The Worldwide Harmonized Light-Duty Vehicles Test Procedure or WLTP was introduced in September 2017 and represents a new, worldwide standard cycle. WLTP aims to utilise a profile more similar to actual daily driving behaviour than the previous NEDC standard. The new procedure is intended to provide a more realistic representation of a vehicle’s consumption. This is based on a modified test cycle with stricter test specifications.
Both test cycles are carried out in lab conditions. The WLTP test cycle has been redefined in such a way that EU Regulatory bodies view it as more representative of customer driving (ie higher speeds and loads, more dynamic accelerations, fewer and shorter stop phases). The current NEDC test measures curb weight and rolling resistance. WLTP includes the effect of options on the vehicle’s aerodynamics, rolling resistance and mass when measuring its fuel consumption and emissions.
NEDC CO2 and MPG values are obtained when vehicles are Type Approved using the New European Driving Cycle (NEDC) test. In the UK, NEDC values have been used for taxation and registration documentation for many years. This has been the basis for the official CO2 and fuel consumption values for vehicles homologated through the test cycle.
From September 2017 (1 year delay for Light Commercial Vehicles), the old NEDC test will gradually be replaced by the new WLTP test. Due to the change in testing parameters, the CO2 and MPG values obtained under WLTP may be higher than those obtained under NEDC testing.
We currently anticipate that taxation, registration and fleet emission targets may continue to based on NEDC values until 2020/2021. Until that changes, and as there will be a mix of NEDC type approved and WLTP type approved vehicles in the market, consumers need a method facilitating direct comparison between different models and different manufacturers. In line with Government guidance, NEDC figures will therefore continue to be stated, even for WLTP type approved vehicles and, where necessary, these figures will be derived from the WLTP data using an industry standard conversion procedure developed by the European Union, CO2MPAS. These derived values are known by various terms: "NEDC derived", "NEDC equivalent" or "NEDC correlated".
Both the "NEDC derived" and WLTP values will be shown on the Certificate of Conformity, however it is the "NEDC derived " figures that are the values which will be used in registration and taxation documentation and stated in promotional literature, until further notice from the UK authorities.
Please note that fuel consumption and efficiency figures are provided for comparative purposes only and may not reflect ‘real world' driving results. Choice of wheels and other options may also affect fuel consumption and emissions data.
WLTP will measure a vehicle’s individual CO2 emissions, fuel consumption (MPG) and pollutant emissions (for example NOx). This is the case currently under NEDC, however WLTP will take into account vehicle mass (including optional equipment), tyre rolling resistance class and aerodynamics. The values obtained through WLTP will be comparable worldwide.
WLTP will provide customers with greater clarity in relation to the emissions and consumption values of their vehicle. It is important to note that due to the testing aligning closer to real world emissions, this could result in higher consumption and emissions values for vehicles with combustion engines and a shorter electric range for electric vehicles (including plug-in hybrids).
No. At present no changes to the model portfolio are planned. Individual models and their engines will be developed in order to achieve even higher efficiency and reduce emissions as per the regulations. However, models will not be discontinued as a result of WLTP.
As Volkswagen progresses with the WLTP transition, the following type approval timings will apply:
Passenger vehicles (M type and Category N1 (i)):
Light Commercial Vehicles (Categories N1 (ii), N1 (iii) and N2):
NEDC will continue to be used for the official emissions (CO2) and fuel consumption (MPG) values. As and when WLTP figures become available for new model introductions, these will also be available for customers. It is worth noting that the NEDC CO2 values will be used for taxation for the tax years 2017/2018; 2018/2019 and 2019/2020. It is only for new cars registered after April 2020, that the WLTP values will be used for taxation purposes.
Lab tests enable consumers to compare CO2 emissions and fuel consumption across different manufacturers and models in a controlled environment. As a standardised and repeatable procedure, it allows for comparison across brand and model in similar, standardised conditions.
The current lab test, known as the New European Driving Cycle (NEDC), measures fuel consumption (MPG), CO2 and pollutant emissions against EU regulations, in certain, standardised conditions. The standardised testing procedure allows the comparison of emissions between different vehicle models.
We are underway with testing vehicles under the WLTP testing procedure for new to market vehicles. Once a vehicle has been tested under WLTP and the type approval has been issued, customers will be informed of the WLTP values for that vehicle.
© ŠKODA AUTO a.s. 2018