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I am a little afraid of the long-term safety implications of people driving these massive (literally by mass, not volume) EVs. As if being a pedestrian, biker, or small-car driver wasn't already dangerous enough in the US. For context, a compact SUV EV weighs almost as much as many full-size trucks:

Current Cars

* 2023 Compact Gas SUV (RAV4): 3,370 lbs

* 2023 F-150 V8 Supercab: ~4,500 lbs

* Your typical American short school bus: 10,000 lbs

EVs

* 2023 Tesla Model Y: ~4,500 lbs

* 2023 F-150 Lightning Extended Range: ~6,500 lbs

* 2022 Hummer EV: 9,000 lbs

Except now the 9,000 lb SUV can go 0-60 in 3 seconds.




The Hummer in any form seems like a ridiculous vehicle. The Rav4 Prime weighs more than the Model Y, so depends on what version. The 4runner, Tacoma, Tundra, Sequoia etc. are all same or heavier, the big difference is that in the future, battery technology is expected to get better, so EVs should become lighter.

Model Y RWD weighs 4065 pounds, but pretty sure my Tundra is a lot less safe for pedestrians, as it sits higher and weight about 1800 pounds more without fuel.

Yeah, smaller cars are better for pedestrian safety, but North American drivers in general want bigger cars. Ford stopped making passenger cars for NA, even. Although you could argue some of their small 'SUV's are really hatchbacks at this point.

Not sure how you get people to want to buy smaller cars other than taxes.


I should have clarified I'm not picking on the Model Y in particular because I think it's a perfectly reasonably sized car and I agree it's much safer than most full-size trucks, it's just surprising how much EVs can weigh. The worrying trend is that moving forward, there are a lot of EVs much bigger than the model Y in the pipeline:

* Kia EV9 (likely ~6,000 lbs)

* Volvo EX90 (likely 6,000+ lbs)

* Rivian R1S (7,000 lbs)

* Electric Chevy Silverado (likely 8,000+ lbs)

* GMC Sierra EV (likely 8,000+ lbs)


I work on large diesel trucks for a living, and if you told me there would one day be a truck that weighed over four short tons and went as fast as a corvette I'd ask for tickets to your drag race.


Hah, no kidding. It's undoubtedly a massive feat of engineering, but so are a lot of things that don't belong on our roads.

I'd much rather live with the vast majority of smaller cars and trucks electrifying and letting the 0.1% of people who feel the need to drive a Hummer keep their gas-guzzling cars. At least the old gas models were a "mere" 5,000 lbs and accelerated 0-60 in a much more reasonable 7-8 seconds.


I can't speak to the other brands. But per https://www.tesla.com/VehicleSafetyReport, Teslas are averaging about 1/3 the odds of an accident per million miles of other cars. Unfortunately the autopilot figures there are misleading since autopilot only goes on for the safest kinds of driving.

Why? Sensors and maneuverability matter. Being hit by a Tesla may be worse, but it does a lot to avoid hitting you.


not a huge Tesla fan, but they adhere to the road and a breath to drive. The best car for me will still be my grandfather's Xantia (sadly retired now), but compared to tally city car or huge SUVs, a Tesla is rather nice.

I drove a SUV not that long ago on a country road, i now understand why it tends to have more accident than a regular car, especially if you drive fast on a curvy road.


To some degree. It’s also because because Teslas are new cars driven by affluent, youngish people.


One thing to keep in mind is that EVs with single-pedal mode (ie, regen braking always on if not accelerating) are simply way more responsive than any ICE in terms of stopping. They simply brake faster because you simply have to not accelerate.

Faster acceleration also means more confidence so you don't have to keep the momentum.

From a purely anecdotal standpoint, I feel EVs are just safer.


Or, you become so used to using only a single pedal that when an emergency happens you delay using the brake and get into a crash.


We have a nimble EV and a slow lumbering non-EV. Never had this issue and neither has my spouse.


The Hummer is a limited production expensive vehicle. The original Hummer was also extremely heavy :

1995 Hummer H1 6766

2005 Hummer H2 SUT 6780

2006 Hummer H1 Alpha 7558

2009 Hummer H2 6614

-------Stopping distance

2022 Hummer - 70mph 211 ft

2005 Hummer H2 SUT - 70mph 214ft

2008 Hummer H2 - 60mph 152ft (motortrend)

Bringing up the Hummer as an example of EVs makes no sense, they've sold less than 1000 so far. Just in 2022 the F150 sold 653k units. Let's look at weight for the 5 most popular vehicles in the US in 2022.

------- Top 5 Vehicles of 2022 (Car and Drive, Trims excluded so I used the entire range)

1. F150 4000 - 5740

2. Chevy Silverado 4490 - 5240

3. Dodge Ram 4775 - 6439

4. Toyota Rav 4 3370 - 3655

5. Camry 3310 - 3595

Finally, why does weight matter to you so much? Not stopping distance, safety systems, front end design? If I get hit with a vehicle that weighs X pounds and it causes me to die what does it matter if it weighed 2x the amount? Can you show there's a meaningful difference between 3000 pounds, 4000 pounds, and 5000 pounds when you strike someone?

If you are concerned about EV safety because of weight, don't want to restrict non-EV trucks, and used the Hummer EV as an example I believe you are arguing disingenuously.

sources: https://www.caranddriver.com/reviews/a40618071/2022-gmc-humm... https://gmauthority.com/blog/gm/gmc/gmc-hummer-ev/gmc-hummer... https://www.caranddriver.com/reviews/a15131760/hummer-h2-sut... https://www.motortrend.com/reviews/163-0804-2008-hummer-h2/ Weights come from Car and Driver or Google


What’s the argument for mass being a driving factor in pedestrian safety? You’re outweighed substantially by anything bigger than a moped. Certainly anything bigger than a Civic. Seems like it’d be more about body angles, visibility, and driver attentiveness.


Outweighed substantially is doing a lot of handwaving. Turns out that difference matters[1] when it comes to injury.

Maybe an analogous question would be: would you rather be stepped on by a horse or an elephant? Both substantially outweigh you but I bet you'll pick the horse.

[1] https://www.nber.org/digest/nov11/vehicle-weight-and-automot....


If we're talking cars hitting you at 80mph, sure you're probably dead no matter what. But a 9,000 lb car hitting you at 35mph is traveling with the same momentum as a 3,000 lb car going 105mph. You might survive a 3,000 lb car hitting you at 35 mph, you're unlikely to survive the other.


This feels... wrong, somehow - we wouldn't say that a 100,000lb shuttle transporter hitting you at 1mph will do the same damage as your 3,000lb car at 35mph. There's way more dynamics at play here.


It is kind of wrong. What matters is the force impacted upon the person (their acceleration), not momentum. Basically, change in velocity over time is what really matters, but because momentum is conserved, it influences what the total change in velocity is.


You are right I think, it's about impulse, force over time, surface area and how much energy can be transfered through the surface area through the underlying tissue and create a ripple basically. I suspect that at some point, the 'transfer function' of energy just maxes out and mass of the vehicle itself is pointless over that point, as it's all lethal.


I agree. If I jump up and down and impact the earth with my feet it's quite harmless. I suspect above some lower bound it doesn't matter how much something weighs, it's all about how fast something hits you (because it's mostly you that's being accelerated).

Although the weight (and correspondingly, the size) of a car does play into sight lines, maneuverability and how fast the car can decelerate.


If you're at a crosswalk, then you'll roll over the hood of a Camry or Mustang going 30mph.

If the same thing happens with a Escalade or F150, there's more mass and it's hitting dead on.


Bumper height is the factor there, not weight. A higher bumper is more likely to knock you down and under, not up and over.


Brake distance, the heavier the vehicle the longer it takes to slow it down.


I'm surprised I'm not finding a weight vs. stopping distance graph anywhere. I know that the physics theory says weight doesn't matter for stopping distance (spherical cow in a vacuum), but there's some nonlinearity in the friction response that does make it matter somewhat. It'd be interesting to know how big a different it does make.


Would you be satisfied to address your safety concerns by: 1. banning cars from regions with a high density of pedestrians (e.g., like downtown London) 2. requiring dedicated bicycle lanes at mid-density regions 3. recognizing that pedestrians and bikers don't really exist appreciable number in rural regions and leave those areas alone?


> massive (literally by mass, not volume)

As a Gen-Xer I used borrow my parents' minivan quite often when I was young, and I could easily/regularly fit 6-7 people in that comfortably. For all their size, a lot the SUVs nowadays cannot accomplish that.

Why are these SUVs so big? What is their size going towards?


Suspension, leg room, boot space and also safety the Minivan that you used to borrow in the 90’s was built quite differently.


A minivan is still more practical. They’re just not “cool”.


There's no physical law of nature that requires EVs to be heavier than ICE equivalents.

As battery tech improves they'll get lighter and they're predicted to beat ICE on this metric in a couple of years


Battery energy density reaching that of petrol in a couple of years is unlikely to nigh impossible unless you’ll be switching to hydrogen fuel cells and even then I’m not entirely sure about that due to the energy density per unit of volume being drastically lower.


"long term", EVs are going to be significantly lighter than modern gas cars because the batteries will continue to shrink. An electric drivetrain is much lighter than an ICE drivetrain.


I think they'll probably end up around parity. Energy density will improve, but people are still likely to want to have a big enough battery that range isn't an issue.

One thing I think that could dramatically improve people's perceived need for energy storage capacity is if we started getting electrified roads where cars and trucks can charge while moving. (There are some of these in Sweden and Germany as test projects, and apparently Sweden is moving forward on doing a permanent installation.)




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