Audi and VW SUVs come out best in real-world emissions test

Good news at last for the German car giant – according to the latest results of real-world emissions testing by independent testers EQUA, it’s the Volkswagen Group cars that are now doing the best on nitrogen oxide emissions (NOx).

Specifically, it's the Audi Q2, Porsche Panamera and VW Tiguan which have come in for the highest praise from EQUA. According to its latest tests, the Q2 and Tiguan fitted with the 2.0-litre TDI diesel engine and four-wheel drive, and the Porsche Panamera 4.0-litre V8 diesel 4wd fall into the best A-grade for emissions. That means that in on-road testing, all three cars managed to meet the Euro6 emissions regulations limits which stipulate no more than 0.08g/km of nitrogen oxide (NOx).

Somewhat surprisingly, EQUA’s testing seemed to show that the all-wheel drive variants were better than their two-wheel drive brethren. Of the cars tested, 48 per cent of the four-wheel drive models got an A, B or C rating (which means that they emit no more than 0.18g/km of NOx, equivalent to Euro5 emissions regulations) while only 28 per cent of two-wheel drive models tested managed to be in the same brackets.

Of those 4x4 models, 14 per cent were good enough to meet their Euro6 emissions limits in on-road driving, compared to just 10 per cent of the two-wheel drive models. Those are both disappointingly low scores in general, but they are counter-intuitive. Generally, the extra weight and extra friction of a four-wheel drive system drives up fuel consumption, and therefore emissions.

Nick Molden, chief executive and founder of Emissions Analytics which conducts the EQUA tests, said: "These latest results are very encouraging, and show that it really is possible for large, four-wheel-drive vehicles to top the tables for low emissions. Cars, like the latest Porsche Panamera, are now among the best – which is a huge achievement when you consider that the comparable model or the previous generation Panamera was rated under the lowest grade. This underlines that, with the proper development work, all cars can cut harmful NOx emissions."

Poor economy rating

It’s not all good news on the emissions front, however. According to environmental pressure group Transport and Environment (T&E), cars have not become more economical in the past four years in spite of extra technology and cuts in vehicle weight. T&E’s latest figures show that the gap between real-world and claimed fuel consumption is a massive 42 per cent on average, which the organisation claims means the average driver spends €550 more on fuel per year than they should. That gap has grown from 28 per cent in 2012 and just 14 per cent in 2007.

Greg Archer, clean vehicles director of T&E, said: "There has been no improvement in the average efficiency of new cars for four years because carmakers manipulate tests to achieve their CO2 targets instead of designing the car to be efficient on the road." Drivers, T&E claims, are being forced to buy more fuel, governments' tax-take is lower and climate targets are undermined. "More than a year after "dieselgate" broke, we urge regulators in Berlin and the European Commission to get to the bottom of this "autogate"."

While German brands performed well in the EQUA tests, according to T&E they are the worst when it comes to overstating fuel economy. The figures show that Mercedes is the worst offender, with a gap of 56 per cent between its real-world and claimed figures for the C-Class and E-Class, while Audi lies in second place with a figure of 49 per cent. Toyota, Peugeot and Volkswagen are all called out for having average figures that are more than 40 per cent worse on the road, while only Fiat comes in for some back-handed praise, with a figure of 35 per cent.