2008, were always meant to be respected ‘under normal conditions of use’, and the new law should require carmakers to demonstrate that they meet the limits within the uncertainties of the test.

    The report adopted by the environment committee is the minimum needed to get there eventually, and includes three essential elements:

    • Review the conformity factors downwards now – as JRC evidence confirms the worst case uncertainty of PEMS is maximum 1.32 (and can also mean actual emissions are underestimated instead of overstated).

    • Set an end date for the conformity factors as promised by the Commission back in 2017: 2022 is eight years after limits first entered into force.

    • No more ‘conformity factors’: conformity factors were a dangerous precedent, the next Euro standard cannot include any conformity factors and must set a clear road to zero emissions.


    For more information please contact:

    Alex Keynes

    Clean Vehicles Manager

    +32 (0) 493508247