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Electric cars produce less brake dust pollution than combustion-engine cars

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Re: Electric cars produce less brake dust pollution than combustion-engine cars

#581

Post by masklinn »

pkolaczk wrote: post #274
fho wrote: post #184

Earlier quoted context omitted.

The rear brake rotors on my Yaris hybrid are basically always rusty because they get used so little. After some time you just know when to start braking so you only use regen instead of the brakes.

I confirm and that’s an unpleasant surprise. Already had to replace the rear rotors and pads on my Highlander… because of rust. They should add some “brake cleaning” mode to temporarily disable regenerative braking.

Also forget about that bit:

> They should add some “brake cleaning” mode to temporarily disable regenerative braking.

Some manufacturers do that (iirc tesla calls it burninshing, others will switch regen off completely if you switch to neutral or something).

I've read that Audi and Porsche will use regular brakes once or twice at the start of every drive instead of regen, I assume using electronic control to imitate the current state of regen braking.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#582

Post by masklinn »

dboreham wrote: post #477
chakintosh wrote: post #385

Earlier quoted context omitted.

On both my Volvo PHEVs I often look at the brake discs and find them rusty from the amount of regen braking. it almost completely eliminates conventional braking unless it's for collision avoidance.

My EV turns regenerative braking off for the first use of brakes after beginning a journey, to avoid the rusting disc syndrome.

What car brand is it? I've read that Audi and Porsche do that.

Also is it only pedal braking? Or does it "fake" things out if you use one-pedal driving?

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#583

Post by tonymet »

nordsieck wrote: post #567

From what I've heard there's a countervailing effect for EVs, though - they end up generating more particulate pollution from tire wear because of greater vehicle weight and greater torque. The number that I've seen bandied about is ~20% greater tire wear.

They address this briefly in the article (though inadequately) , that tire particles are heavier and doesn’t end up in the air like brake dust.

But you do raise a good point at the holistic condition, and assessing a broader population with less than ideal configuration.

They are looking at lightweight EVs at lower speeds. But Americans drive heavier EVs at highway speeds. The rotors & pads are huge.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#584

Post by analog31 »

tonymet wrote: post #580

You can get similar results with proper deceleration, engine braking and downshifting. I’ve had brake pads last 110k miles (with room for 20k+ more), even though I lived in moderate hilly area. That’s probably 1/3 the brake dust, and comparable to an EV . If you are getting lower MPG than the EPA rating, you are also burning up your brakes from heavy deceleration. Improve your MPG to 15% over EPA and your brakes will…

Upvoted for making sense of basic physics.

Another factor is speed.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#585

Post by [deleted] »

arnonejoe wrote: post #123
ajross wrote: post #88

Earlier quoted context omitted.

To some extent, but not really. Effectiveness of regenerative braking depends on having an extremely large battery that can sink enough current to stop the car. An EV can do that, hybrids at best help the brakes out some. You just can't charge the battery fast enough doing anything but a very slow rolling stop. My model Y can effect a very reasonable stop in traffic without touching the brake pedal except to hold the…

I test drove an EV and the regenerative braking was difficult to get used to. You have to constantly ride the gas pedal. I would buy an EV if it weren't for this feature.

[deleted]

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#586

Post by eulers_secret »

pinko wrote: post #516
nixass wrote: post #508

Earlier quoted context omitted.

That's the case only with CVT transmission

Are there still a lot of hybrids without CVTs?

Hyundai/Kia use a traditional 6-speed auto in their hybrids. I drive one, the engine stays at a few RPM stepping points during most driving (it likes ~1600RPM, ~2200RPM, and ~3600RPM). I had a Prius previously, and I like this different setup because it reduces "engine droning noise", which was terrible on the Prius.

Though H/K have recently introduced a new hybrid system with a CVT, so maybe 2026 or 27 model years will be different.

Since I'm only making one comment, I also want to say hybrid cars are better than ICE because there are fewer belt-driven accessories. Aircon in particular on an electric motor is a big improvement. Without the idling engine producing heat, hybrids are much nicer in hot stop-and-go conditions!

Also my Prius made it its whole life (200k miles and ~20 years) without ever changing the brake pads... amazing!

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#587

Post by NwtnsMthd »

dotancohen wrote: post #203
MindSpunk wrote: post #154

Earlier quoted context omitted.

You don't engine brake with the clutch, you engine brake by downshifting and using the higher engine RPM in lower gears to brake the car via wasted compression.

And that downshifting involves a clutch operation, moving the engine into a higher RPM. That most certainly wears down the clutch, talking as someone who's replaced quite a few of them.

It's a negligible amount, especially if you (or your car) does rev matching. My last car (BMW 328) made it to 300k miles on the original clutch.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#588

Post by whycome »

janosch_123 wrote: post #540

For DIY EV conversions (I built some cars) you usually hook up the "regenerate braking" to the brakelight switch. So as soon as you tap the brake pedal just a little, you start regenerating and see the amps flow back into the battery (I have a little display on my dashboard). Only when you press the pedal further, do you start engaging the friction brakes. I have no statistics on brake pad differences because we didn…

With a manual car, it was common to downshift and use the engine to decelerate. I’m wondering if electric vehicles might actually cause a return to a third pedal to re-add some of the fine tuned controls that a manual transmission allowed. Maybe the “downshift” could engage the regen brake specifically.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#589

Post by SoftTalker »

tonymet wrote: post #580

You can get similar results with proper deceleration, engine braking and downshifting. I’ve had brake pads last 110k miles (with room for 20k+ more), even though I lived in moderate hilly area. That’s probably 1/3 the brake dust, and comparable to an EV . If you are getting lower MPG than the EPA rating, you are also burning up your brakes from heavy deceleration. Improve your MPG to 15% over EPA and your brakes will…

But in a manual transmission car, downshifting and engine braking produces clutch dust instead of brake dust (basically the same thing).

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#590

Post by ceejayoz »

sofixa wrote: post #521
1234letshaveatw wrote: post #488

Earlier quoted context omitted.

I'm sure you feel the same way about cutting down on cell phones right? How about we just let people keep their cars (preferably EVs), but feel free to go live in a dense cell block and eat bug juice if that is what floats your boat.

> I'm sure you feel the same way about cutting down on cell phones right How many people die in cell phone accidents yearly where you live? How many have reduced lifespans due to the pollution of cell phones? And how many hours can be saved per year per human with good cell phone sharing? I would guess the number is 0 for all of those, but quite a bit higher for cars alternative transportation options. If you feel pe…

> How many people die in cell phone accidents yearly where you live?

To be fair: thousands. https://www.ncsl.org/transportation/distracted-driving-cellp...

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