Fleet News

New diesels found to be 71% cleaner than petrol models


Emissions Analytics has revealed that the latest Euro 6d-Temp diesel models emit, on average, 71% less particulates that petrol equivalents.

New diesels also emit 18% less CO2 in real-world testing, according to early testing from Emissions Analytics.

The organisation, which complies the EQUA Index for emissions conformity, uses a Portable Emissions Measuring System (PEMS) that tests the actual tailpipe emissions on the road.

When looking at Nitrogen Oxide (NOx) specifically, Emissions Analytics found average emissions were 48mg/km, meaning the cleanest diesels are getting close to the average NOx emissions from new petrol vehicles, which is 36mg/km.

Even before RDE, Emissions Analytics found that at least 30 diesel models achieved real-world emissions of 80mg/km or less.

The lowest NOx emission recorded so far this year is the 2017 model year Mercedes CLS, with selective catalytic reduction after-treatment and type-approved for 6d-temp, which recorded 15mg of NOx per km.

In May 2013 the cleanest 10% of diesels tested emitted 265mg/km of NOx and the dirtiest 10% emitted 1777 mg/km – a ratio of 7 to 1.  In 2017, the cleanest 10% achieved 32mg/km, but the dirtiest 10% were still emitting 1020mg/km, a ratio of 32 to 1.

Emissions Analytics says that in around 10 years the majority of diesels on the road are likely to be of the cleaner variety and that the current figures suggest a switch to petrol vehicles may not deliver the desired long-term air quality improvements.

It warns policy makers to be careful not to chase the past, but rather understand the models – with their emissions and fuel economy characteristics – that are already coming through, whether they be diesel, gasoline, hybrid or electric.

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  • Ian Clarke - 03/07/2018 14:50

    When will people wake up to the fact that it isn't so much the emissions from new diesels as is with the vehicles that have put a few miles on the clock, Particulate filters...! has anyone seen the muck that comes out of them when they are being manually regenerated or cleaned, is this still not pollution...? I have been a diesel fuel injection engineer for over 40 years and still working. I am amazed at the total rubbish that manufacturers of diesel engines try to bamboozle the people of this planet.

    • Carl - 03/07/2018 16:52

      During the regeneration process the harmful particulates are turned to ash and collected in the particulate filter. If smoke is coming out it isn't working properly. Have you tested a petrol vehicles emissions with 'a few miles on the clock'? Parts deterioration is the same execpt diesel components can be repaired, petrol ones can't.

  • M Bertoncini - 07/07/2018 14:18

    what will happen to Trucks and bus that run on Diesel fuel .A truck and bus emit more exhaust than a car At the moment EV do not have the range to make them viable for everybody unless you afford a Tesla.not every home is suitible to install a charging point and the £400 pound to install the unit..at the moment you have the choice to buy the battery or lease at £49/month for 4500 mile /year at todays pump prices a Diesel can run for 335 miles in most cases that is the average miles per month ,ok on electric thats £5.50 ,plus the £49 lease makes it £54.5 per month or 465 miles or 5580 mile, at that miles the battery lease increases.On a lighter note how many Goverment cars are EV's?

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