Dust from car brakes more harmful than exhaust, study finds • Hacker News Board

Re: Dust from car brakes more harmful than exhaust, study finds

#171

Post by dv_dt » Sat, Feb 15, 2025, 6:37 PM UTC

blackeyeblitzar wrote: post #111

orev wrote: post #88

The Yale article and the paper both highlight the fact that EVs use regenerative braking and produce less dust. I was worried that this was a rehash of the astroturf campaign from a few years ago focusing on EV weight and how that was so bad for the environment because of tire and road wear. Unfortunately you need to read through the whole thing (instead of the headline and a few paragraphs) to see that information.

Has someone actually measured that tradeoff (weight versus regenerative braking) to determine where it is an even tradeoff? And surely regenerative braking has its own shedding of particles from all the moving parts.

Owning a hybrid with regenerative braking vs a non-hybrid of the same class of vehicle, there is a noticeable reduction in brake wear and replacement with regenerative braking.

Re: Dust from car brakes more harmful than exhaust, study finds

#172

Post by Schiendelman » Sat, Feb 15, 2025, 6:37 PM UTC

snozolli wrote: post #159

blackeyeblitzar wrote: post #111

Earlier quoted context omitted.

Has someone actually measured that tradeoff (weight versus regenerative braking) to determine where it is an even tradeoff? And surely regenerative braking has its own shedding of particles from all the moving parts.

surely regenerative braking has its own shedding of particles from all the moving parts. It adds tire wear, but no more than traditional friction braking. I can't see how there would be any measurable wear from any other moving parts, since it's just using a magnetic field for resistance. There are moving parts that touch, but modern, sealed bearings last a ridiculously long time.

Regenerative braking has much less tire wear than traditional braking because it's done much more slowly and smoothly.

Also, none of these discussions use up-to-date information on EV tires. Consumers aren't willing to replace their tires much more often for an EV except at the high end of the market, tire manufacturers are already making tires last much longer for EV purposes. New designs are already shedding less dust per unit mass of the vehicle than they were a few years ago.

Plus, some manufacturers are now working to reduce the toxicity of their formulas. This will eliminate the issues a lot more.

Re: Dust from car brakes more harmful than exhaust, study finds

#173

Post by masklinn » Sat, Feb 15, 2025, 6:39 PM UTC

thatcat wrote: post #11

dweekly wrote: post #4

I wonder if this will spur mandatory regenerative braking in all cars, eventually, as a means of reducing pollutants?

You can gear down in a manual transmission ICE to achieve similar reduction effects, but I doubt they will bring back manuals.

That is significantly more involved (and for most people less comfortable) than regen braking, which just... happens. Many (most?) EVs will also do blended braking when using the braking pedal, so even when you brake "manually" you're still not using physical brakes unless you really step on it.

Re: Dust from car brakes more harmful than exhaust, study finds

#174

Post by Schiendelman » Sat, Feb 15, 2025, 6:39 PM UTC

actionfromafar wrote: post #165

ComputerGuru wrote: post #87

Earlier quoted context omitted.

Every study I've seen concurs that EVs chew through tires faster than their equivalent ICE vehicle, and generate more tire particulate matter accordingly. The reasons (torque and weight) are unambiguously greater in an equivalent EV vs ICE. EVs do generate lower brake particulate matter, by virtue of not using them as much (otherwise they'd also be prone to generating more in a (faulty) per-engagement direct comparis…

Studies are always good, but it almost trivially follows that the tread loss must go somewhere.

EV specific tires have basically eliminated the difference in tread loss already. And because there's public pressure on this, the toxicity of the materials and tires is decreasing rapidly.

Every study I've seen from people pushing on this uses very old information about tires, proving there's a problem really requires updated work taking these things into consideration.

Re: Dust from car brakes more harmful than exhaust, study finds

#175

Post by Schiendelman » Sat, Feb 15, 2025, 6:40 PM UTC

uxp100 wrote: post #168

prododev wrote: post #54

Earlier quoted context omitted.

Can you share them? Because physics says that damage to roads scales quadratically with weight. Not sure why tires would not experience a similar increase. At the very least, these tires are subject to higher forces due to the heavier weights of EVs. Intuitively, consistently applying higher friction forces to an object would cause higher wear.

The weights aren’t really that much higher than ICE cars, but I don’t think anyone who has owned an EV would say they don’t go through tires faster. They do. How much due to weight, how much due to better acceleration, I don’t know, but they definitely are harder on tires.

Three or four years ago, yes. Newer EV specific tires don't seem to be wearing faster.

Re: Dust from car brakes more harmful than exhaust, study finds

#176

Post by AnthonyMouse » Sat, Feb 15, 2025, 6:40 PM UTC

dijit wrote: post #158

AnthonyMouse wrote: post #149

Earlier quoted context omitted.

That hasn't shown up in the fatality statistics for motorcycles. Sometimes more dangerous is just more dangerous.

I’d appreciate it if there was an attempt to actually engage here, this is hardly the gotcha you might think. Most fatalities of motorcycles are due to collisions with cars, not other bikes nor pedestrians. Diligence won’t save you if a driver unexpectedly swerves into you. Undoubtedly there are stupid people and people who are more likely to take more risks will be more likely to engage in motorcycle riding; creatin…

> Diligence won’t save you if a driver unexpectedly swerves into you.

That's the point. Diligence won't save you but crumple zones might have.

It's also not obvious that most collisions being with cars isn't just because most other vehicles are cars. If two motorcycles collide with each other at high speed, the damage they do to each other isn't your problem, it's the resulting loss of control and the damage to your body when you impact the pavement.

> Letting cars drive on pavements isn’t permitted for the same reason e-bikes shouldn’t be in traffic (or on the pavement).

But then you're stuck between three bad options: You have separate roads specifically for e-bikes (implausible), you put high speed e-bikes in pedestrian zones, or you limit the top speed of e-bikes to something safe for pedestrians and then people go back to buying cars because e-bikes are too slow.

Re: Dust from car brakes more harmful than exhaust, study finds

#177

Post by throwaway_5633 » Sat, Feb 15, 2025, 6:41 PM UTC

blackeyeblitzar wrote: post #111

orev wrote: post #88

The Yale article and the paper both highlight the fact that EVs use regenerative braking and produce less dust. I was worried that this was a rehash of the astroturf campaign from a few years ago focusing on EV weight and how that was so bad for the environment because of tire and road wear. Unfortunately you need to read through the whole thing (instead of the headline and a few paragraphs) to see that information.

Has someone actually measured that tradeoff (weight versus regenerative braking) to determine where it is an even tradeoff? And surely regenerative braking has its own shedding of particles from all the moving parts.

I heard from someone working at a big car producer that they force EV’s to use the mechanical brakes every now and then because if not, they rust away.

Re: Dust from car brakes more harmful than exhaust, study finds

#178

Post by robin_reala » Sat, Feb 15, 2025, 6:41 PM UTC

Fronzie wrote: post #170

blackeyeblitzar wrote: post #111

Earlier quoted context omitted.

Has someone actually measured that tradeoff (weight versus regenerative braking) to determine where it is an even tradeoff? And surely regenerative braking has its own shedding of particles from all the moving parts.

There are EV's which have drum-brakes. That's only possible because the regenerative braking takes most of the load. Also, there are stories of brake-discs rusting out on EV's. Both point to less (friction)-brake use on an EV compared to an ICE.

Yeah, my VE id.3 has drums on the back and disks on the front. Apparently the brake pads are effectively life-of-the-vehicle items under normal driving conditions.

Re: Dust from car brakes more harmful than exhaust, study finds

#179

Post by tim333 » Sat, Feb 15, 2025, 6:42 PM UTC

AnthonyMouse wrote: post #110

ndsipa_pomu wrote: post #60

Earlier quoted context omitted.

Also in the UK and I certainly subscribe to r/fuckcars as I'm a keen cyclist and never got around to learning to drive. I find it annoying that media outlets (BBC - I'm looking mainly at you!) will refer to EVs as being car-shaped and then, as you said, demonise e-bikes by lumping them in with the illegal e-motorbikes (see the recent Panorama program for a clear case of not making clear the distinction between e-moto…

> However, if we get as many people to use e-bikes or e-scooters, then the size and weight issues pretty much disappear. I still don't understand how they expect to solve the occupant safety issue though. Cars travel at high speeds but have crumple zones and airbags. E-bikes travel at the same speeds but if you crash, you die. And 2-wheeled vehicles are easier to crash. The fatality rate for motorcycles is astonishin…

The safety is a function of the speed you are going. Legal ebikes in the UK are limited to 15mph which is normally survivable unlike say a 125cc scooter doing 60mph.

I've got an ebike in central london and find it quite practical on the whole. For local journeys <2miles it's faster than anything else and you can go down mostly traffic restricted roads. For intercity you can put the bike on a train. Rain is a bit of a pain.

Re: Dust from car brakes more harmful than exhaust, study finds

#180

Post by talldatethrow » Sat, Feb 15, 2025, 6:42 PM UTC

blackeyeblitzar wrote: post #111

orev wrote: post #88

The Yale article and the paper both highlight the fact that EVs use regenerative braking and produce less dust. I was worried that this was a rehash of the astroturf campaign from a few years ago focusing on EV weight and how that was so bad for the environment because of tire and road wear. Unfortunately you need to read through the whole thing (instead of the headline and a few paragraphs) to see that information.

Has someone actually measured that tradeoff (weight versus regenerative braking) to determine where it is an even tradeoff? And surely regenerative braking has its own shedding of particles from all the moving parts.

My Chevy volt has 199k miles and it's original brake pads and rotors are definitely almost new looking, but I'd say to be conservative they are 60%.

My cheap Chinese Walmart tires have lasted me 50k miles and are due to be replaced soon, but I spend zero attention to driving smoothly or in an eco mindset.