Under conditions defined by EU law, the Worldwide Harmonised Light Vehicle Test Procedure (WLTP) is a laboratory test is used to measure fuel consumption and CO2 emissions from passenger cars, as well as their pollutant emissions.
The old lab test – called the New European Driving Cycle (NEDC) – was designed in the 1980s. Due to evolutions in technology and driving conditions, it became outdated. The European Union has therefore developed a new test, called the Worldwide Harmonised Light Vehicle Test Procedure (WLTP). The EU automobile industry welcomes the shift to WLTP and has actively contributed to the development of this new test cycle.
While the old NEDC test determined test values based on a theoretical driving profile, the WLTP cycle was developed using real-driving data, gathered from around the world. WLTP therefore better represents everyday driving profiles.
The WLTP driving cycle is divided into four parts with different average speeds: low, medium, high and extra high. Each part contains a variety of driving phases, stops, acceleration and braking phases. For a certain car type, each powertrain configuration is tested with WLTP for the car’s lightest (most economical) and heaviest (least economical) version.
WLTP was developed with the aim of being used as a global test cycle across different world regions, so pollutant and CO2 emissions as well as fuel consumption values would be comparable worldwide. However, while the WLTP has a common global ‘core’, the European Union and other regions will apply the test in different ways depending on their road traffic laws and needs.
Testing – What are the differences between NEDC and WLTP?
Passenger vehicles (M type and Category N1 (i)):
- From September 2017, all new model introductions will be subject to WLTP type approval and Real Driving Emissions (RDE) testing
- From September 2018, all new registrations will need to comply to WLTP type approval
- From September 2019, all new registrations will be subject to RDE testing
Light Commercial Vehicles (Categories N1 (ii), N1 (iii) and N2):
- From September 2018, all new Light Commercial vehicle model introductions will be subject to WLTP type approval and Real Driving Emissions (RDE) testing
- From September 2019, all new registrations of Light Commercial Vehicles will have received type approval under WLTP and all new registrations will be subject to RDE testing
For further information on WLTP, please click here