Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Dust from car brakes more harmful than exhaust, study finds

e360.yale.edu

Post reply on HN
Print view View original

201–210 of 465 posts

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

#201

Post by ceejayoz »

rafaelmn wrote: post #190
Schiendelman wrote: post #172

Earlier quoted context omitted.

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 d…

Teslas eat tires for breakfast. Instant torque and high weight - any benefit you get from regen breaking is not scratching that.

This probably depends quite a bit on your acceleration/braking settings.

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

#202

Post by YZF »

rafaelmn wrote: post #190
Schiendelman wrote: post #172

Earlier quoted context omitted.

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 d…

Teslas eat tires for breakfast. Instant torque and high weight - any benefit you get from regen breaking is not scratching that.

My model 3 is 5 years old and I'm still on my original set of tires (though in recent years I do put on winter tires for a few months a year). I don't usually drive like crazy (and it's an SR+ which is the least powerful model).

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

#203

Post by silisili »

hristov wrote: post #196

This article is flat out wrong. The study they cite does not state the things the article says it states. And the study they cite certainly does not compare the harm from brakes to the harm from exhaust. The study simply says that brake dust can cause asthma and hay fever in children. There is no comparison made to the harm from exhaust. Exhaust is certainly more harmful than brakedust in the quantities one may encou…

Anecdote related to last paragraph...20 or so years ago I drove a then 20 year old truck some guy had cobbled together. It was a real hunk o junk, rusty, the speedometer didn't work, etc. But it did have a new engine and carb, but it had no cat. It had several exhaust leaks (judging by noise). I was lucky it even had mufflers.

Went through a taco bell drive thru one night that had a weird tunnel portion. It was a slow line, and even sitting in that tunnel a couple minutes, my friend and I got lightheaded and a bit teary eyed. It's scary we didn't even realize it til we got through the tunnel.

That was the moment for me of realizing how awful these things are for the environment. If we have to be enclosed with our own emissions it will literally kill us, but we just blow it away in the open air as 'not my problem anymore.'

I'm glad emissions are better now, and that electric has a viable path forward. Shame we weren't at this point a few decades ago.

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

#204

Post by montalbano »

ComputerGuru wrote: post #87
djaychela wrote: post #33

> with their increased weight and powerful torque, they produce a lot more tyre pollution than ICE vehicles. This has been shown not to be true in a number of studies.

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…

https://www.ch.cam.ac.uk/news/%E2%80%98illusion-truth%E2%80%...

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

#205

Post by AnthonyMouse »

dijit wrote: post #186
AnthonyMouse wrote: post #176

Earlier quoted context omitted.

> 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…

My point is cars don’t necessarily deserve the deference society affords them, they’re utility vehicles, needed by fewer people than we think (but still needed). The paths we reserve for car use should be diminished. If every person was driving an articulated truck then there would be more deaths, caused not just by collisions and poor driving but by emissions too. We’d need bigger roads too- its unnecessary for ever…

The general problem is that it's not that fewer people need them, it's that most people need them on fewer occasions, but they're not going to buy, register and insure separate vehicles for different uses. So they get one that does everything and use it for everything, and then they're driving an SUV even when they're traveling alone with no cargo.

To get away from this you'd have to completely redesign US cities to have people living in them instead of significant numbers commuting in from the suburbs. To begin with you'd need a massive amount of new higher density housing, the construction of which is currently inhibited by building codes where not outright prohibited by zoning. Trying to solve the rest of it before you do that is going to face massive opposition, because you'll be trying to make it harder to have a car to people who still can't realistically avoid having a car.

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

#206

Post by hypercube33 »

eagerpace wrote: post #157
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.

Regen braking uses magnets and takes place inside an encased and oil-cooled motor which should eliminate airborne debris.

Rubber still wears off tires though so that may be worse or not for heavier vehicles

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

#207

Post by kstrauser »

m463 wrote: post #181
Fronzie wrote: post #170

Earlier quoted context omitted.

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.

I suspect drum brakes were chosen by the electron pinching EV engineers. They're the only brakes that are friction-free when not applied. Disc brakes rub (and slow the car) even when not applied.

Not significantly. Otherwise they’d get hot and work less well. Pads ride very closely to the disc so that road stuff can’t get wedged between the surfaces, and so that you don’t waste break pedal travel just getting the pads close to the surface. Well adjusted drum brakes should be arranged almost exactly the same way.

From https://mechanicswizard.com/how-close-should-brake-pads-be-t...:

> Typically, the optimal gap between brake pads and rotors is between 0.5 and 1.5 mm (0.020 to 0.060 inches).

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

#208

Post by rafaelmn »

YZF wrote: post #202
rafaelmn wrote: post #190

Earlier quoted context omitted.

Teslas eat tires for breakfast. Instant torque and high weight - any benefit you get from regen breaking is not scratching that.

My model 3 is 5 years old and I'm still on my original set of tires (though in recent years I do put on winter tires for a few months a year). I don't usually drive like crazy (and it's an SR+ which is the least powerful model).

True, and you can do engine breaking and do milder acceleration curves in ICE car and that will significantly reduce the pad/tire wear. But if you drive like, I would speculate, most people do, Tesla will go through tires like a track car (half joking)

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

#209

Post by kstrauser »

snozolli wrote: post #183
Schiendelman wrote: post #172

Earlier quoted context omitted.

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 d…

Regenerative braking has much less tire wear than traditional braking because it's done much more slowly and smoothly. Absent any evidence, I don't believe that claim. Unless you're skidding, I don't see how braking slowly and smoothly over a longer period causes any less tire wear than braking more rapidly for a shorter time. Additionally, since this is intrinsically tied to EVs, they weigh more and thus increase ti…

That seems plausible to me. Tires are made from rubber. If friction forces exceed how strong the rubber particles stick to each other, they get pulled loose. And road surfaces aren’t perfectly smooth, so when you’re accelerating, some rubber particles will experience more force than others.

It seems believable that hard braking, even without leaving skid marks, could pull more rubber off a tire than gradual braking.

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

#210

Post by bluescrn »

light_hue_1 wrote: post #191
dijit wrote: post #106

Earlier quoted context omitted.

I find it hard to take the debate seriously because the default stance of everyone against electric 2-wheelers is not manual bikes, its cars. And, cars are multiple orders of magnitude more dangerous than anything on 2-wheels. I’m sure you’re right that theres room for improvement, but instead of building infrastructure (we literally shaped cities for cars after all)- we would rather ensure that cars are incumbent fo…

Are you replying to the right post? My default is my manual bike. No amount of infrastructure will make these electric motorcycles safe in bike lanes or pedestrian paths. They should be banned.

We don't ban cars or motorbikes because they're unsafe. We require a license and insurance then ban those who repeatedly break the rules of the road.

We need to find a sensible way to regulate these bikes, which may involve some sort of license, insurance, and mandatory helmets. But it needs to be less costly/more convenient than getting a petrol motorbike (or car) if we want people choosing the more eco-friendly option.

Cycling enthusiasts don't tend to consider those who are far less fit/healthy/young when they push the pure-human-powered option.

Post reply on HN