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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

#181

Post by CraigJPerry »

tbrownaw wrote: post #136
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…

> 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. This seems a bit exaggerated. Staying regenerative-only does require sticking to about half or so of how fast I could stop, but so far th…

100% of possible system capacity to accept regenerative charge on a smaller battery system will be a smaller absolute number than 100% of possible on a larger battery. If you assume everything else is constant, motor, inverter, battery C-rating etc.

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

#182

Post by cyberax »

altairprime wrote: post #39
rayiner wrote: post #16

We should obviously ban combustion engine cars, at least starting with cities. I can’t think of a single clearer win for air quality.

If all of us renters were forced to convert to electric there’d never be an open charger in any city again for the next five years, because no landlord will voluntarily afford that cost, and no municipal region can pass a ballot measure to afford that cost. California’s impending ban of combustion car sales hinges wholly on a magical DC-charging network that doesn’t exist in U.S. cities yet (i.e. at parking meters),…

> If all of us renters were forced to convert to electric there’d never be an open charger in any city again for the next five years, because no landlord will voluntarily afford that cost, and no municipal region can pass a ballot measure to afford that cost.

Landlords can charge tenants over the price of electricity.

> What city has charging available for an average of greater than one spot per five hundred multifamily-housing residents?

Shanghai: https://english.shanghai.gov.cn/en-Latest-WhatsNew/20240508/...

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

#183

Post by avidiax »

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.

> you have to constantly ride the gas pedal.

Are you not? Do you drive by blipping the gas every few seconds?

I've had Uber drivers do this and it is annoying bordering on nauseating as a passenger. It is probably pretty bad for mileage and transmission wear as well (constantly taking up and releasing the backlash in the gears).

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

#184

Post by fho »

nine_k wrote: post #41

I suppose the same should apply to hybrid cars, which outnumber pure EVs significantly [1]. The effect comes from converting the kinetic energy back to the battery charge via generation instead of wasting it via friction, which is the whole point of hybrids. [1]: https://www.consumeraffairs.com/automotive/how-many-electric...

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.

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

#185

Post by tbrownaw »

djrj477dhsnv wrote: post #156
slt2021 wrote: post #146

Earlier quoted context omitted.

the level of regenerative braking directly impacts your accelerator pedal behavior. by reducing regeneration, you will increase tire life by virtue of modifying your acceleration behavior. Its hard for me to explain, but I just suggest trying the medium regenerative setting and you will see it yourself. You will feel it, because the most of the tire wear happens when car decelerates. On less regeneration your car wil…

That's a whole lot of assumptions based on what? I could come up with a list of plausible sounding reasons why regenerative braking leads to less tire wear. Unless you have some actual measurements, I wouldn't trust either one.

I'm reading it as referring to a setting where the car will brake some amount (instead of coasting) if you completely let go of the pedals, and as being a claim that the commenter can't maintain speed but gets stuck in a cycle of accelerating and then letting the car brake.

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

#186

Post by MindSpunk »

cloverich wrote: post #153
frollogaston wrote: post #80

Earlier quoted context omitted.

And manual transmission cars kinda, though the energy is still wasted of course

Surprisingly you can get nearly same effect in automatics. I put around 60k miles on my first automatic (after120k+ on my first two cars, manual transmissions) and when i got my brakes checked at 63k they noted my brakes were still "brand new". I do gamify reading traffic to try and brake as little as possible (to help pass time etc), but was still surprised how far this takes you given i do plenty of stop and go tra…

It's not "nearly". It's exactly the same effect. Compression braking. Even if you're not on the throttle the engine is still rotating as it's connected to the wheels. If the engine is rotating it is compressing air. If it's compressing air but not igniting fuel (throttle closed) then it will suck energy out of the wheels to compress the air.

You can do it in an automatic, you just have to force it to select a lower gear using the gear number options (1, 2, 3, 4) or using the tiptronic mode. The lower gear means the engine will displace more air in the same amount of time, increasing the rate it pulls energy from the wheels.

People think you can't do it in automatics because they try very hard to keep engine RPM low where the effect is diminished.

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

#187

Post by dontlaugh »

mjevans wrote: post #142

Ban the stop and go hell of rush hour. Cars rolling at freeway speed without stopping pollute way less than drivers stuck behind idiots who can't just go forward down the road at the speed limit. The human suffering and ecological impact reduced if only there would be a focus on enforcing speed minimums...

I assume by that you mean provide good and cheap public transportation so people no longer have to drive.

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

#188

Post by labster »

reissbaker wrote: post #130
brtkwr wrote: post #4

An an EV owner, I can testify that the tyre wear more than makes up for the reduction in brake dust. I’ve had to change tyres every 10K miles.

The article says that even including tire and road wear, EVs generate 38% less particulate pollution than ICE cars before considering the lack of tailpipe emissions.

But tires are black, and black carbon has additional climate effects — even once the aerosol lands, it can still have effects like black carbon on snow.

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

#189

Post by eptcyka »

teleforce wrote: post #141
stephen_g wrote: post #5

Good to have more data points and evidence, but this seems extremely well established by now? Zero tailpipe emissions, drastically removed brake dust, slightly higher tire wear (due to weight), but much better overall than ICE.

>drastically removed brake dust It will be very interesting to see the data for the same car that has many powertrain versions for example the Lexus UX with the UX 200 (ICE), UX 300h (hybrid) and UX 300e (EV) to test which one the best and the worst in term of brake dust residue. My hypotheses is that for brake dust residue the best is hybrid, 2nd will be ICE and the 3rd will be EV. This is due to the fact that the E…

Yea, but the EV need not use the disc brakes to stoppe.

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

#190

Post by Tempest1981 »

Helmut10001 wrote: post #124
dyselon wrote: post #99

Earlier quoted context omitted.

We finally gave up our Prius after 12 years, and we never changed the brakes once. The brakes were just peeking into the yellow on its last service upgrade. I was really impressed with how well the "normal" hybrid could take advantage of regenerative breaking, honestly.

I first changed the brakes on my Mitsubishi Space Star (combustion) after 13 years. It is a small car, less than 1000kg, so there is little for the brakes to do. If we produced more percentage of small cars, many environmental risks would be reduced. And btw.: The tires are now 19 years old and still good (less weight, less abrasion!).

Rubber degrades with UV exposure, even if the tread depth is ok. Be careful, esp at higher speeds.
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