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Tesla Cybertruck gets less than 80% of advertised range in YouTuber’s test::A YouTuber took Tesla’s Cybertruck on a ride to see if it can actually hit its advertised 320-mile range, only to find out that its could only reach 79% of the target. When YouTuber Kyle Conn…

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[–] [email protected] 267 points 10 months ago (19 children)

I hate Tesla and especially the Cybertruck as much as the next guy, but this was a highway test and that sounds like a completely normal result.

I own a Bolt EV which is rated for 259 miles of range. On the highway, that's more like ~220. That sounds bad, but the other side of it is that I get ~300 miles of range during my normal work commutes through the city. This is just how EVs are, the estimated range is based on a mixed test. EVs are backwards compared to ICE, you'll get ~20% less range than the EPA estimate driving highway speeds and ~20% more doing purely city driving.

[–] [email protected] 146 points 10 months ago (1 children)

I wrote this in another comment, but Tesla has been known for a long time to game EPA numbers. Here's an article from 2020 talking about it: https://insideevs.com/news/407807/eletric-car-real-world-range-tested/

Several get below their EPA numbers, but several cars also get higher. Tesla models all get significantly below their claimed mileage.

[–] [email protected] 14 points 10 months ago* (last edited 10 months ago)

The insideevs article reports 239 miles for a Model 3 Performance while clicking all the way through to the actual source of the testing "Whatcar" reported 324 miles for a M3 LR. What car indeed. I don't believe these low numbers.

I'm sure Tesla has been overly aggressive with the range numbers. Especially people in colder climates must be getting far less than advertised. But these low-effort articles are not the best of sources.

[–] [email protected] 38 points 10 months ago

It's worth noting that he recently did the same test, with similar temps, in the EV9 (which is also super inefficient on the highway), and got over the EPA range. IIRC most of his range tests exceed EPA numbers.

[–] andrew_bidlaw 19 points 10 months ago (5 children)

Why highways are worse than city streets? Highway doesn't have traffic jams, frequent stops when you just burn fuel\electricity to move a little further. It's just supporting the momentum of a car. With more than one gear it's trivial.

Maybe I don't understand something about e-cars, but from my experience I have wasted like 30% less of fuel just driving on highways from city to city for the same distance I drove in town.

[–] [email protected] 80 points 10 months ago (7 children)

In traffic, the largest reduction of efficiency comes from accelerating and the braking. You use energy to start moving (proportional to m V^2) and then you dump that energy into heat in your brakes to stop. The second comes from idling where you use energy to keep the engine rotating. As others have mentioned, EVs use regenerative braking so a substantial portion of the energy used to slow and stop the car is used to recharge the battery. EVs have no need to keep an engine running so unless you’re running the a/c there are minimal demands on a stopped/idling EV.

On the highway, you have the internal friction in the drivetrain to overcome, the constant deformation of the tires, and - most importantly - wind resistance, which is proportional to cd x rho x V2.

Cd (drag) and rho (air density) are low, but that V (speed) squared means driving at 75mph incurs 25x the energy use as driving at 15 mph. An EV gets no sage harbor here - plowing through a fluid (air) is essentially the same work.

To give you a sense of numbers, my vehicle (F150) gets less than 10mpg the 5 miles to my local pool/gym. The speed limit is 25 mph but there are stop signs every block or two. Lots of braking loss. On back roads with gentle curves and a 45 mph limit I get close to 30 mpg. That’s the sweet spot between overcoming transmission friction and air resistance. On the highway at 60 mph I get 22-23 mpg. At 78-79 mph I get 19 mpg. These are all generally on flat stretches using the 6 min average on my dashboard.

(Sorry for the long post…I’m an engineer and mechanical efficiency and aerodynamics are my happy place)

[–] [email protected] 28 points 10 months ago (3 children)

Ah so actually it's not that ICE vehicles are more efficient at highway speeds, it's that they are just SO MUCH worse in city driving that it only seems that way.

Interesting, I never thought about it that way

[–] [email protected] 12 points 10 months ago

It's both. Nearly all ICEs are specifically optimised to cruise at 50mph. Anything more or less will significantly reduce your MPG.

But yeah, slow speeds are really inefficient in an ICE.

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[–] andrew_bidlaw 11 points 10 months ago

Don't be. I'm happy to learn.

[–] [email protected] 10 points 10 months ago

Don't apologise, this was a great post!

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[–] [email protected] 41 points 10 months ago (1 children)

Traveling at high speeds just takes a lot of power regardless of fuel, but ICE cars are so inefficient in city driving it makes highways look good in comparison. 25-50mph might be more efficient, but every time you brake that kinetic energy is turned into waste heat, totally negating the benefit of driving slower.

EVs on the other hand have regenerative braking systems. Rather than using friction to slow the car down, they just use the motors by applying resistance to the wheels. The kinetic energy is used to charge the battery while slowing the car down. You get the benefit of slower speeds without much braking loss, so this is where EVs shine.

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[–] [email protected] 25 points 10 months ago* (last edited 10 months ago) (15 children)

Frequent lite braking allows the regenerative brakes to do all or almost all the work, meaning you recover a good chunk of the energy you’re using in city/stop-and-go traffic.

Infrequent braking or hard braking (which requires the service brakes) means less energy recovered, so shorter range.

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[–] [email protected] 16 points 10 months ago

Excuse the meta conversation but why are people downvoting what seems to be an earnest question?

Lighten up and just answer the question.

[–] [email protected] 10 points 10 months ago (1 children)

In addition to what atmur said, EVs don't have the baseline inefficiencies an internal combustion engine requires just to keep itself running. ICEs waste a huge amount of energy just running, which gets lost as heat, vibration, and noise. EVs have the advantage of being able to run just as much as needed, so you don't throw away huge amounts of energy at low speeds.

The efficiency curve of an ICE vehicle generally peaks somewhere around 70-90km/h, due to a combination of wasted energy at low speeds and gearing ratios. EVs peak much lower, generally in the 35-55km/h range. This is due to not having the low speed overhead of an ICE, but still being subject to high speed inefficiencies like rolling resistance and drag.

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[–] [email protected] 113 points 10 months ago (1 children)

I remember when top gear tested a Tesla and found the range they quoted to be wildly over estimates. Tesla lost the lawsuit.

[–] [email protected] 32 points 10 months ago (1 children)

That article's from 2012, before Elon Musk popularity took off, and yet you can already get a foreshadowing sense of Musk off the article:

Tesla Motors CEO Elon Musk called Top Gear "completely phony" and his company sued for libel and malicious falsehoods.

[–] [email protected] 22 points 10 months ago (1 children)

Top Gear were completely phony though, they purposefully ran the battery flat before the demo. This is known. Elons a douche but so is Clarkson.

[–] [email protected] 8 points 10 months ago (1 children)

Also, IIRC, Top Gear have always had a blase attitude towards their influence in the motor world. Given their reputation as petrol heads, and the fact that their review was also critical of the impact of EV's on the environment, they've often fell back on the "we're an entertainment show, you're not supposed to take us as experts", when many manufacturers have often said a negative review could cause significant harm in sales.

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[–] [email protected] 28 points 10 months ago (2 children)

Check the results of other cars in this test here: https://outofspecstudios.com/70-mph-range

Yeah ambient temperature dramatically affects the range of EVs. One time I took my Model 3 on a roadtrip and I had quite a bit of range left when I got to the hotel, but the next morning the temperature had plummeted and suddenly I had to make for the nearest charger instead of continuing on for a while. It's just something we have to get used to with EVs I guess.

[–] [email protected] 10 points 10 months ago (5 children)

It's the same with gas, you just didn't notice it as much. Gas cars definitely get way lower mileage in the winter.

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[–] [email protected] 25 points 10 months ago

Musk lied about something? Ooooh no, he's never done that before. /s

[–] [email protected] 22 points 10 months ago (1 children)

People who do business with tesla deserve what they get.

[–] [email protected] 8 points 10 months ago (2 children)
[–] [email protected] 12 points 10 months ago (17 children)

Shoddy build quality and no physical buttons

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[–] [email protected] 18 points 10 months ago (2 children)

Also, the Murdochs are known to fan out the EV bullshit that is being sold these days via their channels.

It's only a matter of time before driving an EV is considered woke.

[–] [email protected] 18 points 10 months ago

It definitely already is and some people will literally buy huge gas sucking trucks that they don't need just to stick it to the libs or whatever

Just throwing away money really but the reasoning is insane

[–] [email protected] 11 points 10 months ago (1 children)

Already there, a conservative I know said to me "it's only matter of time until they make us all drive EVs"

[–] [email protected] 15 points 10 months ago

Which is true, many countries have planned bans on the sale of new ICE cars by 2035. Which is good, even now electric cars are starting to be competitive without subsidies.

I would maybe extra-tax ICEs instead of banning them, so you still have your exotic cars with vroom sounds...

[–] [email protected] 18 points 10 months ago (6 children)

Did the YouTuber run the same type of test that the EPA would run?

I feel like every car I’ve ever owned has had worse milage than what’s on the sticker. But maybe I have a lead foot.

[–] [email protected] 19 points 10 months ago (7 children)

You probably do have a lead foot. I can usually best the sticker mpg especially with hybrids.

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[–] [email protected] 8 points 10 months ago (1 children)

He ran his standard test. Most other EVs in this test exceed the EPA range, most notably he recently tested the EV9 (a literal brick) in similar temperatures.

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[–] [email protected] 13 points 10 months ago

That's honestly way better than I expected. Based on everything else Musk has done recently, and the comedy of errors the Cybertruck has been, I expected 80% less

[–] [email protected] 12 points 10 months ago* (last edited 10 months ago) (10 children)

Wow, just like the cars!

As someone who bought one of their cars the only real positive is that the charging network is available 24 hours a day and very prominent across most of my travel routes.

Additionally, I would say wait out for this industry to get better since every single manufacturer of EV's is full of absolute horse shit in regards to range and safety, ESPECIALLY anything not coming from USA or Europe. Byd's are fucking death traps

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[–] [email protected] 9 points 10 months ago (23 children)

What was the EPA rated highway range? The 320 mile range is the EPA combined city/highway which you won't hit doing entirely highway but you would beat doing entirely city.

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