WLTP & RDE to cause serious production bottlenecks

The WLTP and RDE are expected to cause serious bottlenecks for OEMs, which are struggling to get all of their cars type-approved in time, i.e. before September 2018. The RDE (Real Driving Emissions) test requires them to take every single model with every single powertrain on public roads for emission assessment.

Moreover, petrol engins now need particulate filters to comply with the latest Euro 6d-temp emission standards, requiring extra engineering and development. BMW, Renault and Volkswagen have expressed their deepest concern with European authorities, according to Automotive News Europe.

Suspended production, especially petrol engines

BMW is one of the first car makers to 'convert' its line-up to WLTP. It recently announced it plans to take a number of versions of the X1, X2, X5, X6 and 7 Series temporarily out of production in June. A spokesman for the German brand confirmed the news during an interview with the German magazine Automobilwoche: "Depending on the version of the model and its volume, the interruption could last between a couple of weeks and a few months".

Ironically, the measure mainly affects petrol versions, and not the diesels. To comply with the latest emission standards (Euro 6d-temp), petrol engines have to be equipped with soot filters for the firs time – in this case called OPF, for Otto Particulate Filters, and that creates an extra bottleneck. Since diesel engines already have this technology since Euro4, they are easier to adapt.

Petrol not cleaner than diesel

Petrol engines are believed to be clean alternative to diesels, because they emit less particulate matter (PM) and nitrous oxides (NOx). That used to be the case until about 15 years ago, when many OEMs introduced diesel-like direct injection technologies to their petrol engines. High-pressure direct injection increases fuel efficiency, but also PM and NOx - sometimes even in greater quantities than diesels.

Contrary to diesel engines, today, petrol engines do not need SCR (selective catalytic reduction) a.k.a. AdBlue injection in the exhaust system to reduce NOx levels and comply with the Euro 6d-Temp emission standards. The latter to however impose the integration of a particulate filter (OPF). Fortunately, this is simpler to make and to operate than a DPF (diesel particulate filter), as petrol engine exhaust gases are hotter and allow a constant regeneration of the filter.

Pressure on margins

Earlier this month, Arno Antlitz, top finance executive of the Volkswagen Brand, declared that his company faced "heavy financial demands" due to bottlenecks caused by the introduction of WLTP tests. Profits would be at stake even as earnings, sales and deliveries were forecast to hit new records this year, VW executives said.

At Renault’s financial results conference last month, CEO Carlos Ghosn warned for serious impacts from September this year to April 2019. "We have a lot of uncertainties. We don't know how quickly the type approvals will be given. We don't know if customers will be willing to pay the new prices because we need to add technologies," he commented.

Read also: The introduction of the WLTP and the RDE (Real Driving Emission) test are causing a commotion for fleets.

Picture copyright: BMW, 2018