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The "Worldwide harmonized Light vehicles Test Procedure" (WLTP)

How you can navigate the road from NEDC to WLTP

The countdown is on and as of September 1st, 2018, the new “Worldwide Harmonised Light Vehicle Test Procedure” or WLTP will become mandatory for all new vehicles. Here’s everything you need to know about what this means for you and how Alphabet can help.

What is WLTP?

The WLTP is the new laboratory test for measuring fuel consumption and emissions. As its name suggests, the aim of the WLTP is to harmonise test procedures around the world to create an equal playing field. This new test procedure has been developed by the United Nations Economic Commission for Europe (UNECE) together with Europe’s automotive industry and will replace the “New European Driving Cycle” (NEDC) lab test, which has been in use since the 1990s.

The road from NEDC to WLTP

The NEDC or New European Driving Cycle was designed to replicate how each car was used in Europe. However, since it was designed in the 1980s, adopted in 1990, and last updated in 1997, it does not account for modern changes in car usage and technology, which is where the WLTP comes in. 

The NEDC was initially developed for petrol cars only, but it quickly became a tool used for estimating the power consumption of diesel cars, hybrids and all-electric cars, too. This test relies on four urban driving cycles of 20 minutes and one driving cycle outside the city. However, it does not take into account real driving conditions or the influence of optional equipment on a car, which means that the NEDC’s fuel consumption ratings are close to impossible to achieve on the road.

What’s changing?

Although the WLTP tests also take place in a lab, this new procedure uses more realistic driving data, which have been collected from all around the world. It also comprises four cycles, but these are now 30 minutes long instead of 20, and each has its own imposed average speed - rated low, medium, high and extra high. The WLTP also looks at a number of driving situations, such as stopping, braking or accelerating, and considers the influence of any extra features which are added to the car. With these changes and many others coming into effect, the WLTP seeks to better align laboratory test results with the actual day-to-day use of vehicles, while at the same time taking today’s engine technology into account.

Along with the introduction of the WLTP, the EU Commission will enforce Real Driving Emissions (RDE) tests, which will come into effect from September 2019. Unlike NEDC and WLTP, the Real Driving Emissions tests will measure pollutants such as NOx while the vehicles are driven on the road – thus demonstrating whether the results of the lab tests can be reproduced under normal conditions.

Which CO2 value is being used as the basis for taxation?

There has been some confusion about the CO2 value that should be used as a basis for taxation (VAA and deductibility in corporation tax) for vehicles inspected under the WLTP cycle.

The NEDC (2.0) value will remain until 2020. It was also intended that the DIV would always mention this CO2 value on the registration certificate. For technical reasons in the pre-registration of vehicles (see Febiac's full explanation in the attachment), however, in some cases the full WLTP value may end up on the registration certificate and therefore not the (reduced) NEDC 2.0 value.

The only correct CO2 value that serves as the basis for taxation can be found on the certificate of conformity in section 49.1. (Section 49.4 also mentions the full WLTP value for WLTP-approved cars, but this is currently not relevant for tax purposes). More information can be found here in the official communication of Renta.

Will my fuel consumption increase?

The WLTP will result in higher g/km CO2 values compared with those of equivalent vehicles that have already been tested according to NEDC, simply because the new test is longer and more rigorous. This is especially true for cars with small-volume turbo engines that are currently popular in the fleet business, and for which the emissions are estimated to increase by up to 25 percent. The higher CO2 value does not mean that the fuel consumption has increased, but simply allows consumers to predict the actual fuel costs for a vehicle more accurately. This does mean however that many cars will no longer meet current sustainability objectives, and that fleet managers can expect higher vehicle taxes, which are based on CO2 emissions in many countries.


What can you do?

 1. Adapt your car policy

 For many employers, company cars are an important tool for attracting and motivating top employees. Fuel consumption and CO2 values have a big impact on the vehicles employees choose to drive. With the introduction of WLTP testing, average CO2 values are expected to rise for cars from all manufacturers. Alphabet currently expects an overall increase in WLTP CO2 levels of up to 25 percent, which means that many models will fall out of selection, if the car policy remains unchanged.

Fleet managers will be able to assess the full impact of the WLTP test on their current lists as soon as the official WLTP emissions data is made available by the relevant carmakers. Companies that have included a CO2 limit in their car policy will need to analyse, reconsider and even adjust this limit accordingly. To ensure that employees have access to the vehicles they want and are used to driving, a CO2 limit of for example 120 grams would need to be increased to at least 150 grams. Also, since WLTP tends to favour stronger engines, vehicles that used to be less popular might come back into focus.

2. Act greener

Alongside revising the policy limits, fleet managers can also update the vehicle selection to offer employees only those vehicles with the best emission performance under WLTP. Such a change should be communicated to employees with the appropriate reasoning to ensure their satisfaction and support. Climate change and environmental protection are hot topics that many employees will relate to, so this is a great opportunity for companies to gain support for CSR or environmental commitments. Fleet managers can also adjust the additional equipment available for certain cars (i.e. smaller wheels, no sunroof, etc.), as the fuel consumption and CO2 values will now also take this equipment into account.

Ultimately, the changeover to WLTP offers companies a fantastic opportunity to present themselves both internally and externally as environmentally friendly and future-oriented.

3. Increase the fleet’s electric share

Instead of relying on smaller or less equipped vehicles, fleet managers can also use the changeover to WLTP to replace some cars with combustion engines with all-electric vehicles or plug-in hybrid models. Switching to cleaner models is not only good for the environment – it can even save the company money in the long run with lower running costs for fuel and vehicle taxes than conventional cars. Alphabet provides fleet operators with holistic support through AlphaElectric, a comprehensive approach for successfully incorporating electric and hybrid vehicles into traditional diesel and gasoline fleets. AlphaElectric’s Mobility Consulting Tool (MCT) – a software developed by Alphabet – demonstrates with clear facts and figures if and how electric cars can be integrated into the fleet, smartly and seamlessly. The recently enhanced MCT gathers real data on a company’s driving behaviour by means of GPS loggers installed in the cars. With the MCT, Alphabet can then offer transparent recommendations for suitable electric vehicle alternatives, consult on charging infrastructure, and calculate the potential decrease in CO2.


  • Si uniquement valeur de NEDC2.0 sera imprimée sur le document: NEDC 2.0 sera de vigueur
  • Si uniquement valeur de WLTP sera imprimée sur le document: WLTP sera de vigueur
  • Si les valeurs de NEDC 2.0 et WLTP seront imprimées: choix libre en fonction du régime fiscal le plus avantageux par le consommateur/le client

La valeur exacte de NEDC 2.0-CO2 est notée dans la rubrique 49.1 du certificat de conformité. La valeur de WLTP-CO2 est notée dans la rubrique 49.4.

Quelle CO2 et consommation sont visibles dans les offres et dans les systèmes?

C’est toujours la valeur de NEDC 2.0 pour l’émission CO2 et la consommation. Bien que tous les véhicules soient testés en WLTP, la fiscalité actuelle est toujours basée sur NEDC 2.0. 

Quand pouvez-vous (rece)voir et calculer la valeur exacte de WLTP?

Alphabet construit actuellement un “service WLTP” (pour rechercher en ligne les valeurs de CO2 fiables chez les importateurs belges, car chaque configuration aura un résultat de WLTP spécifique). Les importateurs belges sont en train de coder tous les véhicules, options, packs.

Alphabet vise à mettre en production ce « service WLTP” au cours du 4ième trimestre de 2020.

Alphabet is here for you, just get in touch with us and let’s navigate the changeover together!

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