Clean air heroes hidden among Euro 6 villains

Ensuring that it remains difficult to pick the saints from the sinners, the latest additions to the comprehensive EQUA Air Quality (Aq) Index show that Euro 6 vehicles continue to deliver drastically different results when tested in the real world.

Toxic times for diesel

Diesel has had something of a rough time of it over the past 18 months. It started with the Volkswagen ‘Dieselgate’ scandal that broke in September 2015, while more recently there have been concerns over nitrogen oxide (NOx) emissions and air quality in general, especially in city centres.

According to Nick Molden, CEO and founder of Emissions Analytics – a company that tests car emissions in the real world – some meet and can even beat the limits prescribed by the Euro6 emissions regulations, while others, according to Emissions Analytics’ data, emit 20 times the NOx that they should.

Read the full article by James Richardson at Businesscar

Can hybrid electric vehicles beat diesels on mpg?

Hybrids have always had a miles-per-gallon advantage in urban driving but new EQUA Index data shows that they are gaining on diesels in motoway or highway driving and, if current trends persist, hybrid electric vehicles (excluding plug-in hybrid electric vehicles) are set to take the lead in 2017.

The dotted trend lines in the above graph, representing motorway mpg for diesel vehicles and gasoline hybrids tested by Emissions Analytics, are converging. While the downturn in diesel mpg may be due to a change in manufacturers’ focus from fuel economy to NOx emissions, what is more striking is the improvement in gasoline hybrid performance on the motorway as a result of technological advances.

The step change in technology is even more noticeable when European EQUA data is compared to North American EQUA results. The graph below shows gasoline hybrid performance in the US is particularly impressive on our combined cycles. With this level of fuel economy it seems unlikely that diesel vehicles will ever make a significant impact on market share in the US. With the mpg penalty of some NOx aftertreatment systems, perhaps it was to gain a fuel advantage over hybrids that Volkswagen resorted to using a defeat device when bringing their diesel models to the US market.

Another noticeable effect of the different product mix in the US is the level of carbon monoxide emissions. Both regular gasoline cars and gasoline hybrids have much lower CO emissions than their European equivalents, with regular gasolines 30% lower and gasoline hybrids 64% lower. This is despite the fact that the US have a less strict limit, at 2.1g/km, than the EU’s, 1.0g/km limit.

When we last wrote about hybrid vehicles back in October 2014, we concluded they were delivering “good but not best-in-class fuel economy, but [were] typically the cleanest, and if you are a light-footed, congested town driver, they are ideal.” Two years on hybrids, particularly in the US, have really upped their game. They are still a cleaner drive than a diesel and may soon offer better fuel economy wherever you drive them but heavy-footed drivers should still exercise caution.

New testing cycle brings CO2 taxation uncertainty

Industy experts have raised the prospect of fleets paying higher emissions-based tax bills following the introduction of  the Worldwide Harmonized Light Vehicles Test Procedure (WLTP), which will replace the existing New European Driving Cycle (NEDC) test in September 2017 and is expected to inflate official vehicle CO2 figures due to its stricter rules.   

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Business Car, 30 November 2016

Emissions Analytics says average diesel emissions are still significantly reduced

Vehicle testing firm Emissions Analytics says diesels can be clean and govenments are highly unlikely to give up the fuel just yet.

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Fleet News 16 November 2016

Are diesels done for?

As the government loses a second high court ruling brought by ClientEarth, many are now sounding the death knell for diesel cars. Not so fast, says Emissions Analytics, diesels can be clean and govenments are highly unlikely to give up the greenhouse gas advantage of diesel in the short- or medium-term.
Since the introduction of Euro 6 in September 2014, manufacturers have been forced to improve their after-treatment systems to meet the stricter legislated limits for NOx. Exhaust Gas Recirculation, Lean NOx Traps, and Selective Catalytic Reduction technologies have been employed as part of a complex strategy to reduce tailpipe emissions. There have been variable successes, with some achieving the regulated limits even in real-world driving and the worst more than 20 times the legal limit. Overall, average NOx emissions from Euro 6 diesels are down 55% compared to Euro 5s.

Nonetheless, there is still the fact that many new cars do not meet the legislated limits in real-world operation. Our data shows NOx emissions are on average 4.3 times over the limit for Euro 6 cars and, after a period of improvement, this Conformity Factor is rising. This is the heart of the issue, as to whether diesels are the major and unavoidable cause of poor air quality in towns and cities.

Consequently, there have been many suggestions made to combat the problem of dirty diesels. These range from the London Mayor’s T-charge, to a diesel scrappage scheme, to a total ban on diesel vehicles in certain zones. However, Emissions Analytics’ data shows that modern diesels in their own right can be clean.

Since the launch of the EQUA Air Quality Index six months ago, twelve cars have how achieved an A-rating including the latest Volkswagen Tiguan, meaning it has met the 0.08g/km limit in real-world driving.

This proves that diesels can be clean and the reason most are not is down to a failure of regulation and enforcement and not the technical impossibility.

There is also the issue of CO2 emissions to be considered. Despite Donald Trump tweeting that climate change was, “created by and for the Chinese in order to make U.S. manufacturing non-competitive,” the British government has an empirical view on global warming and stands by its commitment to cutting its carbon footprint. Would ministers give away the 16% CO2 advantage – according to Emissions Analytics’ testing – diesel has over gasoline for the same distance driven in real-world operation, until there is a viable alternative.

In the future electric and hybrid vehicles may deliver the CO2 advantage required, as well as greatly reducing, or eliminating, NOx and other harmful emissions, at which point diesel powered engines for passenger cars may come to the end of the road. However, with a share of the market of less than 2%, there is still a way to go for these vehicles. Until then, Emissions Analytics’ data strongly suggests the policy focus should be on sorting the clean from the dirty diesels and incentivising manufacturers to bring forward clean technology.

The latest EQUA Aq Index results are available online

Emissions Analytics’ new EQUA Carbon Dioxide Index reveals car manufacturers miss target by 39%

VW dieselgate: Is it even about the environment

Volkswagen might have agreed to one of the largest ever corporate settlements to tackle the emissions scandal, but industry insiders are now questioning whether that’s enough.

Read more

A visualisation of cars tested for the EQUA Aq Index

A visualisation of cars tested for the EQUA Aq Index, split by Euro standard and fuel type, showing progress towards reduction of NOx emissions.

Emissions Analytics delivers big data to ENTRIS in definitive HGV emissions tests

Snapshot #9: Class matters when it comes to MPG

We looked at our data on over 750 EU cars tested, to see how much of an influence vehicle class was on variance between the NEDC-derived official MPG and our cycle and found:

• Petrol sports cars come closest to their official figures

• The MPG gap is worse for small cars, whatever the fuel

• Overall the gap is almost always bigger for diesel engines.

Motor Trend: The world’s two most efficient internal combustion cars

Real-world testing of hybrids in California read more

CarAdvice: Opel alleged to be secretly fixing cars with illegal NOx emissions

One of Belgium’s national TV networks is claiming that Opel is secretly performing upgrades on some of its diesel-powered vehicles, to reduce harmful emissions. Read more.

Cargo weighs heavily for some LCVs

You may remember back in February we announced we were going to extend our test programme to include light commercial vehicles. Well, testing has been underway for the last few months and we have found that fuel economy and nitrogen oxide (NOx) emissions vary considerably depending on whether or not vehicles are fully laden.  Our sample is currently small, but we wanted to share some early results.

A van used for work is rarely empty so unlike the official tests, our cycle is repeated twice, first empty and then again at 100% payload. We have tested a number of the most popular Euro 5 vans on the road today and the average impact on fuel economy and NOx by manufacturer when driven fully laden can be seen on the graph below.

Across all vans we have tested, NOx levels are 5.9 times the Euro 5 limit of 180 mg/km when tested empty on our real-world route. Fill these vehicles to 100% of their individual payloads and this ‘exceedance factor’ increases to 12.2 times the legislated limit. However, the impact of load varies from vehicle to vehicle. For instance, Volkswagen produces the cleanest van for NOxwhen empty and despite a 225% increase when full, this vehicle is still the cleanest we have seen. The Ford vans, on the other hand, are higher than the Volkswagen unladen (7.1 times the limit) but this barely increases when full (to 7.6 times), leaving them only marginally more emitting than the Volkswagen.

Fuel economy

Like passenger cars, vans deliver a worse fuel economy on the road than during the official NEDC cycle. The average for the vans we have tested is 14% below official MPG figures when tested empty. Fill them up and the average MPG drops to 27% below the NEDC figures. Just like NOx , there is variability between different models. So far, the Renault gets closest of all the vans tested to its official MPG result (2% below), but suffers badly when laden, dropping a further 13%, whereas load has the smallest impact on the Citroen with a 5% penalty.

It is also interesting to note that there is very little variance between urban and extra-urban driving, for example at 50% load.  Typically, unladen, extra-urban MPG would be higher than urban, but the increase in rolling resistance means than on average we found MPG at the higher speeds was 2% lower than in urban driving.

Our programme of van testing is on-going and will grow in 2016.  The data so far shows – potentially even more so than for cars – that it is vital to match the right van to the right usage.  There are very different characteristic performances between the vans tested so far, making the best purchase decision highly dependent on whether it will be used mainly for urban delivery driving, long distance trunking or carrying heaving loads.

CO2 variance from official results by country

Real Driving Emissions – How REAL is it?

With the recent Volkswagen scandal focussing the world’s attention on the air quality problems associated with diesel cars, campaigners for clean air have expressed dismay over the EU’s decision not to impose stricter rules for testing new cars on the road. However, Emissions Analytics data shows that full compliance with the Euro 6 limits on oxides of nitrogen (NOx) is already being achieved by some vehicles, and thinks that the industry is on course to clean up dirty diesels.

What is interesting to note from the graph below is that of the 400+ vehicles tested by Emissions Analytics, only one Euro 5 car met the Euro 5 NOx limit, whereas four Euro 6 vehicles have already met the more challenging 0.08g/km Euro 6 regulation. The spread of NOx levels has also reduced in absolute terms with Euro 6, although proportionately the spread is similar to the Euro 5s before them. It is also abundantly clear that the majority of cars we have tested have failed to meet the regulations in real-world driving, with the average NOx levels four times more than they were certified as emitting.

The introduction of a Real Driving Emissions test (RDE) is set to reduce this divergence between laboratory results and real-world driving. Yet the announcement of the Conformity Factors last week, which set the levels of NOx vehicles are permitted to achieve during RDE, have been criticised by many as being too lenient. Our data shows that 36% of Euro 6 diesels have already met the 0.168g/km implied by the 0.08g/km limit plus the Conformity Factor of 2.1 that will come in from 2017 onwards and apply until 2020/1. However, taking into account the test-to-test variability with portable testing, which the Joint Research Centre of the EU recently estimated at up to 30%, manufacturers will need aim for emissions below the 0.168g/km to avoid being caught out during the RDE test. Using that variability number would suggest manufacturers will need to target 0.129g/km. This means that the 0.08g/km limit will be exceeded by around 60% on average in real-world driving. Of the Euro 6 diesels we have tested, 29% already meet this limit, as well as all gasoline cars.

Finally, all models will not need to comply until September 2019, and therefore we conclude that the new regulations as currently proposed will prove easier to achieve than might have been expected, even though some manufacturers and models have a greater task than others. As ever, we will be monitoring the situation and will report back with an update soon.

How PEMS works

A Portable Emissions Measurement System (PEMS) is used to measure vehicle emissions on the road rather than in the laboratory. This methodology, soon to be included as part of the official test for new cars, is used by Emissions Analytics to build a detailed database of real-world emissions. Data from over 1000 real-world vehicle tests is available via subscription. Contact us for further details

Consumers being mislead on emissions – with or without illegal acts

We set up Emissions Analytics four years ago to understand the differences in emissions and fuel economy between the laboratory test and real-world driving conditions in Europe and the United States.  Over that time, Emissions Analytics has tested over 1000 cars in Europe and the United States, including over 200 European diesel passenger cars, and makes this data commercially available to many parts of the automotive industry to help bring about a better regulatory regime and help rebuild trust between car manufacturers and consumers.

The illegal action of one manufacturer in the United States threw light, in dramatic fashion last week, on a European situation of higher than expected real-world emissions generated wholly or largely through legal activities.  Even legal activity, where it gives rise to misleading results, can be enough to cast wrongful doubt on a whole industry.  Having robust, independent real-world emissions data that can sort good from bad is the future, and we plan to lead this.

To summarise the facts in the European market, we have found that real-world emissions of the regulated nitrogen oxides are four times above the official level, determined in the laboratory.  Real-world emissions of carbon dioxide are almost one-third above that suggested by official figures.  For car buyers, this means that fuel economy on average is one quarter worse than advertised.  This matters, even if no illegal activity is found.  These differences may well be explained by limitations in the official system, rather than through illegality.

Emissions Analytics has been highlighting these issues for some years now, along with many partners who have analysed our results as well as similar data from other sources.  In order to make our findings more accessible and useable to the market, we will be launching an independent accreditation initiative, and we invite all interested parties to participate.

Air quality…it’s hotting up

Will 2015 be recognised as a turning point in the campaign for clean air? It certainly has the potential to as there are a number of threads which, if they come together, could determine the future prospects for urban air quality in Europe.

For instance, the second stage of the Euro 6 regulations for passenger cars will come into force from September. All new cars registered will need to meet reduced limits for NOx, albeit still measured on the artificial laboratory New European Driving Cycle (NEDC).

Also, negotiations will come to a head in the EU around the Conformity Factor for the third stage of the Euro 6 regulations. This will see the use of Portable Emissions Measurement Systems (PEMS) becoming mandatory for the first time. Emissions Analytics has argued long for such portable testing in real-world driving, so this is significant progress. However, a high Conformity Factor (the permissible exceedence of the regulated limits) for a long period could limit the effectiveness of the regulation.

Additionally, the UK government must come up with a new air quality plan after its defeat in the Supreme Court. The activist legal group, ClientEarth, accused the government of failing to meet legal limits for air pollution and the Supreme Court found in its favour, instructing the government to draw up a new plan by the end of 2015.

So, let’s take stock of what Emissions Analytics’ real-world test data is telling us on these points.

The second stage of the Euro 6 regulations is likely to reinforce the existing trend of significantly reducing NOx, but there will still be large exceedances over the regulations. Emissions from Euro 6 diesels are on average 0.340 g/km when they should be 0.08g/km, although this is a 54% reduction on the 0.736 g/km from Euro 5. The issue is much less for gasoline vehicles, which are on average 24% below the 0.06g/km limits. However, 22% of vehicles tested by Emissions Analytics did not meet the limit.

Regarding the Conformity Factor at the third stage of Euro 6, there is growing evidence that, in time, a low factor is viable. Across all Euro 5 diesels we tested, just one met the regulated level.  So far for Euro 6 four have already met the limit, using a mix of selective catalytic reduction (SCR) and lean NOx trap (LNT) after-treatment systems. There is still much work to do, but the evidence shows that the limits themselves could be met.

A new version of the UK’s air quality plan is being written by the Department for Environment, Food and Rural Affairs and Secretary of State Liz Truss has announced consultation “later this year”. Crucial in our view will be the understanding and modelling of primary NO2 emissions, as this is a major contributor towards roadside pollution yet is not specifically regulated by Euro 6. Emissions Analytics has found that the variation in this fraction of NO2 in NOx between models has also grown, as a result of differences in after-treatment technologies; for Euro 6 diesels it is 17%-80%, where previously is was 27%-70% in Euro 5 models.

To assist the industry in making a success of Euro 6, Emissions Analytics recently launched an online database of its results, which will be updated in real-time as it continues its rolling test programme. We don’t know yet how these important developments will impact urban air quality but we will be tracking it closely.

The impact of cold starts on NOx emissions