3 Jul 19

Euro 6d and 6d-temp: RDE conformity factors to remain

The general discrepancy between NOx emissions measured in real life and those measured in lab conditions, which surfaced with dieselgate, led to new emission regulations in Europe.

Together with WLTP, the new lab test cycle, Europe introduced the RDE (Real Driving Emissions), a road test involving a portable emission measurement system to ensure NOx emissions in real life no longer deviate dramatically from lab-measured emissions.

So far, so good. But in 2016, the European automotive lobby convinced the European Commission to vote an amendment to the Euro 6 standard allowing NOx emissions measured during the RDE test to deviate 110% from the ‘lab’ limit. This deviation, or “conformity factor”, would apply between September 2017 and September 2019 on the pretext of giving car makers enough time to adjust their technology to the new RDE type approval procedure.

Commission exceeded its powers

Last December, the General Court of the European Union ruled the Commission had no such power. It judged the so-called “conformity factors” should not have been adopted via comitology procedure, but via ordinary legislative procedure.

The Commission lodged an appeal against the General Court judgement in February 2019 on the grounds that it disagrees with the Court's legal assessment that the Commission exceeded its implementing powers.

To avoid legal uncertainty on the type approvals granted since September 2017 – when the RDE test procedure became mandatory – the Commission now proposes to reinsert the same conformity factors into the legal text. The Commission is tabling the legal proposal via the ordinary legislative procedure, as requested by the General Court. The Commission thereby acts to ensure the necessary legal certainty for national authorities, industry and consumers.

Consequences for car manufacturers and legislation

Once adopted by the European Parliament and the Council, the Regulation will be directly applicable in all Member States.

Car manufacturers are likely to be relieved as the Commission confirms its intention to stick to the conformity factors. In the opposite case, they would have needed to step up their game and invest in better, more expensive NOx reducing technologies.

Still, research by ADAC and other organisations shows that many OEMs are already perfectly capable of meeting the NOx limits during RDE tests, raising questions about the necessity of the conformity factor.

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Authored by: Dieter Quartier