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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

#621

Post by sofixa »

1234letshaveatw wrote: post #552
ceejayoz wrote: post #520

Earlier quoted context omitted.

It's hard to share a cell phone. If there are opportunities to make them more environmentally friendly (longevity, production processes, better batteries, etc.) we should absolutely try to do those things. EVs are better than ICE cars, but shared-use buses/trains/etc. are often even better. We can do more than one thing.

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 fundamentally wrong to gatekeep all of society behind a fundamentally inefficient manner of transport (individual cars). It's wrong socially (no social mobility), it's wrong ecologically (cars are still the most polluting way of transportation, even EVs), it's wrong economically (very inefficient), it's wrong from the amount of people dying from cars, it's wrong on every possible measurable metric.

So, alternatives should be present, so that those that wish to do so, or for whom it's better/faster/more efficient/can't use anything else because of mobility issues/can't afford anything else, they can take them. Bike lanes, trains, buses, whatever, doesn't matter.

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

#622

Post by ARandumGuy »

ajross wrote: post #525
tbrownaw wrote: post #136

Earlier quoted context omitted.

> 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…

I won't speak to your '22 Escape, but I've driven countless hybrids going back to a '04 Prius and none of them were brake-free in general use. EVs really are.

That's because the regenerative braking is applied on the brake pedal, not by lifting up the accelerator. My '14 Prius has a dashboard option to show how much of the regenerative breaking capacity is being used, and it's very easy to stay well below that limit by just gradually slowing down. The friction brakes are only really used when you suddenly stop, which is something you want to avoid anyway.

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

#623

Post by Sohcahtoa82 »

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

Either you're lying about your driving habits, or there's something wrong with your car.

I've got a Model 3 Performance which came with the Michelin Pilot Sport 4 tires which are only warrantied for 30,000 miles. I had them for 5 years and 35,000 miles and they STILL had plenty of tread left. I had to replace them anyways because I hit a nasty pothole that caused the tread to separate.

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

#624

Post by NewJazz »

slt2021 wrote: post #593
NewJazz wrote: post #578

Earlier quoted context omitted.

That doesn't answer my question even a little bit.

From the physics perspective, where does kinetic energy go in E=1/2mv^2 ? Up to 60% goes back to battery, part goes to air resistance and rolling tire resistance (can be ignored for our case as its the same regardless of regen setting), the rest goes to friction of tire/road due to slowing down tire speed

Your claim was that most of the tire wear for cars was due to deceleration. Acceleration could be to blame too. I asked for a source for your claim, not math equations.

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

#625

Post by Sohcahtoa82 »

taeric wrote: post #594
RegnisGnaw wrote: post #554

Earlier quoted context omitted.

The post is talking about most people drive with BEV , which is one pedal driving. My Tesla does one pedal driving my default. China has banned "one pedal driving" as a default.

I took it to be people that are far more aggressive with the gas pedal than they really need to be. That is, it was more the heavy foot than it was letting off to brake. Regardless, your point stands. People that have gotten used to not directly using brakes to indicate you are slowing down is a dangerous thing with how reliant we are on the standard indications that you are slowing. All the more so if you need to ra…

> People that have gotten used to not directly using brakes to indicate you are slowing down is a dangerous thing with how reliant we are on the standard indications that you are slowing.

Most, if not all, EVs will light up the brake lights when you're slowing via regen braking as long as the deceleration rate is above a certain threshold. I know my Tesla does.

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

#626

Post by bethekidyouwant »

Zambyte wrote: post #569
jjayj wrote: post #33

Earlier quoted context omitted.

I would love to have gone electric (bought a car in September) but I rent and don't have any way to charge at my residence. How do we solve the renters-that-cant-charge-their-cars problem?

> How do we solve the renters-that-cant-charge-their-cars problem? By solving the renters-think-they-need-to-own-a-car problem.

We don’t have a housing problem. We have a people think they need a room with a window problem.

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

#627

Post by klaff »

taeric wrote: post #542
theshrike79 wrote: post #397

Earlier quoted context omitted.

This is the thing with good hybrids. The "gas pedal" becomes a "I want to go faster/slower" pedal, its position has zero impact on the RPM. As an anecdote: A security company I know only buys Toyota Hybrids for their guards just because of that. They have a habit of driving cars like they stole them and normal ICE cars break down from that kind of abuse. Hybrids won't let you abuse them, they pick the RPM and you dea…

This is less a hybrid thing and more a new transmission thing. It, of course, isn't free. The efficiency of a CVT is a good 10-20 percent lower than previous transmissions. That said, currently, the win from keeping the engine at either the max power or the max efficiency speed is substantial. There are some really good videos out there going over how newer CVTs work. Looks like some people are working on ones that a…

I have a Subaru (ten years old w/ >200k miles on it's chain-type CVT), and I thought the justification for it was that it was more efficient than previous systems.

From a mechanical engineering standpoint, the Subaru CVT uses a fairly conventional lock-up torque converter at the input, but that gets locked as you pass something like 15-20 mph (once the lowest gear ratio is satisfactory w/o the torque converter function) and beyond that all shifting of the CVT is done w/ the torque converter locked. In addition, the clamping force of the sheaves is adjusted per the torque load of the transmission to minimize the frictional losses.

Anyway I'm curious about data comparing efficiency of conventional and CVT automatics.

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

#628

Post by bethekidyouwant »

esperent wrote: post #373
nottorp wrote: post #313

Earlier quoted context omitted.

Yes, especially on the 6th floor :)

Well, that's an apartment. We're talking about house owners.

So not the city. Can’t wait till we ban ice vehicles from the suburbs.

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

#629

Post by [deleted] »

ZeroGravitas wrote: post #425
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...

Yes, but only to some degree. Quote from the actual report: > As the level of electrification of a vehicle rises, the dependence on regenerative braking also increases, thus lowering PM emissions from brake wear. Based on recent evidence [30], regenerative braking can reduce, in the worst- case scenario (i.e. highest usage of mechanical brakes or equivalently lowest usage of regenerative braking), brake wear emission…

[deleted]

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

#630

Post by dunham »

whycome wrote: post #588
janosch_123 wrote: post #540

For DIY EV conversions (I built some cars) you usually hook up the "regenerate braking" to the brakelight switch. So as soon as you tap the brake pedal just a little, you start regenerating and see the amps flow back into the battery (I have a little display on my dashboard). Only when you press the pedal further, do you start engaging the friction brakes. I have no statistics on brake pad differences because we didn…

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.

I did this with manual, and my EV does this with a single pedal control. Letting off of the pedal will engage regenerative breaking to the extent that you let off the pedal, it does not engage the brakes. I find that in a lot of city driving I don't need the brakes, but they do work fine when I need them. I really like this functionality. The car can also creep along at 1-2 Mph when necessary - so I don't need brakes to deal with slow traffic. (With a manual, first gear would sometimes suffice for this.)

So the premise in the title of the article does not surprise me, but I thought that the primary pollution complaint about electric vehicles was tire pollution and not brake dust.

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