What is WLTP and what is it for?
In September 2017, new vehicle certification rules were adopted in Europe. One of these changes is a new procedure for measuring harmful emissions and particulate matter emissions, fuel consumption, and determining the driving range of electric vehicles. The cycle, according to which bench tests will be conducted, is now called WLTP (Worldwide harmonized Light vehicles Test Procedure) - Worldwide harmonized Light vehicles Test Procedure. The new standard has been adopted in EU countries, Switzerland, Turkey, Norway, and Liechtenstein. The WLTP cycle corresponds as much as possible to the modern driving style of drivers.
What was it like before?
Before 2017, the NEDC cycle, the New European Driving Cycle, was adopted as early as 1970. Tests on the test bench according to this cycle last 20 minutes, during which the car travels 11 km, of which two-thirds of the time is simulated driving in the city, and another third - outside the city. The average test speed is 34 km/h and the maximum speed is 120 km/h. Following this cycle, the car accelerated to 50 km/h in the city in 26 seconds (funny, right?). And to 70 in the city - in 40 seconds. All this resulted in CO emissions and fuel consumption figures very far from reality.
What now?
In 2008, under the auspices of the UN, the development of a new cycle called WLTP began. Its final tests took place in 2014. The new cycle implied twice the distance - 22 kilometers. The average speed increased to 44.5 km/h, the maximum acceleration - one and a half times. The maximum speed is now 131 km/h. In addition, according to the WLTP standard, it is necessary to separately test the basic and maximally equipped version of the model with a certain engine.
Special conditions are set for evaluating the performance of electric cars and hybrid cars. Hybrid cars, for example, must have a fully discharged battery.
Plug-in hybrids are tested in four cycles:
- fully discharged battery
- partially charged battery
- fully charged battery
- testing in electric vehicle mode
WPTL electric vehicles are tested in two cycles:
- fully charged battery
- A 12-hour full discharge test to check the endurance of the battery.
The new auto-test conditions are much closer to real driving conditions.
What do others have?
The USA uses its own standard ETA FTP-75, which was last revised in 2008. The cycle takes into account the peculiarities of driving of the American motorist and due to its peculiarities, it is the most accurate. The car is tested for 31 minutes, during which it drives 17.8 km. During the cycle, the car makes 22 stops, and the total idle time is 20%. The maximum speed is 91 km/h, and the average speed is 35 km/h. The EPA cycle includes several sub-cycles:
- US06, which measures fuel consumption during sudden starts at stoplights and city traffic
- SC03, which measures consumption with the air conditioner on.
All this gives results that are much closer to reality. For example, the 2018 Nissan Leaf has the following mileage according to the data of different cycles
- EPA FTP-75 - 243 km
- NEDC - 378 km
- WLTP - 285 km in the mixed cycle and 415 km in the urban cycle (on 16” tires)
Conclusions
Now, seeing the new abbreviation WLTP in the price list, you will know that the measurements of mileage, consumption, and emissions for this model of the car were carried out according to the new, rather strict European rules. So there is a hope that in real life the mileage will be somewhere like this. However, in Ukraine, WLTP norms do not apply, so car sellers have the right to specify the technical characteristics of cars sold in Ukraine within the framework of the legislation in force in the country.
For example, one French automaker in Ukrainian price lists for all models indicated fuel consumption and CO2 emissions according to the directive 80/1268/EEC, adopted in 1980 (read NEDC). However, on the sites of European countries, these data are specified according to WLTP norms. And they are, of course, different.
It makes sense for Ukrainian motorists to look for the values of measurements according to the WLTP cycle. And even better, to be guided by average values between the strictest American EPA and the new European WLTP. In order not to be disappointed in vain.