12th September 2017

Forecasting realistic fuel consumption and spend should now be more achievable for fleets and motorists following the introduction of new European tests

Attempting to achieve an average combined miles per gallon or ‘MPG’ figure closely resembling the one published by a car’s manufacturer has historically felt like a tall order that actually seems impossible for certain makes and models. With economy an important influencing factor for many motorists these days, plenty are left irked by the seemingly unfathomable discrepancy between fuel consumption figures quoted in marketing material and the real-life performance of a wide range of cars.

Why the difference?

Voices from or specialising in the automotive industry have typically pointed to the unrealistic way in which cars are tested as the culprit, the official New European Driving Cycle (NEDC)1  test that was introduced in 1970 essentially taking place in laboratory conditions that don’t reflect real life out there on the open road.

VDA, which is basically Germany’s equivalent of the SMMT, calls the NEDC test ‘obsolete’, stating that the city driving element is overly long with too few acceleration events, the speed parameters are considerably disproportionate, topography doesn’t feature in the equation, and commonly-used functions such as air conditioning, infotainment and heated seats aren’t considered.

All the chatter these days surrounds Euro 6 emissions standards, with Euro 1 having debuted back in 1992 under the ‘Euro-norm’ banner. According to VDA, CO2 reduction technologies developed over recent years such as start-stop have a disingenuously strong effect on the test bench compared to on the road, by as much as 10 per cent.

UK media publications such as The Telegraph have regularly commentated on motorists’ frustrations, describing the reasonable-enough-sounding theory behind NEDC tests as flawed because they cover woefully short distances, don’t take temperature changes and weather conditions such as headwinds into consideration, and acceleration to 31mph is set to 26 seconds – a far cry from real life.

Has anything been done to address the issue?

A number of initiatives have been made over the years to try to enable motorists to obtain a more accurate picture of various cars’ real-world fuel consumption figures, a prime example being Real MPG from Honest John3. In 2013, two years after the platform’s launch, it cited that UK drivers were losing £4.45 billion in fuel due to overstated official mpg figures. Tens of thousands of motorists from around the UK have inputted their fuel economy findings into the Real MPG website, often based on detailed spreadsheet calculations reflecting actual forecourt visits compared against mileage records plus tank and fuel consumption observations.

Honest John Real MPG

In June 2016, Emissions Analytics4 launched a rating scheme called the EQUA Index with the aim of providing private and fleet motorists along with operators of buses and other large vehicles with transparency surrounding true outputs of polluting nitrogen oxide (NOx) emissions by using their own portable emissions measurement systems (PEMS).

Nitrogen oxide emissions came to the fore in recent times when various manufacturers were found to have published questionable figures, and the link to public health and complaints such as asthma has placed just as much importance on reducing NOx levels as those of CO2.

The first round of EQUA Index results proved eye-opening with several well-regarded cars boasting Euro 6 compliant engines surprisingly ending up in the dirtiest ‘H’ bracket5. Data from this particular transparent emissions platform actually started pointing to Euro 6 petrol engines as being cleaner than their supposedly more desirable diesel counterparts, giving fleet managers and motorists an added decision to make.

Things look decidedly rosier from this month onwards

Some positive moves have just been made, though. Although implications further down the road of Brexit are unknown, the arrival of September brought with it some welcome news for motorists, which is of particular benefit to fleet managers and the drivers under their care. Environmental and financial constraints and goals increasingly govern the choice of vehicles offered to company car drivers and it’s fair to say that the sometimes significant difference between published and achieved fuel consumption has given some fleet managers a headache when they come to analyse vehicle performance and fuel spend.

Two new tests were introduced on September 1st to replace the NEDC. The first is called the Worldwide Harmonised Light Vehicles Test Procedure (WLTP for short) and, like its forerunner, is conducted in a laboratory. This isn’t cause for dismay, though, because such tests are identically repeatable in a controlled environment, ensuring that all vehicles are subjected to the exact same parameters. The WLTP also promises to resemble real life driving conditions more closely with faster speeds, sharper acceleration and more abrupt braking, and testers will fit cars with an abundance of likely optional equipment in order to present potential drivers with a better indication of worst-case figures.

The European automotive industry commendably appreciates that consumers and indeed businesses have become increasingly sceptical and wary, so the second new test to run in parallel to the WLTP is called Real Driving Emissions (RDE), bringing that previously missing element of credibility to the emissions-testing party. RDE tests will be undertaken using portable equipment fitted to vehicles and the routes driven will encompass a set range of variables no matter where they are carried out in the world.

French titan Groupe PSA has also just announced the development of its own real-world fuel consumption test protocol in partnership with T&E, FNE and Bureau Veritas. They’ve overseen the analysis of 60 vehicles in 430 different tests over eighteen months, culminating in the publication of a detailed and candid report containing the findings. With a margin for error of just 3%, PSA is confident that its own test protocol is robustly reproducible, and its internal data will continuously be compared alongside figures submitted by PSA customers as well as fuel economy information sent to public websites like Spirit Monitor in Germany. PSA’s efforts have identified an average difference of 1.74 litres per kilometre between their test results and NEDC figures.

When will the new tests’ figures be noticed?

All cars registered from September 2019 onwards will come with RDE figures, but this measure has already started to be applied to new models at the Type Approval stage. Meanwhile, WLTP data will also be provided as default for car types approved from this month onwards, but most existing models will cite figures based on the old NEDC regime, meaning there could be some crossover and confusion for a while.

Eventually, once older models are phased out and the processes settle down, Trak Global Group is optimistic that these two new tests will make it easier for fleets managers to more accurately identify vehicles that meet their criteria in terms of emissions and also fuel economy.

Driver behaviour

As a leading telematics solutions pioneer, we see first-hand how driver behaviour also plays a significant role in achieving fuel consumption figures as close as possible to those published by cars’ manufacturers. Reminding company car drivers that driving smoothly boosts not only safety but also efficiency is a worthwhile addition to organisations’ training endeavours or fleet handbooks. Refraining from driving erratically will also keep vehicles in better condition, reducing servicing and maintenance costs as a result.

Thinking back to the whopping sum of money quoted by Honest John as being lost by motorists in relation to overstated mpg figures, this should almost certainly become a diminishing issue for fleet managers over coming months and years thanks to the new tests and other endeavours.