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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

#721

Post by relaxing »

madaxe_again wrote: post #250
relaxing wrote: post #23

Earlier quoted context omitted.

EV owners aren’t exactly rare around these parts. Neither are people who drive cars of a similar weight, such as midsize SUVs. There’s no good reason why you should be changing your tires at 10k miles.

When you can see interleave that’s a good reason to change your tyres. My stock tyres on a model Y lasted 11,000km - but my daily drive is a tortured ribbon of tarmac with nothing but corners.

I don’t know what interleave means in your country but the way to measure tire wear is replace when tread depth gets below 1.6 mm.

Next time get tires with a 50k mile warranty, like Pirelli Scorpions.

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

#722

Post by taeric »

klaff wrote: post #716
taeric wrote: post #665

Earlier quoted context omitted.

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 wel…

Ah, thank you, I see the argument. I'm still a bit skeptical though when many non-CVT automatics are 6 or 8-speed models that there would be much "sweet spot" benefit left by being able to make relatively small changes in engine speed. Like many things probably depends on exactly what comparison is being made.

I mean, we are comparing 6-8 to effectively infinite? Question then comes into just how much is lost by being outside of the sweet spot for an engine. Which, I agree that I would not have thought it would be that big of a deal. Just going off modestly paying attention in my car, I see massive benefits keeping the car around 300 rpms lower.

Interestingly, my car gets better gas mileage around the 40ish speeds than I do at full highway speeds. That somewhat surprises me. It is very dependent on not having a heavy foot, of course.

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

#723

Post by dotancohen »

polairscience wrote: post #657
dotancohen wrote: post #649

> The health effect is especially critical for urban disadvantaged groups, where exposure to partical matter has been shown to be related to increased asthma rates, cardiovascular disease, and other respiratory conditions. Why would the health effect be more critical for disadvantaged groups than for other urban groups?

Sincere reply assuming sincere question, the implication is that they are statistically much more likely to live near interstates and highways. Since historically land owned by poor 'disadvantaged groups' has been easier for state and federal governments to get their hands on. The sentence, while poorly written, isn't saying that "health impacts don't matter for 'non-disadvantaged people'". A reading that is disingen…

I see. In the areas familiar to the authors, disadvantaged groups typically live closer to the source of the pollution.

Makes sense now. Thanks.

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

#724

Post by jdsleppy »

dotancohen wrote: post #649

> The health effect is especially critical for urban disadvantaged groups, where exposure to partical matter has been shown to be related to increased asthma rates, cardiovascular disease, and other respiratory conditions. Why would the health effect be more critical for disadvantaged groups than for other urban groups?

Also disadvantaged groups might consume less healthcare and might be less aware of air quality, etc. and so may be more likely to have bad health outcomes for given environmental inputs.

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

#725

Post by BHSPitMonkey »

SV_BubbleTime wrote: post #611
Toutouxc wrote: post #494

Earlier quoted context omitted.

Dude, literally every single EV-related number you’ve mentioned around here is so insanely off. Two hours at a charger, 20 minutes of charge just to get home, charging an EV 0 to 100 % and now again, charging a 60 kW battery every day. I don’t know what kind of terrible EVs you’ve seen, but they weren’t what normal people drive. Either get some real world experience with EVs or just stop posting about them.

Interesting… so, for reference I’m an automotive engineer and have worked one at least three EV platforms for big4. Good to know how wrong I am on this topic. Let me guess, you own an EV? Well, that certain explains it everything.

You received some better corrections in earlier replies, which you've chosen to ignore... That's your prerogative of course, but there's no need to resort to "I'll have you know I graduated top of my class in the Navy Seals"-style reverse ad hominem to make an argument.

You made some basic mistakes in your previous reply, such as confusing power (kW) and energy (kWh) and assuming that a typical driver in HI commutes something like 250mi each day. This isn't even typical for drivers on the mainland, where plenty of EV+solar owners manage to replenish most or all of their EV usage using rooftop solar generation just fine.

(If you're going to answer "well, I never said I was considering the median distance/day case - I was talking about the most extreme scenarios!" then I'd suggest at least bumping up the hypothetical solar installation to 10kW instead of going with the median.)

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

#726

Post by mnw21cam »

morkalork wrote: post #688
mnw21cam wrote: post #644

Earlier quoted context omitted.

If you drive down any significant hill, you either use engine braking, or you overheat your brakes. It's a fairly basic part of driving tuition and the driving test for a good reason.

When I visited a nearby observatory it was fun driving on the mountain and seeing the signs telling you to use engine braking on the way down and trying it for the first time.

?! - I'm clearly missing something because I'm failing to understand how people don't know about engine braking or have just tried it for the first time, and actually have a licence. It's approximately lesson number four in typical driving tuition.

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

#727

Post by DamnInteresting »

kube-system wrote: post #675
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.

Some vehicles repurpose shift paddles as a way to trigger regen braking. But they're pretty gimmicky and not really useful for driving. If you want to use regen in a vehicle that supports it, the brake pedal does that. And when regen is not enough, the hydraulic brakes are also used. But a "sometimes brake" pedal that only support regen sounds like a bad idea. Vehicle controls as essential as braking need to be consi…

I've been driving a Chevy Bolt for over 8 years now, and I regularly use the regen paddle. I drive in "L" mode, which engages partial regen when the accelerator is released. When I need more slowing, I pull the paddle, and that increases the aggressiveness of the regen. I only press the brake for quick stops, or to hold the car once it has stopped.

I also use the built in "hilltop reserve" feature, which limits charging to 90%. This ensures that there is always regen resistance, and therefore a consistent experience.

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

#728

Post by p_j_w »

1234letshaveatw wrote: post #556
p_j_w wrote: post #518

Earlier quoted context omitted.

> feel free to go live in a dense cell block and eat bug juice if that is what floats your boat. That this is considered a valid response to someone suggesting we need more mass transit is a sign that our discourse has fallen off a cliff. You can and should do better.

Why is it that these "do better" suggestions always feel like an attempt to shut discussion down. Being anti-car does not make you some moral authority

"You want everyone to live in a prison cell and eat nothing but bugs" is not discussion.

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

#729

Post by altairprime »

p_j_w wrote: post #529
altairprime wrote: post #351

Earlier quoted context omitted.

The difficult is not electricity prices; those can simply be tariff'd for overhead-slash-profit as all U.S. chargers do already. The difficulty is building out hundreds of chargers within a single city block's worth of the city's x,y grid. That level of power density is generally only seen in heavy industrial zones, and residential distribution grids can barely cope with air conditioners, much less with electric vehi…

> I think that China has a significant advantage versus the U.S. — they are primarily selling very small vehicles for intra-city use This does not match what I’ve seen in China at all. Nor does it match up with any data I’ve seen about the best selling cars in China. Do you have any data on this?

Nope, but I have a pile of napkins here covered in scribbles. Appreciate the correction.

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

#730

Post by ajross »

ARandumGuy wrote: post #618
numpad0 wrote: post #389

Earlier quoted context omitted.

It's just that Tesla didn't spend skill points on brake blending tech unlockable. Some people confuse it as being a piece of technology of its own. Every other EVs and HVs assign first half of brake pedal for regen and bottom half for mechanical brakes. Tesla uses bottom half of gas pedal for the same, which eliminates the need to accurately determine the appropriate pedal force that corresponds to intended braking f…

This is something that's always baffled me about Teslas. I have a Prius, and regenerative breaking being tied to the break pedal is easy and intuitive. It also means I can easily lift my foot of the gas pedal to coast. IDK it just seems like a much better design to have one "stop" pedal and one "go" pedal, vs one "stop" pedal and one "go/stop" pedal.

Counterargument is that it's even easier to have only one pedal you use to accelerate and decelerate. Having owned a Prius and a Y, the Tesla is actually smoother to control, by a very significant margin. It's actually a superior way to drive, though it is surprising the first time you see it.
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