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Vehicle brakes produce charged particles that may harm public health: study

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Re: Vehicle brakes produce charged particles that may harm public health: study

#281

Post by kjkjadksj »

Tade0 wrote: post #259
jasonwatkinspdx wrote: post #206

A startup I worked for years ago initially had a temporary office in a coworking space that catered to artists and craftspeople, in a renovated warehouse near the freeway loop downtown. They didn't have air conditioning, which isn't particularly strange in the PNW, but we did learn opening the windows for breeze was a very bad idea. The amount of tire and brake dust/soot that would pile up in a single afternoon was d…

I went to Switzerland once and as I walking over a bridge stretching above a highway, I noticed the smell of hydrocarbons and machinery in general. It takes Alpine air as a point of reference to feel it, which says a lot about the ambient level of pollution in cities.

In Wilmington, CA, the pollution from refineries and the port of LA is often so intense that you can smell it within your car as well as see the brown tinge that hangs thick and low in the air driving southbound into the area. Its amazing that people still have to live under that today in this state of supposed environmental leaders both public and private. I guess the port makes too much money for the economy for anyone to care about the health outcomes of the people who are saddled with living near it.

Re: Vehicle brakes produce charged particles that may harm public health: study

#282

Post by Tagbert »

helsinkiandrew wrote: post #269
za3faran wrote: post #265

Earlier quoted context omitted.

EVs also tend to be heavier than their ICE counterparts.

> EVs also tend to be heavier than their ICE counterparts. As the parent comment said - but I was questioning about whether increased torque has an actual impact on tyre wear.

In my experience, someone who is new to EVs will tend to do a lot of short, fast accelerations to explore how the vehicle performance. That happens mostly in the early stages of using an EV and after a while they settle in to a more normal (ICEV similar) acceleration pattern.

Re: Vehicle brakes produce charged particles that may harm public health: study

#283

Post by Tagbert »

Reason077 wrote: post #139
AtlasBarfed wrote: post #131

Earlier quoted context omitted.

And the brakes are only employed if needed. So even if you had disc brakes and has a good Regen design, you'd only use them in aggressive /emergency situations. The other benefit of EVs is that the feedback on regeneration and efficiency tends to make you less aggressive and a better driver. Which also leads to less brake use.

Yes, although worth remembering that many EVs are rear-wheel drive only. An all-wheel drive or front-wheel drive EV can regen more effectively than one which can regen on the rear wheels only.

I understand the theory of that but wonder how much difference there actually is.

Re: Vehicle brakes produce charged particles that may harm public health: study

#284

Post by Tagbert »

hristov wrote: post #241
daft_pink wrote: post #87

Just want to point out that most electric and hybrid vehicles use regenerative braking most of the time and only use real brakes at very slow speeds or in emergencies. So it might be totally misleading to say that electric vehicles are the problem, when they are probably the solution.

Absolutely right. I had to change brake pads on my electric car at about 120 k miles. My previous gasoline cars usually had their brake pads last about the advertised 30K miles. Some people are complaining that the rear brake rotors of their teslas are rusting and looking bad. That is how little they are used. Furthermore, it is entirely possible and probably desirable that some electric cars actually remove the brak…

Regen has limitations in how quickly the power can be stored which limits the braking rate. Also, when the battery is fully charged there is no place to put the electricity which also limits regen braking.

Most EVs blend regen into the brakes so that when you press on the brake pedal it uses regen for normal braking down to about 10mph at which point the friction brakes take over. At low speeds regen is ineffective. That low speed use of friction brakes produces very little wear and very little particulate output.

Those EVs doing blending will also switch entirely to friction braking if you really stomp on the brake pedal in an emergency stop as you can stop more quickly than any regen system. In those cases the priority is stopping quickly regardless of energy efficiency or particulates.

I don’t see a likely hood that EVs will completely get rid of friction brakes using current/near term technology.

Re: Vehicle brakes produce charged particles that may harm public health: study

#285

Post by blagie »

zanfr wrote: post #272
blagie wrote: post #268

Earlier quoted context omitted.

Filtration is a very good idea. HEPA filtration for residential use is dumb. A HEPA filter must remove at least 99.97% of aerosols 0.3μm in diameter. A filter which removed 99% and blows air 1% faster will remove just as much, or one which removes 50% and blows air twice as fast. For recirculating air, all of those accomplish the same thing. Some of those have much higher noise, running costs, and general upkeep than…

would be about time we HEPA'd everything in health care

Why?

HEPA doesn't matter unless you have a sealed system. An open door or a cloth curtain means the 99.97% means nothing relative to 99%.

Re: Vehicle brakes produce charged particles that may harm public health: study

#286

Post by recursive »

recursive wrote: post #278
lm28469 wrote: post #255

Earlier quoted context omitted.

EVs are 50%-100% heavier and a lot of them accelerate faster than supercars from the 80s...

EVs tend to be heavier, but your numbers seem high. A Corolla sedan is +30% weight over a model 3. https://www.carsized.com/en/cars/compare/toyota-corolla-2018...

Edit: Meant to say a model 3 is heavier than the Corolla by 30%.

Re: Vehicle brakes produce charged particles that may harm public health: study

#287

Post by r00fus »

audunw wrote: post #266
yreg wrote: post #258

Earlier quoted context omitted.

I almost never use breaks. It is a game for me, so I'm conscious of any time I have to use them. On the other hand, EVs unfortunately pollute more with tire particles (thanks to both higher torque - especially from 0 - and higher average mass).

Do you have hard numbers on the tire particle claim? We have anecdotes of Tesla owners saying they go through tires more often. But I’ve also heard car fleet owners with both EVs and ICE saying they see no difference between them. So I’m inclined to think this is entirely dependent on the specific EV. You can get an EV without significantly more weight than an equivalent ICE, and you can drive them in ECO mode where…

I have a Ford Focus EV - still haven't replaced my brake pads - 7 years strong. Finally replaced my first set of tires last winter.

Re: Vehicle brakes produce charged particles that may harm public health: study

#288

Post by r00fus »

techdmn wrote: post #64
u320 wrote: post #3

Electric vehicles are heavier, which means they must spend more brake pads to stop. But they also use regenerative breaking, which reduces pad wear. So I'm not sure if they make it worse or not.

I drive a Tesla Model 3, a few thoughts: * I'm hard on brakes in general, but have over 70k miles on the original pads. Regen braking reduces brake use a LOT. * Regen does NOT bring the car to a complete stop, the brakes are blended in below something like 5 MPH. The rotors are not going to rust away, they see action every time you drive. (Some surface rust is fine and normal, EV or no.) * EVs can be heavier than ICE…

> * Regen does NOT bring the car to a complete stop, the brakes are blended in below something like 5 MPH. The rotors are not going to rust away, they see action every time you drive. (Some surface rust is fine and normal, EV or no.)

A Gen2 Leaf (2018+) with "e-Pedal" mode absolutely does stop the car fully with regen.

Re: Vehicle brakes produce charged particles that may harm public health: study

#289

Post by r00fus »

losvedir wrote: post #68
k8sToGo wrote: post #63

Earlier quoted context omitted.

Crusing is much more efficient than one pedal driving. So it does not save power at all.

Are there any cars that "cruise" (by which I assume you mean maintain velocity without applying a pedal)? Non-EVs mostly sort of do so, they still slow down gradually. I'd be interested in trying a car that cruises indefinitely. Sort of an automatic, always on cruise control.

Are you talking about basic cruise control that's been around since forever?

In the 90s I drove a Dodge Spirit from Florida to NY using cruise most of the way - the cruise adjustment was incredibly responsive.

Re: Vehicle brakes produce charged particles that may harm public health: study

#290

Post by Kodiack »

kjkjadksj wrote: post #279
davely wrote: post #228

Earlier quoted context omitted.

I don’t think this is a 1:1 comparison though. Electric cars can utilize regenerative braking, which can significantly slow them down before needing to use friction from brake pads in order to stop.

You can engine brake with a gas car if its manual transmission too

You can engine brake with a lot of automatic vehicles as well, since they’ll still have semi-automatic modes. I drive a car with a CVT and I’m able to “down-shift” for engine braking by using fake gears at specific ratios.
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