2023 Author: Eric Donovan | [email protected]. Last modified: 2023-05-21 15:44
The NEDC consumption cycle was criticized: it simply had nothing to do with realistic driving conditions. In September 2017 the WLPT will come. Will everything get better now?
Drivers will slowly have to get used to a new shortcut. From September 2017, the new WLTP test procedure for determining the standard consumption will gradually replace the previous NEDC (New European Driving Cycle). WLTP stands for Worldwide Harmonized Light Vehicle Test Procedures.
Since March 2014, in addition to the European countries, Australia, China, India, Japan, South Korea, South Africa and Turkey have agreed on this new, globally harmonized driving cycle. This is to ensure a uniform standard and better comparability for exhaust emissions and fuel consumption in the increasingly international vehicle market. Important for consumers: The new standard should be much more practical than the NEDC.
Better reproducibility of the tests
Like the NEDC, the WLTP test is carried out under laboratory conditions for better reproducibility and comparability of the test results. Defined room and climate specifications also apply here. The test starts at an air temperature of around 23 degrees. What is new is that the vehicles are divided into three weight or performance classes: up to 22 watts per kilogram, up to 34 watts per kilogram and from 35 watts per kilogram.
The new standard also takes into account markets where small vehicles dominate. Common models in the EU almost exclusively belong to class three. This differentiates itself - more for other markets - by dividing it into vehicles that drive faster or slower than 120 km / h. The tested cars are no longer weight-optimized as before. These are models with the usual standards such as air conditioning on board. The tank is now 50 percent full instead of 40 percent.
Standard test drove faster
Also new: The standard test is now run longer and faster. So far it was over at 120 km / h. Measurements are made in four phases up to 60, up to 80, up to 100 and over 130 kilometers per hour, in order to simulate city traffic, cross-country and motorway journeys. The new cycle is also more than twice as long and now covers 23 instead of 11 kilometers. The travel time has been increased by ten to 30 minutes. The average speed has also increased. It is now 47 km / h instead of 33.4 km / h.
What do the new consumption results look like on the test bench? To this end, TÜV Süd carried out a NEDC-WLTP comparison. The astonishing result: the new test procedure does not always generate higher average consumption. According to the WLTP, a Mercedes C 180 drove half a liter more economically than according to the old test procedure. Pascal Mast, head of the TÜV Süd exhaust gas laboratory network, sees vehicles with larger engines at an advantage. You benefit from the longer test time - engine and transmission oils have reached their optimum operating temperature after 20 minutes - as well as from the new switching points defined under full load. The small, powerful turbos, on the other hand, show higher consumption according to the new measurement conditions than with the NEDC method.
The new standard is not yet applied to electric vehicles and plug-in hybrids. How the electric driving component is evaluated here has not yet been finally decided. So far, the purely electric drive counts as zero consumption and does not take into account the CO2 emissions during power generation. The NEDC cycle is not going to end very quickly. It will remain the standard reference value for a while: for example, vehicle manufacturers may continue to use the NEDC to determine the limit value of 95 grams of CO2 emissions set by the EU until 2020. (SP-X)
