Real Driving Emissions (RDE):

Although WLTP will deliver real improvements to the testing regime, it is still a laboratory test and cannot take into account driver style, traffic conditions, weather, gradients or load of the car into its calculation. All of these factors have an impact on the consumption and emissions performance of the vehicle. The RDE test will support in providing customers with this insight.

The RDE test is carried out by fitting Portable Emissions Measuring (PEMS) equipment to the car to record exhaust emissions. The test follows a standardised set of parameters, including:

•     low and high altitudes
•     year-round temperatures
•     additional vehicle payload
•     up- and down-hill driving
•     urban roads (low speed)
•     rural roads (medium speed)
•     motorways (high speed)

The results of the RDE test will be used to validate the emissions and consumption values identified as part of the WLTP testing process.