Emission Analytics on RDE Regulations

A couple of years ago Nick Molden felt that the automotive industry was often operating on the basis of poor real-world data in regards to fuel consumption and emissions. As a result, he decided to found Emissions Analytics, an independent commercial test house to measure exactly this: real-world fuel economy and on-road emissions. At Emissions Analytics, technicians and emissions experts use Portable Emissions Measurement Systems (PEMS) with real drive cycles and dynamic performance analysis with laboratory equivalent accuracy. In the light of current RDE regulation and the recent Volkswagen Diesel scandal, Automotive IQ interviewed Mr. Molden during IQPC’s 3rd RDE Conference in Berlin. Mr. Molden, you started Emissions Analytics because you were unsatisfied with the choice of reliable automotive emissions data?

The inspiration was that I found it was a mark of failure that this large, very important industry was operating on the basis of poor real-world data, which explained why we had bad air quality and why consumers were buying cars and getting fuel efficiency much lower than they thought they were going to get.

Right now a lot is going on within the industry regarding test procedures. We see different test settings, and legislation is being created as we speak. However, you focus on PEMs (Portable Emissions Measurement Systems) only. Up to now you have 1000 test cycles since 2011.

That’s actually 1000 different vehicles, all of which have gone through the same on-road test of about 3 hours in length. That is split 700 in Europe and 300 in the United States.

Based on the data you have, would you say that especially the Euro 6 cars are meeting the real-world requirements?

No, they’re not. Not by a long way. In fact, they’re on average four times over the regulated NOx limit of 80mg. However, the trend is improving, and it’s also very important in the current climate to point out that this is not saying that any of these are acting illegally. It’s exploiting the difference between a very gentle regulatory cycle at the moment and real-world driving, which is more aggressive. Not that our driving is very aggressive: it’s very real-world. That "four times" is due to manufacturers optimizing to the NEDC (New European Driving Cycle) – understandably in a competitive market. This is driving this difference between laboratory and real world, which comes out to four times on average. That’s over 300mg per kilometer for diesel on average.

From 200 tests, only five cars met the emissions target.

That’s right, one Euro 5 and four Euro 6.

That’s actually not that many cars, but you made it sound like it’s a good thing, because it would prove that it’s still possible to meet the requirements.

Absolutely. To the question, "Can diesels be clean," the answer is yes. And actually, interestingly, one of those five is a VW. Given everything that has happened in the US, it shows that in Europe, VW is doing pretty well.

But still, the whole label of clean diesel certainly took a hit from the Volkswagen emissions scandal, particularly in the US, although the diesel market is not that huge there.

That’s the thing. Diesel was trying to make the case that people should switch to it, whereas in Europe, half the people have diesel so it’s different. It will take more for people to switch away from diesel, which they like because of the drivability and good fuel economy.

You don’t agree that the whole emissions scandal could be the final nail in the coffin for diesel technology in the US?

In the US market, probably yes – for passenger cars in the US – but definitely not in Europe. That’s because the US has not got used to the benefits of diesel, and the aversion amongst consumers is going to be too great, whereas in Europe people are used to the benefits of diesel and won’t want to switch away from it. I think it’s very different. In the US you have hybrid penetration of 8% in California, and that delivers equivalent fuel economy to a diesel vehicle and it’s completely clean. So why would an American consumer switch from a gasoline hybrid to a diesel? I just can’t see it happening. And the brand of clean diesel, which the German manufacturers had been investing in, is now badly tainted in the US.

As far as we know and despite the whole ongoing emissions scandal, it’s not a lack of engineering skills at VW which caused all of this. Based on your data and experience, what would be the technological trends that will help reduce the emissions from diesel cars?

What you need to do is look at the United States first. What you have there is BMW and Daimler, both of which are producing legally compliant cars in America on much lower limits than Europe, and they are using SCR systems (Selective Catalytic Reduction), or combinations of SCR and LNT (Lean NOx Trap), complying at 31mg/km. Copy that technology and that deployment to Europe – it’s perfectly possible. The question is how the commercials work. BMW and Daimler in the US are much more premium vehicles, with higher prices than they are over here, so they can lose the extra cost of the after-treatment system more easily in the US market than they can in the European market. The question is if the compromise on vehicle cost, fuel economy, boot space, etc. it does have consequences, but it is perfectly possible to make diesel vehicles comply with the 80mg limit.

Do you feel that this discussion is really taking place within the OEMs? Do you feel that there is a mind shift going on?

Yes. Particularly for small cars where the cost of after-treatment on a city car would be a higher percentage increase, I think that’s where commercial questions will be asked. On big 4x4s or big saloon cars, it’s relatively small beer. Clearly, there are currently the latter stages of the negotiations about the conformity factors and boundary conditions, and I think the concern is that with in-service surveillance coming along within the regulations, plus what we do, no manufacturer wants to get caught out with a car that does not comply. So when they did the test, the car passed, because they drove it in a different way that was still RDE (Real Driving Emissions) compliant, but which could actually have more aggressive driving. They didn’t want to be inadvertently found to be non-compliant at some later date. So, having to engineer that margin of error and to make sure the car does perform cleanly across the whole engine map, is I think the big focus at the moment. No one wants to be the next one caught violating the rules.