Manufacturers of electric cars always indicate in the characteristics of the vehicle its mileage per battery charge, but this concept is extremely loose. At least because in each of the regions of the world where these electric cars are designed, assembled and sent for sale, their own methods for assessing this very power reserve – someone allows local companies to have sky-high mileage on a single battery, and someone tries to be closer to reality. It’s time to understand the features of these techniques and understand why a pickup truck from Ford almost gives out the declared distance, but a Chinese crossover does not.
Although this abbreviation stands for New European Driving Cycle (“New European Driving Cycle”), it does not dare to call it a new language – the last important update of the measurement technique was received in 1997, and was formed back in 1970. Accordingly, it was aimed primarily at internal combustion engines, and not at electric cars, because then they simply did not exist. And this technique is extremely strange – the test of the car lasts only 20 minutes on a test bench, where the vehicle travels 11 kilometers (66% with imitation of city driving and 34% of imitation of highway driving). The average speed in this test is only 34 km/h.
Probably, no one needs to explain that at a speed of 34 km / h for 20 minutes, it is simply impossible to estimate the exact fuel consumption of a car more or less accurately. However, this was not required – buyers of internal combustion engines always needed to know how economical their car was, and NEDC made it possible to estimate this parameter, albeit approximately. Of course, the real fuel consumption was underestimated, but in Europe everyone used this technique, so everyone had an underestimated consumption, so the situation remained balanced. Naturally, NEDC is not suitable for electric cars at all, since the power reserve is important for the buyer, and not how much energy will be spent per 100 kilometers. And although for some time, electric cars were still “measured” according to NEDC until 2017, at the moment the technique has been completely replaced by WLTP.
Although the Worldwide Harmonized Light Vehicles Test Procedure has “worldwide” in its name, in fact it was created in Europe and beyond its borders, if they are used, it is extremely rare. At the same time, in the process of developing a new methodology for testing cars, first of all, the goal was to estimate the amount of carbon dioxide emissions into the atmosphere – naturally, it was “sharpened” for internal combustion engines, and not for electric cars, since mainly German concerns have so far abandoned their engines were not in a hurry. And, of course, in the end, the range accuracy of electric cars according to the system that was created under the internal combustion engine turned out to be extremely low.
The testing methodology is almost exactly copied from NEDC – at the test stand, the car drove 23.25 kilometers at an average speed of 46.5 km / h, the test run time was increased to 30 minutes, plus imitations of stopping at traffic lights appeared. Of course, with a tougher methodology compared to NEDC, the fuel consumption of all ICE cars increased, while the range of electric cars decreased. And although now this power reserve looks more realistic, there is no need to talk about any accuracy, just, unlike NEDC, the numbers are now less attractive.
The Europeans were very active in promoting their new WLTP methodology, but it was not accepted in the USA – instead, the Environmental Protection Agency (EPA) created its own methodology called the Federal Test Procedure (FTP-75), which is by far the most honest in relation to electric cars. The reason is extremely simple – if in Europe WLTP was developed with an eye on the mastodons of the market and their specific needs, then in the USA the independent EPA agency does not depend on GM or anyone else. As a result, they managed to create an extremely realistic test mechanism, which is similar to how an ordinary person uses an electric car in everyday life.
To begin with, the car is fully charged in the evening, and then left until the morning, after which they simulate a “cold start” – starting and driving without “warming up” and other tricks. Moreover, while driving, the air conditioning must be turned on, and the driving dynamics are much faster than what is considered the norm in Europe. For example, according to FTP-75, the acceleration rate from standstill to hundreds is twice as high as that of WLTP, since the American agency believes that no one drives at a speed of 45 km / h. It is precisely because of more realistic standards that the range of American electric cars is always lower than that of European ones. On the other hand, he is honest.
In Japan, one of the most progressive countries in the world, including in the field of electric cars, back in 2010 they created their own assessment method called JC08, which, however, was initially too loyal. The fact is that the car travels only 8.17 kilometers during this testing cycle, and the duration of the race is 20 minutes. At the same time, the average speed of a vehicle is only 24.4 km / h – naturally, in real life, no one drives at such a speed. In addition, according to the JC08 scoring system, it is allowed to take into account the results with the so-called “soft start”, plus there is an imitation of stopping at traffic lights. As a result, almost a third of the testing time, the car literally stands still.
In this case, the tests are carried out on stands in enclosed spaces, and not on the track. Given this moment, almost 6 minutes of downtime and a smooth start, it turns out that the JC08 allows you to write the maximum range of all possible in the car’s characteristics – even in China with WLTP, the range is not so impressive. On the other hand, in Japan, no one complains about this, since their testing methodology is as close as possible to driving in the city, taking into account traffic jams, frequent stops and low speed. The Japanese do not drive around the city at 100 km / h, almost do not drive outside the city (all of Japan literally consists of megacities) and for their driving style, the JC08 looks like a worthy option.
China, which is quite expected, has its own testing methodology for electric cars, which is called CLTC and is somewhat similar to NEDC. During testing, the vehicle “drives” a segment of 14.48 kilometers, which is divided into 11 rather short distances – 7 of them the car passes at low speed, 3 at medium speed and only one at maximum speed (114 km / h). Accordingly, for 30 minutes the electric car moves at an average speed of 28.96 km/h, and 22% of the entire test time the car is completely idle (imitation of stops in traffic jams and at traffic lights). Like the Japanese, this is a fairly loyal technique for estimating the power reserve.
In addition, and not least, they test an electric car in a closed room with a constant temperature of 23 ° C – there is no air resistance during movement and battery degradation due to low or too high temperatures. In real life, such ideal conditions are simply unrealistic to achieve, so the CLTC power reserve is absolutely always too high. However, this allows marketers in the Chinese auto industry to advertise their cars with impressive mileage on a single charge, and if you drive only around the city, you can achieve almost the same results.
The real power reserve is simply impossible to estimate
We can safely say that the US range estimation methodology works best – cars are tested quite severely according to FTP-75, which allows you to get the result closest to reality. And in Japan, which is practically one continuous metropolis, JC08 also turns out to be almost true. Chinese and European methods are too loyal to the local auto industry for obvious reasons, so it often turns out that “on paper” a crossover should travel 600 kilometers on a single charge, but in reality it hardly manages to overcome 400 kilometers, and even at a speed of 80 km/h.
However, it should be said that none of the methods will give accurate information. There are many factors that affect the range of an electric car: wind speed and direction, weather conditions, body streamlining and wheel design, air and road surface temperature, rubber quality, a person’s driving style, the number of stops at traffic lights and traffic jams, even air conditioning, multimedia system or smartphones on charge. With all the desire to create a methodology that could take into account all these parameters and be universal, it is simply unrealistic. You just need to understand that the American and Japanese systems give the greatest accuracy in their region, and you should always subtract 20-30% from the power reserve of an electric car from China and Europe.
Source: Trash Box
I am a journalist and author who works for World Stock Market. I have written about the stock market for years and I love it.