The Worldwide Harmonised Vehicle Test Procedure (WLTP) will be used for vehicle type approval in the European Union. It introduces a new test cycle and a new procedure for measuring fuel consumption, CO2 emissions and regulated pollutants for vehicles under standard (laboratory) conditions.
It will gradually replace NEDC.
Thanks to sound technological choices made in anticipation of the regulations, Citroën is ready for this new WLTP approval protocol, mandatory for all passenger vehicles from September 2018.
One of the WLTP’s purposes is to more accurately reflect real driving conditions and the technologies with which vehicles are equipped during the approval process.
It sets out stricter test conditions and more dynamic driving conditions than the previous NEDC cycle dating back to the 1990s. It was designed using actual driving data, whereas the NEDC was based on theoretical driving profiles.
The WLTP also produces more precise data because it takes into account the specifications of each vehicle, including any and all optional equipment, which can have a significant impact on fuel consumption and CO2 emissions.
Thanks to sound technological choices made in anticipation of the regulations (SCR in diesel and GPF in petrol), Citroën is perfectly ready for the new WLTP approval protocol which more closely mirrors customers’ actual use.
In addition, to better inform its customers, Citroën publishes the consumption data of its models on its website since 2016 and the NOx emissions data since March 2018 in real driving conditions, based on a protocol developed with NGOs (T&E and FNE) and certified by an independent third party (Bureau Veritas).
Customers can also set up their car and usage parameters to check consumption under their own use.
From September 2018, in addition to the WLTP protocol, the manufacturers will have to measure the emissions in Real Driving Situation (RDE) of all their vehicles sold within the European Union, as well as in Switzerland, Turkey, Norway, Liechtenstein , Israel and Ireland.
Citroën performs this type of test using a PEMS system.
A car equipped with a Portable Emissions Measurement System (PEMS) is driven on public road. The PEMS collects data to verify that the legislative caps for pollutants are not exceeded. It provides complete real-time monitoring of major pollutants emitted by vehicles (NOx, PN).
The collected data are analyzed to verify that the driving conditions fulfill RDE requirements and that emissions are within acceptable limits.
What is an approval procedure?
It is a standardised set of parameters, including the test cycle, used for vehicle approvals. Having a single approval procedure makes it possible to compare the fuel consumption and CO2 emissions of different vehicles. The NEDC (New European Driving Cycle) has been in force since 1992. It will be replaced by the WLTP for all vehicle types from September 2018.
Why change the approval procedure?
The former NEDC procedure was deemed unrepresentative of how our customers actually their vehicles. The fuel consumption data we disclose going forward, measured with the WLTP, will be closer to the actual consumption levels observed by our customers.
The new procedure takes into account the weight of the equipment, which was not the case before. How is that done?
The weight of equipment is actually taken into account in the levels CO2 emissions determined via the WLTP. This is a regulatory requirement. Our networks and our brands’ websites will have a tool to determine CO2 emissions depending on our customers’ choices in terms of vehicle configuration and equipment.
What are the differences in consumption between the former NEDC test cycle and the WLTP?
The reported WLTP consumption amounts exceed the amounts measured in the NEDC by approximately 25% to 30%. The impact of the driving cycle depends directly on the displacement of the engine. Big cars have a smaller gap than small cars.
Will my fuel consumption increase with the WLTP?
There will be no impact on your car’s consumption with the new WLTP values. The WLTP will only result in a higher CO2 g/km value for the same vehicle than under the NEDC because it is a more rigorous and longer test, meaning simply that the WLTP better reflects the actual situation. In other words, the higher CO2 value does not mean an increase in fuel consumption, but rather a more realistic CO2 measurement due to the change in the way vehicles are tested.
When do you plan to release all of the new CO2 values?
The regulations require that CO2 values be displayed according to the WLTP measurements from 1 January 2019.