Which unfortunately also increases tire wear from regen braking during periods when an ICE vehicle would be coasting without braking.
EVs are much (much much) better for CO2, much better for brake dust, and much worse for tire dust.
You don't stay at the zero point. It's an impossibly small target. This is not news to anyone who drives an EV and keeps an eye on the readout showing current power usage/regen.
EVs could coast if a manufacturer chose to make one that allowed that without shifting into neutral. In practice, when letting off the accelerator, existing EVs will instead regen brake.
Modern EVs have easy adjustment for this. The Hyundai/Kia EVs for example have shift style paddles for adjusting this on the fly which includes a mode for regen only when depressing the break pedal.
It's true though that using this mode will extend the life of your tires.
Next time you do this keep an eye on the actual power readout. See if it's actually zero or if it's reporting ~3kW of braking or accelerating.
Whether that is more or less efficient than a zero-power coast followed by some kind of braking exactly at the end... I assume the difference is so tiny that it makes no difference.
How so?
For the purposes of tire wear, applying regen braking in a car is the same as applying brake pads. Generating 5kW of electricity of 10 seconds vs generating 5kW of heat for 10 seconds, same same.
Let's say you're on the highway driving in an EV. You have cruise control on. You go down a hill. The EV's cruise control applies regen braking down the hill, using the tires to slow you to your desired speed.
Let's say you do the same in an ICE vehicle. You will coast down the hill, gathering speed. Cruise control in an ICE vehicle generally will not brake for you. So more of your energy from the hill gets removed as air resistance. When you slow due to air resistance it does not wear the tires.
The same logic applies each time you push the gas pedal slightly harder than you needed to and then back off.
That's an assumption I disagree with. Brake pads will always be less smooth than engine braking. For the same braking action, I assume more brake dust and slightly higher tire wear due to brakes not able to provide fine speed adjustment.
The down-the-hill scenario is interesting, it brings new comparisons: is there more tire wear from maintaining a chosen speed, vs letting the car overspeed and then braking? How does air resistance contribute in each case?
I maintain my earlier opinion that the differences between all these scenarios are minimal and can be ignored. But if you have some physical model that helps calculate these scenarios, it could be fun to play around with.
I'm aware. The point I'm making is that EVs apply more braking than ICE vehicles do, due to the specifics of the implementation of regen braking that all manufacturers have chosen.
> You can coast in EV as well
Not without literally putting it in neutral. If you just take your foot off the accelerator, any modern EV will apply some amount of regenerative braking. It's not really possible to hold the accelerator pedal at the exact position where you are not applying motor power but also have 0kW of regen braking, certainly for any extended period of time.
If your point is that someone could make an EV to which regen braking contributes no more to tire wear than an ICE vehicle, you're correct. Unfortunately, no such EVs are currently manufactured. Even the ones that allow you to "turn off" regen braking will generally apply 1-2kW of regen if your foot is off the accelerator.
Here's a reference for you: https://www.theatlantic.com/technology/archive/2023/07/elect...
But anyway, I find I drive differently with an EV. I don't let off the throttle unless I want to slow down. If I want to coast, I just reduce my throttle input to where its coasting.
Generally they do not allow you to turn it off.
In any case, what's the problem with having it very, very low vs off? Like, what do you really need coasting for? Not something I've felt I've been missing.
My main point is that most people don't turn it off. One pedal driving is convenient!
Hyundai and Kia EVs have a 5 level setting for what happens when you lift up on the accelerator, either partially or fully.
At level 0 the regeneration is so low that I don't notice a difference between that and being in neutral. It slows down way less than an ICE does when not in neutral.
> If you just take your foot off the accelerator, any modern EV will apply some amount of regenerative braking. It's not really possible to hold the accelerator pedal at the exact position where you are not applying motor power but also have 0kW of regen braking, certainly for any extended period of time.
Tire wear is not a linear function of acceleration. Is there any reason to believe that variations from not being able to hold your foot perfectly steady, assuming you aren't have spasms, will be big enough and/or last long enough to make a non-trivial difference?
You can reduce the total braking force needed by extending the time, in which case aerodynamic forces and rolling resistance will contribute some more to the reduction in speed.
In an EV with one-pedal driving you can still stop quickly or slowly. In an ICE car you can stop slowly with more coasting or quickly with more braking force.
I don't see how the drivetrain is going to make a difference to the amount of braking needed to stop and thus force exerted on the tire. The added weight of most EVs would be the larger factor.
Regen is lossy, so there’s no incentive in slowing down to capture 1W just to speed up and spend 1.1W
Porsche has modes for coast and regen. Applying brakes in coast mode will use regen up to a threshold and then use conventional pad/rotor.
So I am sorry to inform you that you’re just wrong.
There are EVs that can coast.
EVs are not braking more.
Whether you use conventional brakes, engine braking, or regen braking, it’s all the same to the tires.
The reason to capture 1W and then spend 1.1W is it keeps you at a consistent speed. That's why manufacturers do it.
Lots of people in these comments who have never actually driven an EV while looking at the energy usage readout.
Personally I've never driven a Porsche but I've driven EVs from Nissan, Tesla, VW, Chevrolet, Kia, and Hyundai and they all do this.
So I am here to inform you that you are just wrong. There's no need to be sorry about educating someone, though, don't apologise next time :-)
The responses tend to be either "actually regen braking wears tires just as much as using brake rotors" by people who didn't actually read, or "surely manufacturers wouldn't do that, it doesn't match the mental model in my head" by people who've never paid close attention to the power readouts while driving an EV.
Your own response was "actually one manufacturer does have a setting that will avoid the effect if someone sets it, therefore the whole concept must be wrong".
In a gas car that means the car is using the brakes and gas engine (obviously) but it’s a jarring experience compared to a BEV or hybrid. The regenerative braking and smooth acceleration are much more pleasant.