Background: WLTP in a nutshell

The new test cycle WLTP, that the NEDC is replaced, turn on the car market at this time, quite on its head. Reason to put him on a simple, clear way to summarize in a nutshell. Okay, a kokosnotendop maybe.

Earlier we went into detail on the WLTP, but for whom that story all too technical and in depth, we will explain it here what easier.

WLTP stands for Worldwide Harmonized Light vehicle Test Procedure and replace the NEDC (New European Driving Cycle). Where the NEDC is performed on a chassis dynamometer, the WLTP is indeed in practice be measured. Nevertheless, it is still the rollers, whereby that part is a lot tougher is made.

To the rollers to start with: compared with the NEDC should be in the WLTP a greater distance to be driven. In addition, the speed differences in the prescribed cycle natuurgetrouwer, the circumstances more accurately defined and the margins smaller.

More interesting is that cars now on the road to, so it can be tested on the dynamometer measured values also in the practice. That part of the test is T-test (Real Driving Emissions-test). To that end a mobile measuring device on the hitch mounted PEMS (Portable Emissions Measurement System) called. Such a device is limited in size and weight and therefore less accurate than the extensive laboratory setting. Blame that inaccuracy is, moreover, the mobile device only before and not during the measurement can be calibrated.

Therefore, there is a so-called conformiteitsfactor on the system and that is at this time is 2.1. Thus, the PMES readout is the current upper limit of 80 mg/km NOx has been extended to cover 80 x 2,1 = 168 mg/km. That space is not infinite: the conformiteitsfactor in January 2020 down to 1.5, so that the upper limit in the practical measurement but 120 mg/km.

Manufacturers may REDUCE their own course, determine, but within strict standards. The total test must be at least one and a half to two hours. From that time, 34 percent urban (60 km/h), 33 percent buitenweg (60-90 km/h) and 33% highway (90-145 km/h, of which a minimum of five minutes above 100 km/h). Each part should be at least 16 km and the difference between the start point and end point may be up to a hundred meters. The ride should be done under the supervision of an independent review body, such as the RDW.

The WLTP has been the case since september 2017 for new on the market to appear in cars, but since september 2018 must every new car WLTP-approved. Only uitloopmodellen still have a years respite.

The consequences of this we notice lately a lot. Many of the models and/or versions disappeared, forced to the price list, because they are in the RDE test, high NOx emissions are found to have. Other models are now more expensive because they are in the new rollenbanktest higher values of CO2 score, with all the consequences for the bpm. In particular, small, cheap models suffer from it, because the same price increase there more hurt than in expensive cars.

Though the WLTP by now established, for the time being, we are not yet completely of the NEDC. The European vlootgemiddelde (the average CO2 emissions of all sold in Europe, cars of a brand in a year), that since 2015 a maximum of 130 g/km may be, is determined according to the NEDC standard, and that remains so until in 2020 the bovengrans drops to 95 g/km. Then, from the existing data of both methods, a conversion factor is determined and is the NEDC final history.