WLTP: Frequently Asked Questions

WLTP: Frequently Asked Questions

What are the consequences of the new WLTP measurement method? The emissions and fuel consumption of new cars are measured differently (read: more realistically) with the introduction of the WLTP. As a result, the BPM (tax) on cars may increase. The ANWB believes that consumers should not be disadvantaged by this new measurement cycle.

What is the WLTP? WLTP stands for Worldwide Harmonised Light Vehicle Test Procedure. It is a test used to measure a car’s exhaust emissions. The measurement is carried out during the type approval of a car to see if it meets the applicable emission standards. WLTP replaces the outdated NEDC method. The results of the NEDC test increasingly deviated from real-world emissions and consumption. Hence, the call for a more realistic test regarding driving cycle and resistances. This ultimately resulted in the WLTP, a more rigorous test with higher CO2 emissions. Because it is also a laboratory test, it remains possible to compare cars with each other.

When does the new WLTP come into effect? From September 1, 2017, all new car models for type approval are measured according to the WLTP test. For existing models, this requirement applies from September 1, 2018. This means that all newly produced cars after September 1, 2018, are measured according to WLTP.

What is CO2MPAS? All new cars sold in Europe together must meet a CO2 target of 95 g/km based on NEDC values by 2021. With the introduction of WLTP, a problem has arisen. To check whether the CO2 target is being met, the European Commission has developed the CO2MPAS calculation tool. This tool calculates an NEDC value from the measured WLTP value for each individual car. If the calculated NEDC values are higher than expected, this may lead to adjustments to CO2MPAS.

The CO2MPAS calculation tool is thus developed to monitor the total new car sales in Europe for their CO2 emissions. In the Netherlands, this tool is now used to calculate an NEDC value from the WLTP value for determining the BPM.

How is the WLTP measured? Several differences between the WLTP and the NEDC test are:

• The WLTP driving cycle on the test bench is much more dynamic and thus more realistic than the tame NEDC cycle. There is more braking and accelerating and higher speeds, as shown in the graph. The WLTP cycle has four phases: slow, medium, fast, and very fast.

• The driving resistances set on the bench are much higher and more realistic than with the NEDC, where the car could be fully prepared for determining driving resistance.

• The WLTP cycle lasts about half an hour, about 10 minutes longer than the NEDC method. This reduces the influence of the cold start.

• In the NEDC, there is one CO2 emission for an entire car family, regardless of body shape and whether or not options are present. In the WLTP, options do play a role. All engine-transmission variants of each car are tested separately in the basic and the most equipped version. The latter has extra driving resistances due to higher weight, among other things. The basic version is called WLTP Low, and the most equipped version is called WLTP High.

• Depending on the options present, the CO2 value for each car is determined individually from the WLTP Low and High values via interpolation.

WLTP as the basis for BPM From July 1, 2020, the WLTP CO2 value will serve as the basis for determining the BPM. The WLTP CO2 value is much higher than the old NEDC value. To make the transition budget-neutral, as promised by the government, BPM rates have been reduced as of July 1. This should apply to the average car. For the individual car, there can be a (significant) difference in BPM.

Options and WLTP Is it true that for each option for a new car, it is determined whether the CO2 increases (and thus the BPM)?

Yes, the WLTP measurement determines whether an option leads to more CO2 emissions (higher consumption). This is due to, for example, increased weight or different aerodynamics of the car. When WLTP becomes the basis for determining the BPM, you will determine extra BPM for such options. The NEDC did not take these options into account for determining CO2 emissions and fuel consumption.

Can a dealer give me a reasonable price quote? When a car is produced, it receives a ‘birth document’ stating the exact CO2 emissions of this specific car, including any options. Based on this, the BPM is calculated. For standard versions whose CO2 emissions are known, a dealer can provide a price quote in advance. If it becomes more complex, many brands will use so-called car configurators where options can be selected to determine the correct CO2 emissions and thus the BPM amount and price.

Sometimes many options can be selected in various combinations, making it difficult to determine CO2 emissions and price. A very fast internet connection between the factory and the dealer can then provide a solution. Whether this is necessary and used by dealers, we do not know (yet).

Higher consumption due to stricter emission requirements The Euro 6 emission standard is being introduced in phases, with the stricter WLTP measurement from Euro 6c. But that’s not all:

• Direct injection gasoline engines are also allowed to emit fewer particles. To achieve this, new gasoline cars are equipped with particulate filters. This leads to higher gasoline consumption and thus higher CO2 emissions.

• And with Euro 6d, the WLTP driving cycle, which is performed in the laboratory, is extended with a real-world driving test. This RDE (Real Driving Emissions) test focuses mainly on NOx and particle emissions. It has been shown that these emissions are much higher in practice than in the laboratory test. Achieving low NOx emissions requires technology that often comes with (significantly) higher consumption and thus CO2 emissions.

In summary: stricter emission requirements lead to higher CO2 emissions and thus, with an unchanged tariff system, to higher BPM.

What is Euro6d-Temp? Before the definitive Euro6d emission standard comes into effect, we have a temporary requirement, Euro 6d-Temp. Under this emission requirement, NOx emissions in the RDE real-world test may be 2.1 times higher than on the test bench. Later, with the definitive Euro 6d, this factor is reduced to 1.5. For particles, a factor of 1.5 applies in both cases. Several car manufacturers want their models to already comply with the upcoming Euro 6d requirement, partly with a view to future environmental zones.

Still calculating back to the old NEDC standard? Why is the WLTP calculated back to NEDC standards until 2021? The WLTP measurement has already been implemented for current new cars, right? Yes, but this way you can continue to see whether cars meet the 95 g/km limit that applies in 2021. The CO2 targets that manufacturers must meet from the EU by 2021 are based on the old NEDC test.

I hope this helps! If you have any more questions or need further assistance, feel free to ask.