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Dust from car brakes more harmful than exhaust, study finds

e360.yale.edu

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

#211

Post by tim333 »

ndsipa_pomu wrote: post #198
tim333 wrote: post #179

Earlier quoted context omitted.

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…

They can provide assist up to 15.5 mph IIRC, but aren't limited to a top speed apart from your legs and/or finding a big hill.

Yeah. It's quite interesting watching it develop in London. Basically all the Deliveroo guys use ebikes, often converted mountain bikes. A fair number of commuters use the Lime bikes, though far less than who use the tube. We are also starting to see some ebike delievery van hybrids like the DPD ones here https://ebiketips.road.cc/content/advice/features/alternativ...

that could be a win for the environment and I guess they replace normal vans. And I just saw a two seater ebike taxi with a roof.

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

#212

Post by caycep »

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.

Granted, I would still rather them designed for lighter weight. But that’s a separate issue w suv culture which is bad for society and environment in general. Totally would buy a 3000 pound EV around the size of a euro hatch.

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

#213

Post by caycep »

bobsmooth wrote: post #199
iterateoften wrote: post #12

Having lived next to a semi-main street through a smallish California coastal city without much rain it is pretty eye opening how much black dirt and junk just coat everything next to the road. Walk down the street and touch a bush or any plant leaf and get a nice black hand in the process. The plants are covered, parked cars get covered and the inside of my apartment was covered. It wasn’t until I moved out that I s…

I live on the second floor near a road and my balcony furniture is always covered in black gunk.

There was that whole study with some additive in tire compounds, killing whole rivers of salmon until they figured out what it was

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

#214

Post by AnthonyMouse »

hansvm wrote: post #188
AnthonyMouse wrote: post #162

Earlier quoted context omitted.

The weight difference between a Model 3 and the average new car sold in the US is a negative number. The Model 3 is slightly lighter than the average new car. So the difference comes entirely from torque. But you could just... not have such a heavy foot.

The difference also comes from the grippier tires on the Model 3, the total tread volume on those tires compared to a smaller car, and that the Model 3 compared to the average car isn't apples to apples if you're looking at tire wear for ICE vs EV (to be fair, my car's too light to be apples to apples either, but if you look at comparably sized cars the Model 3 is heavier).

Electric cars don't have electric car-specific tires.

If you look at comparably sized cars the Model 3 is about the same. It's roughly the same size and weight as a BMW 3 series. And they're both around the size and weight of the average new car.

It's small electric cars that typically weigh more, because making the car smaller isn't the main way to make the battery smaller; reducing the range is. So then nobody really makes a small full electric car with a short range, because that market is served by plug-in hybrids that solve the range problem with a gas engine while still allowing you to do a few dozen miles a day as an electric car.

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

#215

Post by lukevp »

kstrauser wrote: post #207
m463 wrote: post #181

Earlier quoted context omitted.

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 ga…

Are you familiar with how disk brakes on a car operate? They’re essentially a hydraulic piston clamping the brake pads against the rotor. When you let off the brake pedal, the pressure is removed, but there’s not a “retraction” of any kind. So there’s no pressure but nothing is actually making that gap. That article was articulating basically that the piston, when not compressing the brake pads, should not be too far out, because that’s just unnecessary travel of the pedal, but it does not mean that the brake pads are somehow gapped away from the rotors.

Drum brakes by contrast have springs that retract the pads from the braking surface, so the OP has a very valid point.

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

#217

Post by melling »

hypercube33 wrote: post #206
eagerpace wrote: post #157

Earlier quoted context omitted.

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

Worried about heavy vehicles? The best selling vehicle is the Ford F-series.

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

#218

Post by redeux »

caycep wrote: post #212
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.

Granted, I would still rather them designed for lighter weight. But that’s a separate issue w suv culture which is bad for society and environment in general. Totally would buy a 3000 pound EV around the size of a euro hatch.

The Nissan Leaf is in the 3000 lbs range and a fairly small hatchback.

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

#219

Post by bovermyer »

I wonder about the larger context here, though. No matter what academic studies discover or examine, the rise of anti-intellectual culture suggests that we as a species are going to need to pivot to documentary efforts, in a hope that what we learn in isolation now survives to be acted on in a future, more exploratory, generation.

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

#220

Post by plasticchris »

robin_reala wrote: post #178
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.

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.

I’ve only had to change them one time on any car newer than 1990, after ~200k miles/10 years of use. For most people that qualifies as life of the vehicle, but there was plenty of life left.
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