The Volkswagen scandal has heightened concerns about the vehicle emissions testing regime. Farah Alkhalisi reports
Volkswagen’s admission in September 2015 that it had used a software algorithm known as a “defeat device” to artificially lower nitrous oxide emissions from diesel vehicles during testing made headline news. The Volkswagen Group has subsequently had an executive reshuffle, reported financial losses, suffered share price falls, instigated a large-scale recall, and had its credit rating cut. “Dieselgate” has since diversified: poorer-than-certified CO2 emissions are now being investigated in a wider enquiry involving petrol engines and other manufacturers too.
Accusations were quickly made. Bob Lutz, former General Motors vice-chair and product czar, wrote a column for Road and Track magazine in which he blamed the management culture at VW for the diesel-emissions scandal. He described “a reign of terror and a culture where performance was driven by fear and intimidation”. Lutz argued that, whether or not senior managers at the German motor manufacturer knew of the rogue software, Volkswagen engineers were under extreme pressure to lower emissions – at any cost.
Fault lines
Whether fault lies with the company culture or a few rogue engineers undoubtedly Volkswagen, like many of its rivals, has found cutting emissions a challenge.
However, Transport & Environment (T&E), a Brussels-based think-tank and lobby group, has long campaigned for reforms in the emissions testing regime (see panel, below). Clean vehicles manager Greg Archer points to imperative benchmarks from legislative and marketing perspectives – meeting criteria for particular tax bands, for example. “Manufacturers are regulated on this basis, and what they are therefore doing is exploiting loopholes in the test methodology to produce the lowest possible results,” he says. The NEDC – new European driving cycle – tests were last updated in 1997 and are, says Archer, “not fit for purpose and the procedures open to exploitation.”
Designing for test
Yet manipulating poorly regulated testing frameworks is only part of the story: concerns are growing about legal technologies that perform far better under the artificial conditions of a laboratory test than in real-life driving.
Besides rendering official claims for CO2 emissions (and fuel economy) misleading, these can bias the market towards particular innovations. Stop-start – automatic engine cut-out when idling – is one. “Technologies like stop-start perform really well on the NEDC cycle because, during that test procedure, the car is stationary for 20% of the time,” says Archer. “In most driving, you don’t have the vehicle stationary for as long, so you get much less benefit.”
He also singles out turbocharged direct-injection petrol engines, often fitted in a downsizing strategy, which, he says, again “show quite wide variations between test and real-world performance”. London-based Emissions Analytics, which has put some 1,000 vehicles through its own PEMS (portable emissions measurement system) on-road testing in Europe and the US, backs up T&E’s thinking. “There are quite a few technologies that don’t deliver much real-world improvement, but do deliver a much higher NEDC figure,” says Nick Molden, founder and chief executive.
He agrees with Archer on stop-start and notes that, for turbocharged engines on the NEDC cycle, “the turbocharger’s not on for most of the test, whereas in real driving it’s on for a lot of the time”. Molden points out that the starkest differences are typically by engine size. “There’s a clear relationship: the smaller the engine, the bigger the variance,” he says, pointing to the case of sub-one litre engines that have to work so hard in everyday driving.
Some diesel models specifically marketed for their low emissions and fuel consumption have also consistently performed poorly in independent testing. In 2014, German motoring organisation and testing body ADAC shamed the Peugeot 208 e-HDI diesel (automatic) and Volvo V40 D2 1.6 in a survey for the UK’s Consumers’ Association. And testing last year by Italian body Altroconsumo found a Volkswagen Golf 1.6 TDI emitted some 50% more CO2 and burned some 50% more fuel than its NEDC figures suggested.
NEDC-defined nitrous oxide (NOx) levels are routinely exceeded too. The Norwegian Transport Ministry (TØI) and Finland’s VTT found that, although particulates were well contained, the Euro 6-compliant diesel passenger cars it tested showed between four and 20 times the current standard’s NOx limit in city traffic and during cold weather. Emissions Analytics has also found NOx to be on average four times higher than certified from diesel vehicles it has tested.
Reforming the regime
The NEDC is due to be replaced in 2017 by the harmonised world light duty test cycle and procedures (WLTP or WLTC). Nonetheless, this may still not give an accurate picture.
Archer says: “It has higher speeds during the test, it has a more dynamic driving pattern, but it probably won’t produce results as representative as are currently being produced in the US.” He notes that prototype rather than production vehicles will be tested without equipment such as heaters or air-conditioning activated. “From our point of view you need to make sure vehicles are tested as they will be used on the road, and that includes switching on some of these auxiliary and other systems. So WLTP is a step forward, but it’s not going to address all the problems in its own right.”
Molden agrees: “The drive cycle is better than the NEDC, but it still falls short of what I would call real-world driving. The devil will be in the detail of the protocol, how air-conditioning and cold start and the like will be treated. If the protocol is too weak and there are too many grey areas, we could find the gap is not closing by very much.”
A report, published in September for the Committee on Climate Change by Element Energy and the ICCT (International Council on Clean Transportation), echoed this. It concluded that the gap between test and real-life results could widen further as manufacturers found new ways to “optimise” their vehicles.
However, in tandem with a further measure, WLTP could prove more powerful: the proposed RDE (real driving emissions) tests, on-road analyses using PEMS, are intended to tackle NOx. The ICCT sees RDE as “fully justified and much needed”, but a real challenge. NOx emissions from the Volvo, Hyundai and Renault diesel models it analysed early in 2015 were found to be particularly poor and highly unlikely to meet RDE standards. Lobbying from the auto industry has pushed back the date for RDE compliance to 2019, and details of the protocols have yet to be finalised.
Recommendations have been made, however. “What we need is to have a European type approval authority so that the tests are carried out in a truly independent way, and the manufacturers are not paying those who are undertaking the tests for them,” says Archer. Similar calls have been made by bodies including the IIGCC (Institutional Investors Group on Climate Change), which states: “Either strengthen requirements for national type approval authorities to conduct mandatory real driving emissions test procedures for non-CO2 pollutants, including random on-the-road testing, or establish an independent European type approval authority.” It adds that CO2 standards should be set “at an ambitious level that is fully in line with the EU’s 2030 and 2050 climate-energy objectives” in order to trigger a “step-change in innovation across vehicle classes”.
Diesel disincentives
Although the planned reforms to testing have been welcomed, it will be a long time before the impact of WLTP and RDE can be accurately assessed. In the meantime, nitrous oxides remain dangerous pollutants linked to air quality and health issues while vehicle CO2 output is not only continuing to add to greenhouse gases but is making emissions targets on organisational, national and international levels less achievable.
Fleet managers need to make decisions on vehicle procurement while taking into account financial matters. The current UK taxation system – based on official CO2 outputs – favours diesel vehicles, but could be revised in future in light of Dieselgate, and changes in policy could bring a parallel rise in duty on diesel fuel. Volkswagen has also recently warned owners and operators that CO2 figures for vehicles under investigation are now only “provisional”. Despite the admission, HMRC has said it has no plans to reclassify affected car so they are placed in less advantageous tax bandings. Nonetheless, further disincentives include the prospect of banning diesels in city centres – being considered in London, Leeds, Birmingham, Southampton, Derby and Nottingham for 2020 – or higher-cost parking permits, as have been introduced in the London borough of Islington. Some used car market analysts are already predicting a fall in residual (resale) values of diesel cars in general, but especially for VW Group models.
Gerry Keaney, chief executive of the British Vehicle Rental and Leasing Association (BVRLA), advises: “It is too early to report on any long-term implications of the VW crisis. What we can say is that, while 75% of the BVRLA member fleet runs on diesel, we expect its gradual decline in market share to gather pace. This trend pre-dates the VW emissions crisis, as fleet managers started to favour a new generation of small, turbocharged petrol engines. “Furthermore, electric vehicles are becoming more attractive thanks to greater awareness of their lower running costs. Diesel will remain a vital part of the fleet mix for some time yet, however. It is still the most energy-efficient fuel type and often the most appropriate powertrain for long-distance journeys or non-urban freight transportation.”
Dieselgate may not, after all, prove to be disruptive. However, it does highlight that there is no cause for complacency on emissions under current or upcoming legislative regimes. And it could support arguments for taking a more radical organisational approach, whether switching to EVs, using on-demand, shared or car club vehicles to reduce unnecessary mileage, or introducing mobility management schemes and incentivising active travel instead.
Volkswagen scandal: the story so far
On 11 September 2015, the Volkswagen Group was proud to be named the world’s most sustainable carmaker in the Dow Jones Sustainability Indices. It was hailed as an industry leader in terms of environmental reporting and achieved top marks for its codes of conduct, compliance and anti-corruption.
Days later, the US Environmental Protection Agency (EPA) and the California Air Resources Board (CARB) announced an investigation prompted by a study in 2014 at West Virginia University. Sponsored by the ICCT (International Council on Clean Transportation), researchers found discrepancies in NOx emissions of up to 35 times the required US standard in tests of a Volkswagen Jetta and Passat.
Volkswagen issued a public apology at the end of September, admitting that “a particular software” in its four-cylinder Type EA189 engines, built between 2009 and 2015 and fitted in some 11 million vehicles worldwide, had caused “a noticeable deviation between bench test results and actual road use”. Volkswagen Group chief executive Martin Winterkorn resigned, and a recall of cars with the EA189, including those sold by its Audi, Škoda and SEAT brands, was announced – around 8.5 million vehicles in Europe. Class action lawsuits were launched in the US against VW as well as Bosch, supplier of Volkswagen’s software, claiming that the world’s largest auto supplier had “aided and abetted” VW to cheat tests.
In early November, the EPA and CARB announced their finding of defeat device use in Volkswagen’s 3.0-litre V6 diesel engine, and fitted in Audi and Porsche models too. EU authorities confirmed this. Volkswagen initially admitted “irregularities in CO2 levels”. However, after further testing, the company issued a statement on 9 December: “The suspicion that the fuel consumption figures of current production vehicles had been unlawfully changed was not confirmed. During internal remeasurements slight deviations were found. The deviations found in the figures for only nine model variants amount to a few grammes of CO2 on average.”
On 10 December, VW chair Hans Dieter Poetsch blamed the scandal on a chain of errors and said the automotive firm had agreed steps to improve oversight of engine software development to avoid future emissions test manipulations. “We are talking here not about a one-off mistake but a chain of errors,” he said. “Based on what we know today, it was a very limited group which acted irresponsibly.”
The European parliament announced on 16 December the launch of an inquiry into the scandal. MEPs will look into the failure by the European commission and national authorities to prevent the use of defeat devices to cheat emissions tests.
Since the EPA and CARB revelations in September, Germany’s vehicle regulatory body, the Kraftfahrt-Bundesamt (KBA) has tested more than 50 diesel cars from brands including BMW, Mini, Mercedes-Benz, Volvo, Ford, Land Rover, Fiat, Honda, Hyundai, Peugeot, Nissan, Renault and Toyota, as well as VW. Tests by German environmental lobby group Deutsche Umwelthilfe (DUH) on the Renault Espace and Opel Zafira 1.6 litre diesel models have also found excessive NOx emissions (25 times the Euro 6 limit in the case of the Espace), though both manufacturers dispute the results.
Legislative loopholes
Transport & Environment (T&E) first highlighted the gap between real-life vehicle emissions and official test results in 1998, and its subsequent reports have identified ways in which the test regime and its procedures could be manipulated.
“There are about 20 loopholes that we’ve identified and published,” says Greg Archer, T&E’s clean vehicles manager. These include taping over cracks in doors and grilles to reduce aerodynamic drag; fitting lower rolling-resistance tyres or overinflating tyres; adjusting wheel alignment and brakes; using special lubricants; disconnecting alternators to prevent energy use for battery-charging; and testing at altitude, at high temperatures or on super-slick tracks. Auxiliary equipment fitted to vehicles, such as satellite navigation systems and heated seats, is not switched on during testing either.
Most notably, however, T&E has long described so-called “cycle-beating”. This is an additional tactic to optimise the engine management system, and can involve activating selective catalytic reduction (to reduce NOx emissions) or the artificial lowering of CO2 during selected parts of the engine map. Engine software can predict and detect when testing (on a rolling road) is being carried out.
T&E’s annual Mind the gap report uses ICCT-compiled data from eight sources in Germany, the UK, the Netherlands and Switzerland, including user-reported databases such as the German Spritmonitor survey. Mind the gap 2015 identified an average “gap” of 40% between test and real-world CO2 emissions (compared with 8% in 2001).
Vehicles from Mercedes-Benz showed the widest variance – more than 50% for the A-Class, C-Class and E-Class tested vehicles. The BMW 5-Series, Peugeot 308, Renault Megane and Volkswagen Golf diverged from their official outputs by more than 40%. T&E concludes that the system of testing fuel economy and CO2 emissions is “utterly discredited” and that, although “such gaps do not prove the use of ‘defeat devices’ by any manufacturer … they do make it imperative to extend the scope of investigations into the use of this illegal technology to cover CO2 tests”.
A new approach
PSA Peugeot Citroën and the Brussels-based think-tank and lobby group Transport & Environment have agreed to work together to measure and publicise real-world fuel economy figures by this spring. By spring next year, this will cover other pollutants, including nitrous oxides (NOx) for Euro 6.2 passenger vehicles. The procedure will measure real-world fuel economy for each of PSA’s main passenger vehicle models with tests on open, public roads near Paris in real travelling conditions, including urban, extra-urban and motorway driving.
The French automotive company says the procedure will be included in its quality processes, with the results of tests audited and validated by an internationally recognised independent third party, possibly Bureau Veritas.
Jos Dings, director at T&E, says: “Real-world measurements of CO2 emissions and fuel economy will help drivers choose the most efficient models, benefiting consumers, public health and the environment. We are confident that the work we plan to undertake with PSA can generate transparent, robust results that everyone can rely on.”
