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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

#281

Post by ncruces »

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…

And when regenerative breaking is not enough, a series hybrid can still apply compression breaking, before resorting to brakes.

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

#282

Post by mort96 »

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.

I didn't quite get if you think changing gears for the purpose of engine braking wears the clutch more than normal or not. Are you using the force from the clutch to force the engine to go from a low RPM to a high RPM? In cases like that where the difference in RPM is significant, I would press the clutch pedal, then speed up the engine by pressing the gas pedal, downshift, then release the clutch. Rev matching, basically. It does wear the clutch a teeny tiny bit, but not more than any other gear change.

If your comment wasn't meant to imply that engine braking wears the clutch more than normal gearing, if you just want to avoid gear changes as much as possible, disregard this comment. (Although... I'm not sure that that's a valid worry, modern clutches last a LONG time when used properly)

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

#283

Post by lnsru »

brtkwr wrote: post #49
ghushn3 wrote: post #17

Earlier quoted context omitted.

What are you doing to your tires that they only last 10k miles? I think that might be a driver error issue, because my EV (a heavier sedan) basically never needed tire replacement barring me running over a screw or something.

Just normal driving, it wasn’t quite so bad on our previous car which was a Nissan Leaf (with 30kWh battery) but our current Kia Niro just has a lot bigger batter (64kWh) and it is a lot heavier I suppose, the tyres just don’t seem to last as long. I’m pretty sure I’m using summer tyres all year round (I live in the UK) this was recommended by the dealer

I heard Kia Niro has the front wheel drive issue and the tires wear on the front very fast. So you should swap front wheels and rear wheels every year to get best wear result. I drive very poorly and fast, but usually mid-range tires last for at least 30k miles on different cars.

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

#284

Post by jajko »

3eb7988a1663 wrote: post #19
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.

I am just excited because the more EVs mean fewer idiots in hot rods running without mufflers.

Well there are new classes of idiots I see pretty frequently - a typical tesla driver going 90 in 120 region of highway without any reason, presumably saving last bits of battery (that has at least some rationale, if they do it due to ie fear then they should not be driving or having license).

Over say 50km part of highway, maybe 2000 cars need to overtake such almost stationary object (to regular traffic which generally moves exactly at the speed limit). Fine if you have 3+ lanes, but most highways in Europe have 2 only. Then you have all the trucks, buses and rest of traffic trying to overtake via that 1 free lane, which in heavier (but still cca smooth) traffic will create a massive moving traffic jam immediately.

If I didn't see this every other day (and for some reasons its 90% tesla drivers where I live and rest is caravans) I wouldn't believe it to be so common, but it is. Summer now makes it even worse with all holiday drivers.

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

#285

Post by usrusr »

pkolaczk wrote: post #271
cperciva wrote: post #176

Earlier quoted context omitted.

which is the whole point of hybrids Part of the point, not the whole point. Regenerative breaking is absolutely a win; but there can also be a significant benefit from allowing the ICE to remain in the RPM "sweet spot" rather than moving around a larger range.

Another part of the point is that you can pack a much smaller and more efficient ICE and then substitute the missing power and torque from electric motors when needed. Most cars are not used at max power all the time. You need max power only at short times when accelerating. With pure ICE there is the tradeoff - a bigger engine will get you more max power / max torque but is going to be less fuel efficient because of…

On paper, yes, but did that ever happen? Sorry for being sarcastic, but where I live the frugal hybrid is exceptionally rare and the "same big engine, but driving a much heavier car" hybrid is omnipresent. The kind of people who might buy the frugal one buy second or third hand while almost all buyers of factory new pick the "same big engine" option, and those are the ones who decide what's available on the second hand market.

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

#286

Post by mort96 »

labster wrote: post #188
reissbaker wrote: post #130

Earlier quoted context omitted.

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.

It's not like brake dust is white...

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

#287

Post by trained6446 »

ddeck wrote: post #280
ben-schaaf wrote: post #273

Earlier quoted context omitted.

They also use the electric motor(s) for braking, but instead of going into a battery it goes into a bank of resistors.

I think you meant capacitors. Resistors would just dissipate the energy as heat. edit: Thanks for the correction. They do indeed use resistors and just dump the energy as heat. Unfortunate. Hopefully this will change as supercaps continue to improve. Maxwell tech's modules are already used in light rail, and looks like some work towards smaller locomotives in Switzerland here: https://www.osti.gov/etdeweb/servlets/pu…

Nope, resistors. The energy is dumped as heat.

Dynamic brake

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

#288

Post by stavros »

apelapan wrote: post #235
schmookeeg wrote: post #129

Earlier quoted context omitted.

We have owned 4 EVs and each allow you to configure the regen braking strength. You'll need another reason to not buy one.

Tesla is a quite common EV brand. They do not allow configuring regen braking, except for the behaviour at stand-still. (They also don't do blending between friction brakes and regen, so the cars behaviour when letting of the accelerator is highly inconsistent depending on temperature and charge level). One of the reasons I long for the lease on my Model Y to end so I can replace it with a less stupid vehicle.

I agree with the general sentiment, but this isn't relevant in the context of making a purchasing decision. Simply buy another brand.

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

#289

Post by ahartmetz »

ddeck wrote: post #280
ben-schaaf wrote: post #273

Earlier quoted context omitted.

They also use the electric motor(s) for braking, but instead of going into a battery it goes into a bank of resistors.

I think you meant capacitors. Resistors would just dissipate the energy as heat. edit: Thanks for the correction. They do indeed use resistors and just dump the energy as heat. Unfortunate. Hopefully this will change as supercaps continue to improve. Maxwell tech's modules are already used in light rail, and looks like some work towards smaller locomotives in Switzerland here: https://www.osti.gov/etdeweb/servlets/pu…

Capacitors have pitiful energy storage capacity. Resistors is correct, unfortunately.

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

#290

Post by stavros »

Swizec wrote: post #106
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…

> My model Y can effect a very reasonable stop in traffic without touching the brake pedal except to hold the car at the end. My manual car could do this 20 years ago. My fully ICE motorcycle can do it today. I know engine braking is cool but it’s not some amazing new thing only EVs can do. Altho granted it only produces heat and noise in petrol vehicles. But it also makes your heart sing so that’s nice

I have an ICE car and motorcycle, and an EV. The EV slows down much more quickly when slowing down, to the point where it's a good replacement for the brake, as opposed to the ICE vehicles, where you need to use the brake a lot more. It's not comparable.
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