There has long been debate about the accuracy of fuel economy and CO2 figures published by car manufacturers. Whilst published figures are technically achievable, in the real world many consumers find them difficult to replicate.  In some cases, a heavy right foot could be to blame, but it is more plausible hat the now outdated NEDC (New European Driving Cycle) testing cycle is the cause. Introduced in the 1980s, NEDC is now unfit for purpose. The replacement test procedure is WLTP (Worldwide Harmonised Light Vehicle Testing Procedure).
WLTP explained
WLTP is regarded as being ‘real world testing’ where cars are put through a cycle of driving that is closer to normal driving situations, such as accelerating, braking and stopping. Additionally, the test uses a variety of different average speeds. That all sounds basic; however, it is a step change from the NEDC theoretical tests. For the first time, testing includes the impact to emissions that options make to cars. It considers how options affect the weight, aerodynamics or rolling resistance, likely to have significant impact on emissions and fuel consumption.
WLTP timeline
Introduced in September 2017 for all new model launches, WLTP will apply to all new cars registered from September 2018. However, as the Government has announced that Vehicle Excise Duty (VED) and company car tax (CCT) will continue to use NEDC figures until 2020, manufacturers will be required to provide both sets of figures, NEDC and WLTP.
Clearly, it is not practical to test under both cycles, therefore a new figure called ‘NEDC Correlated’ will apply, which in effect is the WLTP figure converted back to NEDC. Despite this conversion, reports suggest some NEDC Correlated figures will change significantly.
Who is affected?
The move to WLTP has had significant impact for car manufacturers. The new regime effectively requires costly and time-consuming testing as follows:
all models
all engine configurations for all fuel types
all trim levels
all options including all tyre and wheel combinations.
Brand perception
The new testing procedure will negatively affect some manufacturers, especially for company car sales where CO2 remains the all-important measurement to drive CCT. Action by manufacturers to manage the negativity is likely to include:
the withdrawal from sale of specific engines or engine and option configurations
re-engineering to improve emissions and fuel consumption
simplification of complex ranges
individual options packaged to reduce option complexity.
Impact on residual values
The used car market has proven to be resilient to change over many years. In the short term, Jayson Whittington Chief Editor from Glass’s Information Systems says, “WLTP is not expected to force major changes in demand that undermines residual values (RVs).†However, post 2020 Jayson says, “It is possible that models negatively impacted with the introduction of true WLTP CO2 figures, could fall out of favour with consumers, which would likely impact RVsâ€.
Will the market change?
Nobody really knows what the impact of WLTP will be on the market. The real change is the fiscal impact in 2020 with the adoption of true WLTP CO2 figures. Until then, buying habits are unlikely to change. However, the recent media surrounding car emissions data has not been smooth. A negative stance on significant differences between NEDC test results and WLTP could influence public perception and negatively affect sales rates and therefore RVs.
Jayson says, “At Glass’s we are prepared for any scenario. Our databases are updated and ready to accept manufacturer WLTP and NEDC Correlated figures and the editorial team is constantly watching for signs of any changes in the market to ensure our data remains as accurate as possibleâ€.
