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Comment by ceejayoz | Hacker News Reader

EVs make substantially less of that, due to regenerative braking.

What portion of drivers use one pedal?

You don't need to have the one pedal driving enabled to reap the benefits. In all EVs and PHEVs you brake with the electric motors first even when using the actual pedal - normal brakes are engaged only past a certain threshold.

Also to give a personal anecdote, in my Volvo XC60 PHEV, I've just had the inspection done and after 24k miles the brake pads are 5% worn. That's insane for a 2.2 tonne SUV with 400bhp. If it wasn't a PHEV I can guarantee that the pads would be nearly worn by now.

While EVs do use less brakes than ICE, they still should last a lot longer than you give them credit for.

Of course it's depends on how you drive, but if you are not getting 100k miles out of your brakes the problem is not the car but the driver.

Sure. My last car was a Mercedes AMG that needed new pads every 8-10k miles, so I might be a bit biased. But TBF my car before that was a Land Rover Discovery 3 and that was eating pads like crazy despite not driving it aggressively at all - I attributed it to the weight of the vehicle.

> if you are not getting 100k miles out of your brakes the problem is not the car but the driver.

This is just false. If you get 100k in your non-EV before having to replace at least your front brake pads, you must be racking up highway miles.

You are very out of date, on a modern car the rear brakes will go first. With traction control they move all the braking to the back, if possible, so steering works better. Of course if you brake hard there is no choice but let the front brakes take over, see my comment about bad driving.

> you brake with the electric motors first

This is not true. At least for Teslas, the brake pedal only controls the friction brakes (they are hydraulically coupled). Same with a Chevy bolt. Unsure on other EVs

Yes, Tesla is an outlier in the EV business. They only have one-pedal driving with regen or fully friction braking with the brake pedal. That is not true of the Chevy Bolt.

Almost every other EV (and hybrid) on the market does blended regen with the brake pedal. Regen is applied when you first press on the brake pedal. As long as the pressure is mild to moderate, regen is used. If you press hard (as in emergency braking) the friction brakes are engaged. When you get below about 10mph the friction brakes are also applied as regen is minimal at that speed. The result is that these cars will do regen whether you are using one pedal driving or not and their brakes will wear much less often.

I’m not sure why Tesla doesn’t do blended regen. Early one the manufacturers didn’t have the algorithms tuned and you could feel the transitions but that has not been the case for several year. It seems that Tesla just never bothered. They seem to expect you to only use one-pedal driving and some people do.

One think to watch for if you only use one-pedal driving, your friction brake pads can get rusty from disuse. Then when you do press on the brake pedal, the brakes may grab or may not decelerate as quickly as expected. Some people find that their brake pads are actually frozen from rust and don’t work at all. It is a good idea to once in a while use those friction brakes to scrub off the surface rust.

Well regenerative braking is limited and even more limited when cool. So Tesla's trying to train you to use the brake pedal when you want stronger braking. Makes sense to me, last thing I want is to get half as much braking as I expected.

So with regen I get variable braking, but I get a reward (more range and less brake wear) if I plan ahead enough to make it work. However if there is surprise or immediate need for more braking then the brake pedal is there. So it's pretty much the best of both worlds, once you get used to it.

In a well designed system you have absolutely no idea whether the car is using the regenerative brake or proper brakes when you use the pedal - my Volvo XC60 uses regerative brakes first and you honestly can't tell when the transition happens. There is no "oh shit I need more braking" moment because the pedal operates in a very predictable linear fashion, like in any normal car. Same in my VW e-UP. The algorithms for this have been sorted out for a while now.

So sure, it feels great and provide predictable braking. But is harder to maximize range and minimize brake wear and brake dust.

I generally drive only using regen, because I can tell. If you remove the feedback it's going to be harder, especially since the level of regen available can radically differ based on temperature and level of charge.

So do you want regen to be invisible? Or do you want better range, efficiency, and brake wear?

In my XC60 the dial just goes below zero when you're breaking into regen zone, and then there is a little red area at the end of it - if you get into the red zone, normal brakes are used. So there is feedback, you just don't feel it through the pedal.

It looks like this:

https://www.swedespeed.com/cdn-cgi/image/format=auto,onerror...

Non-Tesla’s also give you “the best of both worlds” by having regen on both the accelerator lift-off and on the bake pedal. Tesla only gives you regen on lift-off.

Not so sure. On other cars say you want to maximize your range and minimize brake wear/dust. How do you drive?

On a Tesla you just lift the throttle, and if that's not enough you are aware of it, and change your driving patterns accordingly.

With a mixed setup, how do you know when and how much the brakes are involved? Doubly so when it's too cold, or the battery is too full for regen.

In Teslas, any time your foot is completely off the accelerator, you're getting maximum regenerative braking. If you then press the brake pedal too, you're getting maximum regenerative braking plus friction braking.

I think I misunderstood your use of "actual pedal" in the GP comment. You meant accelerator by that? I assumed brake pedal

My point was that unless you do something bizarre or go out of your way to make regeneration not happen (e.g., hit both pedals at once, or shift into neutral while braking), the friction brakes will never get used except for when full regen is already getting used.

Teslas don’t use regen on the brake pedal. That is only using the friction brakes.

Right, but they use regen just by releasing the accelerator. So unless you're hitting both pedals at once, you will be regenerating every time you're braking.

Does the one-pedal regen continue to operate when you are pressing on the brake pedal?

Yes.

If you use both pedals at once it will reduce acceleration and warn you.

I assume most Tesla drivers, at least, it’s definitely the happy path. I probably use my brake pedal once every few hundred miles.

The EPA uses whatever the default settings for the car are, so it's usually on my default. Anecdotally most people I know use it

Most EV drivers, I’d say. My sample size is small, but me and my friends who have EVs all drive with one pedal.

Are there EV drivers that do not? I don’t think I could ever go back to using 2 or 3 pedals.

I only use one pedal in stop and go or city driving. Otherwise it's harder to maintain smooth speeds and is less efficient than just coasting.

Cruise control should solve that problem no?

Most of them as far as I can tell. It’s one of the main buying points to getting an EV.

My Model S is approaching 90k miles and I have not needed to replace the pads. It has two pedals.

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