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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

#661

Post by jjfoooo4 »

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.

Is that not what "Chill Mode" is? I've activated that on my car to relieve some of the jerkiness and it seems to have worked well

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

#662

Post by thijson »

theshrike79 wrote: post #398
throw0101d wrote: post #363

Earlier quoted context omitted.

> […] 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. Which is why I'm surprised electric cars with range extenders aren't a bigger thing: * https://en.wikipedia.org/wiki/Range_extender Have the powertrain be all-electric, and have a battery pack, but for those with range anxiety have a small generator as an option that woul…

Diesel REX vans would be a MASSIVE hit if a company would just decide to start making them. The #1 reason for (european) companies not buying full EV vans is range, they need to drive a LOT during the day. REX would solve that with minimal emissions. And depending on the battery size, they could drive on full EV in city centres and only allow the REX to charge the battery during longer drives. The BMW i3 REX is a fan…

They are the cheapest hybrid out there currently, at least here in the USA. I think the average American prefers a larger vehicle.

I think a Diesel indirect injection REX would be awesome. It could burn vegetable oil, which is more viscous, but indirect injection doesn't need to atomize the fuel as much.

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

#663

Post by frollogaston »

frollogaston wrote: post #574
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…

I semi-daily drive a DuoSelect Quattroporte, but usually in light traffic. The clutch-eating problem is sorta inherent to the car. First off, it uses extra clutch to smooth out shifts in non-sport mode, and you don't always want sport mode because it stiffens the suspension a lot. But even in sport, you can't always get it to behave predictably. So given an experienced driver with both cars in city traffic, the DuoSe…

Forgot to clarify, there is a clutch-eating problem when driving the car properly, but it's not THE clutch-eating problem people talk about where it dies in 10-15K miles from treating the car as a regular automatic.

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

#665

Post by taeric »

klaff wrote: post #652
taeric wrote: post #637

Earlier quoted context omitted.

My understanding is that the overall system is more efficient. It is only the transmission that is less so. The videos online that look at various CVT systems is truly an amazing resource that I regret not having when I was younger. :D

If overall efficiency is what you see reflected in the EPA mileage numbers (or similar European tests), in what scenario would a lower efficiency transmission (lower Pout/Pin over some range of operating points?) lead to or even allow better overall efficiency?

I'm not sure I understand the question? You get the engine to hit its sweet spot and to hold it there. That gain outweighs the loss from the new transmission.

This would be similar to hitting the optimal torque point. The idea there would be that you can get out of the acceleration phase faster, so that you can transition to a more efficient gear to maintain the speed for longer.

The wikipedia looks to cover this well. One of the cites is specific on the efficiency of the CVT. I think I overstated how much higher the loss is, so maybe that is confusing things? I thought it was 10-20, but the cite on the page shows it solidly around 10.

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

#666

Post by HPsquared »

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.

Diesel engines with all their turbochargers, EGR, SCR, DPF etc equipment, work pretty well as part of a hybrid system. All that stuff works much better in steady-state operation. Diesel hybrid buses and trucks are much smoother and cleaner than non-hybrid.

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

#667

Post by tim333 »

MetaWhirledPeas wrote: post #509

It feels like we are still trying to convince ourselves that EVs are a good idea. Progress is too slow and too painful.

There are some technical issues in terms of changing over in a hurry due to providing charging infrastructure and the like.

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

#668

Post by 1234letshaveatw »

sofixa wrote: post #621
1234letshaveatw wrote: post #552

Earlier quoted context omitted.

It's really not hard to share a cell phone, you and eg your spouse could alternate days and have one phone for example. It is just a tradeoff you are not willing to make. But, not having a car is a tradeoff YOU are willing to make so your are ok with pushing it on others.

> But, not having a car is a tradeoff YOU are willing to make so your are ok with pushing it on others. Nobody is trying to take your car away, you scared person who cannot fathom not being attached to a car. I'm merely saying there must be alternatives to driving. I don't care what they are, they will be location dependent. If you want to drive, as long as you pay your externalities, nobody cares. But it's fundament…

Don't be afraid piglet, I won't take your phone. Nobody is trying to outlaw public transport- but there absolutely people advocating for an end to private ownership of cars

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

#669

Post by Swizec »

yreg wrote: post #244
Swizec wrote: post #106

Earlier quoted context omitted.

> 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

And how often did you engine break with that ICE car when driving around the city? Because I did it only when driving down extreme slopes. It also cannot do a full stop. With an EV I don't touch breaks unless in situations I fail to/couldn't predict (maybe up to 10% of all speed reductions and even less stops).

> And how often did you engine break with that ICE car when driving around the city?

Oh all the time. I used to drive like a typical youth. I've been in USA for 10 years now and still hate driving automatics because they shift into too high a gear and then you have to constantly use the brakes. It's annoying.

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

#670

Post by buerkle »

OkayPhysicist wrote: post #656
whycome wrote: post #588

Earlier quoted context omitted.

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.

My Bolt has a hand paddle behind the steering wheel that engages regenerative brakes (and only the regenerative brakes). I make use of it extensively. When in "single pedal" (where the accelerator acts as a speed selector, i.e., the car brakes when you step off the 'gas'), it's a lot more aggressive than just lifting my foot off the pedal, and when in "simulate an automatic transmission" 2 pedal mode, I find the padd…

I love my bolt, but I wish it allowed you to choose a less aggressive setting when using the steering wheel paddle. My old leaf had that option.
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