知名電動車網路媒體 InsideEVs 有篇報導回應這個結果。
原文網址：
https://insideevs.com/news/365941/what-car-different-results-epa/
原文：
We searched for explanations. And here are the answers.
When we wrote to you about the real-life EV range ranking made by the British
magazine What Car?, we got curious by huge differences in what the magazine pr
esented and what EPA discloses with its ratings.
Four vehicles made us wonder: the Tesla Model S75D and the Model X100D, whic
h lag behind by around 50 miles of range, and the Jaguar I-Pace and the Kia Ni
ro EV, which get around 20 miles more than in EPA ratings. Why? One explanatio
n is that the differences relate to WLTP and EPA cycles, but we found out ther
e’s way more to it than it seems. Most of all, it has to do with electric car
s being entirely different animals from ICE cars.
We contacted Steve Huntingford, editor of咗hat Car?, to ask him what caused su
ch differences. Hard feelings due to the Independence? A protective approach t
owards Jaguar and the Korean brands? Joking aside, it has to do with each manu
facturer’s priorities for him.
“The nature of the (European) WLTP cycle is different from the (US) EPA cycle
. The EPA test emphasizes long-distance cruising, which of course is more comm
on in the US, with its geographic nature. WLTP is about shorter, start-stop dr
iving, more common in Europe,” said the editor.
Huntingford believes that the Kona (Kauai, in Portugal) and the Niro EV are re
latively small cars, more European focused. So they would have been tuned to g
o well in WLTP tests. Tesla models, on the other hand, would be more focused o
n the US, and thus tuned to perform better in EPA cycles. The I-Pace adopts a
more neutral approach towards the two test cycles.
We have then spoken to some engineers and to Tesla about this explanation. For
the engineers, although they think it is feasible that different cycles have
an impact, the real problem is testing electric cars as if they were combustio
n-engined vehicles.
While ICE cars are also affected by aerodynamics, weather conditions and mass,
electric cars are way more sensitive to that. They are made to be as efficien
t as possible due to the fact that their battery packs, although with more ran
ge than ever in history, are still limited. And take longer to get back to bus
iness.
One good example of that was Jason Fenske’s road trip with his Model 3. He tr
aveled 1,963 miles on 560 kWh. Or on the equivalent to the energy contained in
a 16.6 gallons gas tank. That’s a little less than the 18 gallons a 2019 Chr
ysler 300 fuel tank can hold. Can you imagine this sedan running 2,000 miles o
n a single gas tank? Neither do we.
With that sort of efficiency, anything can make the car present a longer or sh
orter range. More wind or less. Temperature. Traffic. The way the guy behind t
he wheel drives. Electric cars try to compensate for that with regenerative br
aking and other strategies.
Most of the engineers we interviewed preferred not to speak on the record. The
y claim to have no idea how What Car? conducts its testing despite the compreh
ensive description the magazine offers. Fair enough, but they were unanimous i
n stating electric cars should be tested until their batteries are completely
depleted.
And why is that so? Because this would be the only way to check what the energ
y recovery systems in an electric car can do. Tesla cars have battery packs fo
r longer ranges, which implies their regenerative brakes only start to make a
difference when the charge is not at its full capacity anymore.?
Cato Standal, who had his Tesla Model S battery pack replaced in Norway, remem
bers this behavior as the strongest indication his new batteries were restrict
ed by software. "What makes me be 100 percent certain that this is a software
limitation is that now I have full regeneration even if the battery is fully c
harged. If the battery was 100 percent charged, you would not get more power,"
he told Tek.no.
Some of the engineers we spoke to go even further and say tests with electric
cars could never be performed on a track. For them, they should be done in lab
s with dynamometers, under very controlled conditions. That would be the only
fair scenario to compare different vehicles.
This is precisely what EPA does. And the fact that its results are different f
rom the ones presented by What Car? could be an indication that, no matter how
professional our colleagues are in dealing with the tests, they just should n
ot be performed as they are with ICE vehicles.
There’s more to it. The idea that different cycles would present very differe
nt results due to longer or shorter distances seemed strange to Ricardo Takahi
ra, a member of the SAE Brazil Technical Board for Electric Vehicles.
“Electric vehicles do much better at short distances than on the road. An EV
that is calibrated to perform well in long distances theoretically will do eve
n better in short ones. It needs less energy to move at low speeds with little
air resistance”, said Takahira.
We have also spoken to EPA and the agency also recommends all tests are made i
n labs with dynos. Not surprisingly the way it performs its tests. Over-zealou
sness? Perhaps when it relates to combustion-engined cars, but not with EVs du
e to the energy regeneration's influence.
Tesla also responded to our inquiries and said the following:
“These results are wrong and not reflective of the WLTP results determined by
European regulators due to the fact that What Car? conducted an abridged test
without fully depleting the vehicle’s battery. Using only a fraction of a ca
r’s total range and attempting to extrapolate that result as a proxy for its
full useable range is simply incorrect.
We also believe the vehicles included in the tests were not tested under the s
ame exact conditions, which means the test results cannot be directly compared
. True comparative results can only be achieved under lab conditions, which is
why standard test procedures like WLTP are used to measure and compare vehicl
e range.”
Magazine tests probably could never be conducted in labs, due to costs. Newsro
oms increasingly count on fewer people doing more things, which makes a long t
est very difficult for a journalist to perform. Anyway, when it comes to elect
ric vehicles, it seems there is no other choice.
Although this has happened with What Car?, it could happen to any other specia
lized magazine. It probably is happening with many around the world that are n
ot aware of the unique characteristics of electric cars.
What Car? will probably want to prove their methods are solid by doing at leas
t some of them as recommended by Tesla and the engineers we spoke to. Or else,
until a full charge ends completely. With independent parties to certify ever
ything was done by the book. And it may eventually prove its point, despite do
ubts from the people we interviewed.
While What Car? does not do that, we recommend our readers to pay attention to
test methods regarding energy consumption. If they are not performed until th
ere is no single Wh left on the battery pack, stick with official rankings, su
ch as EPA's. This probably is the safest way to check the efficiency of an ele
ctric car when compared to others.
重點翻譯：
原文指出 Tesla Model S/X 的 EPA 結果比雜誌測試的多了50英里，而Jaguar I-Pace卻
是反而雜誌比 EPA 多20英里。
一個可能性是雜誌的測試比較接近歐洲人開車習慣，把重點更多放在短程的城市駕駛，而
美國的 EPA 為了模擬美國使用狀況，更著重長途的遠程續航力。
還有就是因為電量的限制，電動車都是設計成極度省能源的車，Model 3實測開1963英里
花了560度，那個電量換算成汽油的能量密度相當於16.6加侖(62.8L)，有哪台油車滿缸可
以開兩千英里的呢？在效率這麼高的狀況下，任何一點變數都有可能對電耗造成很大的影
響，比如風速、溫度、車流量、駕駛習慣。因此電動車靠煞車動力回收來抵抗這些外來因
素。
所以，多數工程師都建議實際續航力應該真的測到電池用完，而不是只有31.2公里，這樣
才能真正考驗電動車的動力回收能力。
另外有一些工程師認為要真正比較不同電動車的能力，一定要在封閉測試環境才公平。
特斯拉官方回應：「這個測試結果是錯誤的，而且也不符合 WLTP 的測試結果，因為 Wha
t Car? 雜誌測的距離太短，並沒有實際上把電池電量用完，只拿很短的距離來估電動車
實際的續航力是不對的。
我們相信這個測試也沒有很嚴格的保證不同車子測試的條件環境是相等的，所以結果無法
比較。要公平的比較不同車輛必須在實驗室比，這也是為什麼要有 WLTP 這種標準測試。
」
個人心得：
我覺得這個測試最嚴重的問題就是要比續航力竟然不直接從100%開到0%，而是只開31.2或
是62.4公里就停。很有可能這短程內根本不需要什麼煞車，所以沒辦法比較各家的動力回
收能力。要比續航力還是把電池開到沒電吧！
只開短程公里，當然是那些歐洲才買得到的小車會比較吃香，電耗較低，但那些車子根本
跑不遠。BBC的知名英國車媒Top Gear實測I-Pace也不到322公里。
英國的研究還是看看就好。