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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

#261

Post by Asmod4n »

jnpnj wrote: post #227
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.

I heard about that long ago but couldn't find more, so IIUC chemically it's easier and more efficient to have a "one mode" combustion engine and let the electric engine deal with the variations, to the point that the reaction produces near no toxic byproducts, is that right ? I was wondering if there was research to keep improving that part. Even though it would help sustain the fossil fuel industry..

Nissan hat the e-POWER system where a petrol engine is just used to recharge the battery of your electric car and nothing else. In theory they could run that petrol engine at the sweet spot where it produces the least amount of carbon emissions.

i believe there is also a chinese company which is making such a car, their cars have nearly 1000 miles range.

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

#262

Post by jve »

beau_g wrote: post #221
dotancohen wrote: post #203

Earlier quoted context omitted.

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've seen an interesting A-B test with this seeing the difference in clutch wear between the Ferrari F1 transmission in the 599 and 612 and the DuoSelect transmission which is essentially the same box in the Quattroporte. The shifting strategy and technique is more of a controlled variable here because the shifting is automatic though it's a somewhat traditional manual gearbox with hydraulic actuation. The QP is a bi…

Sorry, ain't native: Which car use downshifting to help braking? Cannot wire in my brains whether this example is pro-downshift braking or not.

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

#263

Post by p0w3n3d »

jnpnj wrote: post #227
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.

I heard about that long ago but couldn't find more, so IIUC chemically it's easier and more efficient to have a "one mode" combustion engine and let the electric engine deal with the variations, to the point that the reaction produces near no toxic byproducts, is that right ? I was wondering if there was research to keep improving that part. Even though it would help sustain the fossil fuel industry..

AFAIK this is about engine efficiency. ICEs have highest momentum and efficiency sweet spot somewhere in the middle of available revs, which depends on the engine construction and was being altered by different mechanisms (like turbocharging and variable valve timing) but since the electric engine (I'm speaking of Toyota solution) is able to keep the ICE in the sweet spot with its eCVT, the engine can be simplified and even work on different combustion cycle (Atkinson's cycle)

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

#264

Post by masklinn »

cperciva wrote: post #176
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...

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.

Afaik that’s pure series hybrid and that’s almost non-existent in cars (outside of range extenders, not that there are that many of those).

There are a handful but most hybrids are either parallel or series-parallel. I assume because the power range is so low that the conversion losses are way too noticeable compared to a mechanical drivetrain.

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

#265

Post by federiconafria »

masklinn wrote: post #264
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.

Afaik that’s pure series hybrid and that’s almost non-existent in cars (outside of range extenders, not that there are that many of those). There are a handful but most hybrids are either parallel or series-parallel. I assume because the power range is so low that the conversion losses are way too noticeable compared to a mechanical drivetrain.

That's something I wish there had been more focus on, instead of focusing on massive heavy batteries, develop the hybrids further.

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

#266

Post by Toutouxc »

SV_BubbleTime wrote: post #246
Toutouxc wrote: post #112

Earlier quoted context omitted.

More like 20 minutes, but ok, not everyone likes that.

20 minutes to get you home if there is a free charger, ok. Zero to a hundred, you know that isn’t even remotely true.

My cheap EV gets 200+ km of range (124 mi) from 20 minutes of charging. Again, why the hell are you talking about two hours. Why are you saying that 20 minutes gets you "home". Why are you talking about charging from 0 to 100 % when that's NOT how you charge an EV, ever. Sounds like you've never driven one.

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

#267

Post by masklinn »

jve wrote: post #262
beau_g wrote: post #221

Earlier quoted context omitted.

I've seen an interesting A-B test with this seeing the difference in clutch wear between the Ferrari F1 transmission in the 599 and 612 and the DuoSelect transmission which is essentially the same box in the Quattroporte. The shifting strategy and technique is more of a controlled variable here because the shifting is automatic though it's a somewhat traditional manual gearbox with hydraulic actuation. The QP is a bi…

Sorry, ain't native: Which car use downshifting to help braking? Cannot wire in my brains whether this example is pro-downshift braking or not.

I think their point is that you eat clutch when you slip it e.g. when you’re getting in and out if parking on hills, or in city stop and go traffic. When the clutch is fully engaged there’s little wear even hard-driving, and doing a straight in-and-out does not bother clutches much.

Hence Quattroportes eating clutches like nobody’s business while the harder-ridden higher-power Ferraris don’t.

As such downshifting would not wear clutches much.

And anecdotally I’ve never suffered from or heard of engine braking causing clutch issues.

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

#268

Post by Peanuts99 »

tbrownaw wrote: post #185
djrj477dhsnv wrote: post #156

Earlier quoted context omitted.

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.

I use one peddle driving all the time and manage to keep a steady speed as I'm doing it. Why would you be constantly taking your foot off the accelerator unless you need to slow down?

I'll also throw another anecdote in for this thread, 500hp EV, 50k miles on the tyres.

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

#269

Post by pkolaczk »

masklinn wrote: post #264
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.

Afaik that’s pure series hybrid and that’s almost non-existent in cars (outside of range extenders, not that there are that many of those). There are a handful but most hybrids are either parallel or series-parallel. I assume because the power range is so low that the conversion losses are way too noticeable compared to a mechanical drivetrain.

But series-parallel has the very same advantage - can keep the RPM in sweet spot.

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

#270

Post by jajko »

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!).

That's not OK by any means, you don't have mandatory periodical technical inspections? This would fail immediately in any half-decent country. An example - wife's older Seat has 6 years old winter tires which were given for free when buying it second hand a year ago. Technician just told us even those are beyond acceptable here in Switzerland and we need to change them before next inspection.

Your very old tires makes you a serious threat on the road while completely oblivious about this fact... not cool, please change them if you drive on public roads, if not for you just for the sake of others.

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