This week the AAA announced the results of its privately-commissioned “real-world” fuel testing – a comprehensive report first started in May 2016 that has only just now reached publication – on 30 car models.
Developed by the European Joint Research Centre and with parallels to PSA (Peugeot Citroen) Group’s own real-world testing that was published in late 2016 and early 2017, the AAA test was modified to suit Australian roads, traffic controls and topography.
The testing, carried out by Melbourne-based engineering consultancy ABMARC, did not surprise many people when it found that the discrepancy between official OEM fuel consumption and that recorded by its own tests averaged 23 per cent higher and that the most recent vehicles – which have to meet more stringent Euro 6 emission rules – had the greatest variance.
The testing was the first major operation in Australia to examine the difference between OEM fuel consumption claims and those experienced by owners.
It follows a similar program by PSA in France in 2016 and 2017 that was triggered by Volkswagen’s diesel scandal and the belief by customers and regulators that car-makers were not disclosing true fuel consumption data.
PSA, which said at the time that it was the first car-maker to test and then list real-world fuel-consumption figures, found the figures were comparable with those reported by customers who were involved in independent surveys and the website logbook.
The results were significantly at variance with its laboratory-based results.
The 60 models tested by PSA – from Peugeot, Citroen and DS – were found to have an average discrepancy between the original laboratory fuel figure and the real-world experience of 2.5 litres per 100 kilometres for the petrol cars, and 2.4 L/100km for the diesel models.
In its report to the AAA, ‘The Real World Driving Emissions Tests’, ABMARC this week said it conducted its Australian tests with different cars on the same route, in similar traffic conditions, in similar weather patterns and with similar driver behaviour.
It said there could be a variance in future tests of the same vehicle of up to three per cent.
Now the AAA wants local testing on all new cars to show consumers a more accurate fuel-use figure based on real-world driving conditions.
“An Australian real-world test program would allow consumers to make more informed purchasing decisions, and allow policy makers to ensure that regulatory settings reflect real-world conditions,” the AAA said in a statement.
“The AAA argues that there is no point in introducing tougher vehicle emissions standards in a laboratory setting unless information on real-world performance is in the hands of consumers.
“For less than $3 per new vehicle sold in Australia, within two years, Australian consumers could have access to real-world testing information for 60 per cent of new cars available on the Australian market.
“This is a very low-cost way to empower Australians to make better informed choices that suit their family budget, health, and their concern for the environment.”
Yet such an animal exists in Europe and, as testing expands after starting last month, it could be this test that would make Australian-based testing irrelevant.
The Worldwide harmonised Light vehicles Test Procedures (WLTP) was introduced in Europe last month to incrementally replace the current New European Driving Cycle (NEDC) tests, introduced in 1970 and updated on two occasions.
NEDC has been criticised by OEMs as being outdated and often misleading, saying the figures from the laboratory tests are unachievable in reality.
In a statement supporting the end of NEDC and the introduction of WLTP, Mercedes-Benz said the change “can be compared to a currency reform”.
“Although the vehicles will not change technically, they will simply be measured by new standards,” the car-maker said.
Automotive data company JATO has researched the change to WLTP and found that fuel economy claims will fall by 13-18 per cent after comparing the new scheme to NEDC on 18 car models.
All new cars being homologated in Europe for launch from February this year must meet the new WLTP rules, with a delayed reporting system meaning all cars on sale by September 1, 2018 must be tested.
WLTP will take over from NEDC in 2020 – the two-year gap because the industry deems it an enormous and complex process.
WLTP testing is still measured in a laboratory but includes higher speeds, longer distances and more dynamic driving, with a greater spread of engine load, gears used and temperatures.
Its second stage has an on-road program called the Real Driving Emissions (RDE) test that, like PSA and ABMARC tests, has monitoring gear strapped to the car taking samples from the car’s exhaust.
ABMARC’s drive route is similar to that of PSA and that coming in force under WLTP.
The Australian test was one-third urban (in Melbourne’s south-east suburbs); one-third rural (Dandenong with points including Harkaway and Ferntree Gully); and one-third Freeway from Melbourne’s CBD to Dandenong. Each segment had a driving minimum of 16km.
The route was 83km and the trip took an average of 105 minutes. ABMARC drove the route twice for hot and cold testing, resulting in a procedure where the drive leg for the 30 vehicles took 105 hours.
By Neil Dowling