3rd April 2018

How is the new WLTP emissions test already having an impact on fleets?

Over the last few decades, it’s fair to say that very few private and at-work motorists will have seen their vehicles achieve or exceed the ‘MPG’ figures cited in manufacturers’ marketing and other material.

Why this traditional disparity between published and real-world MPG and CO2 figures?

Putting individuals’ driving styles to one side, a significant reason behind the sometimes relatively abysmal economy figures experienced in the real world is that vehicles have until now been assessed using the New European Driving Cycle (NEDC) test devised in the eighties1. Conducted in a laboratory and based on a theoretical driving profile that many voices have described as unrealistic, the NEDC test took roughly 20 minutes, covered 6.8 miles at an average speed of 21mph and a maximum of 75mph, incorporated fixed gear-shift points and didn’t take into account modern systems like climate control.

How the new test changes things

The new WLTP test (which stands for ‘Worldwide Harmonised Light-vehicles Test Procedure’) will last for 30 minutes over a distance of 14.4 miles, acknowledge vehicles’ varying gear numbers and shift points to account for the new breed of 9-speed gearboxes for example, will see the maximum speed increased to 81.3mph and is conducted at lower temperatures.

Another new test is also being introduced across Europe called the Real Driving Emissions (RDE) test, undertaken on actual roads during every day driving conditions, with monitoring equipment attached to vehicles’ exhausts.

Taxation implications and the timings surrounding WLTP

Addressing how WLTP will affect car tax, the first year of which is based on CO2 emissions, the DfT somewhat reassured fleets by explaining that when the new system is used to calculate vehicle tax, only unregistered vehicles will be affected. In the meantime, cars approved under WLTP will see their figures crunched by an algorithm that will convert them into NEDC-friendly numbers to maintain some consistency for the time being2.

WLTP will be rolled out in a staggered manner, with models scheduled for sale by September 2018 now being submitted. ‘Step 1’ of the on-road RDE component won’t be mandatory until September 2019, though, and manufacturers, government, car leasing firms and others are expected to still rely on current NEDC figures until April 2020, taking some of the pressure off organisations’ finance departments3.

WLTP’s influence already being felt

Despite WLTP not taking a real hold for a couple of years here in the UK, fleet managers, SME owners and indeed private car buyers and leasing customers can’t stick their heads in the sand, though – and the new tests are already having an impact.

“BMW slashes model range amid WLTP fears”, read a recent BusinessCar headline4 following the divulgence from a senior leasing sector figure that BMW had notified them that the production of a ‘huge’ list of their models will be halted by around July 2018. We have had this news verified by one of our own contract hire sources, too.

Plug-in hybrids especially temporarily impacted

At a time when the government, manufacturers, environmental bodies and other organisations are avidly promoting green hybrid and electric vehicle adoption, all plug-in hybrid BMWs except the 5 Series will temporarily stop being produced and offered to business and personal contract hire customers, along with the unsurprisingly popular 520d EfficientDynamics and certain variants of X1, X5 and X6 SUVs.

BMW describes its decision as a proactive step with the aim of aligning its range with new global regulations, and it must be stressed that production of certain models will merely be paused with the intent of recommencement as soon as the marque feels its proverbial ducks are in a row again.

Leasing companies are also reporting that plug-in hybrid models from other brands, such as the Mercedes C-Class, are also proving difficult to order for customers, the view understandably being formed that manufacturers are likely tweaking their products in light of WLTP’s arrival.

Motoring website Honest John5 has long campaigned for realistic fuel economy figures and its RealMPG database now boasts almost 144,000 submissions from real motorists. The publication quite rightly reminds its readers that plug-in hybrid and range extender models have typically been known to fall well short of their official MPG figures in the real world. Figures of around 150mpg are customarily banded around, translating to somewhere between 40 and 70mpg in reality because their users don’t have the appetite and discipline to leave them on charge every single night.

Manufacturers are busy re-homologating their MPG, CO2 and NOx figures and Toyota, for instance, has predictably increased all such figures across its various Prius models, the 12g/km increase for cars with 17” alloys now precluding them from London Congestion Charge exemption6.

Manufacturers’ results from the first wave of WLTP and RDE testing

Greenpeace’s Unearthed7 journalism project has investigated how car manufacturers have been performing in the first wave of realistic emissions tests. BMW’s models have come out extremely positively with, for example, all bar one finishing below even the current Euro 6 laboratory limit of 80mg/km NOx not to mention Euro 6d-TEMP standards that temporarily permit up to 168mg/km NOx. Various new Citroen models, the new Ford Fiesta, several Vauxhall models and the Renault Megane Energy dCi 160 EDC didn’t fare as well according to Unearthed, however, the latter emitting almost five times the levels of NOx permitted. Mercedes’ results were very promising, though, while the general observation was that models fitted with selective catalytic reduction (SCR), a NOx trap, diesel oxidation catalyst (DOC) and/or particulate matter filtering technology performed well in terms of meeting or bettering forthcoming Euro 6d standards, which it must be remembered aren’t yet mandatory anyway.

Summing up

In the here and now, then, it seems that the primary initial impact of the new WLTP and RDE tests on fleets and other motorists is in the form of delayed or in some cases cancelled orders of plug-in hybrid models, or such cars being temporarily dropped from certain manufacturers’ ranges.

Moving forwards, though, with OEMs busy re-homologating their line-ups and updating their CO2, NOx and MPG figures, it’s undoubted that at-work and private drivers will eventually see the emissions-related road tax values and BIK levels increase on many models in a couple of years’ time.

The way in which the new tests will make viable fuel economy figures more realistic is nothing but positive, though, helping to reduce the level of disappointment that many motorists have and continue to experience. Ultimately, the EU has set carmakers a ceiling of 95g/km CO2 to meet by 2020/21 and the WLTP-RDE duo will play a key role in achieving this, benefiting almost everyone on the planet as a result.


1. http://wltpfacts.eu/what-is-wltp-how-will-it-work/
2. http://www.dft.gov.uk/vca/fcb/wltp.asp
3. https://www.carmagazine.co.uk/car-news/tech/what-is-wltp-worldwide-harmonised-light-vehicle-test-procedure-explained/
4. http://www.businesscar.co.uk/analysis/2018/bmw-slashes-model-range-amid-wltp-fears
5. https://www.honestjohn.co.uk/news/buying-and-selling/2018-03/bmw-cuts-model-range-as-new-wltp-test-looms/
6. https://fleetworld.co.uk/toyota-re-test-figures-highlight-issues-with-wltp-tax-delays/
7. https://unearthed.greenpeace.org/2018/03/02/depth-carmakers-performed-first-wave-real-world-tests/