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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

#131

Post by AtlasBarfed »

Reason077 wrote: post #118
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.

Not only does regenerative braking itself reduce PM emissions, the reduced demand on friction brakes is enabling some EVs, such as the Volkswagen ID3 and ID4, to switch to drum brakes. Due to their enclosed nature, drum brakes greatly reduce PM emissions compared to disc brakes.

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.

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

#132

Post by simne »

EForEndeavour wrote: post #37
jordanbeiber wrote: post #22

Earlier quoted context omitted.

But you rarely have to brake an EV though. I’ve had two EV’s over the last 6 years, and I have to remember to occasionally hit the brakes to keep them from rusting. One pedal driving is just money - saves power and is just much smoother over all than old school breaking. IMO.

I've never driven an EV. How do you approach stop signs and red lights other than braking? Is "engine braking" (regenerative braking?) strong enough to handle that big a fraction of slowing down in city traffic?

It depends. On new EVs (which formally designed as EV from scratch), motors and charger are usually powerful enough to exceed brakes.

On conversed, usual practice to limit torque of motor to be less than on ICE original, because of regulations (which exactly state, electric motor should not exceed ICE torque), and this mean, they are just not powerful enough for 100% regenerative braking.

From technical view, modern electric engine could easy exceed brakes.

I'm member of Ukrainian EV activists group, and we there mostly talk about conversions. Unfortunately, conversions are not so cool as new EVs, but to be honest I don't know details of other countries regulations, they could be less restrictive.

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

#133

Post by Karellen »

xdavidliu wrote: post #129
imbusy111 wrote: post #95

Earlier quoted context omitted.

The article has weird reasoning. If we remove tailpipe emissions, which are by far the largest, then brake/tire wear emissions become visible and are next in the list to deal with. But we won't deal with the latter before the former is dealt with.

> If we remove tailpipe emissions, which are by far the largest im gonna need a source on your claim. heres a source that claims the opposite https://www.washingtonpost.com/climate-environment/2023/07/0... > our brakes and tires isn’t benign, either. Tests by Emissions Analytics, an engineering consulting company based in England, found tires produce about 2,000 times more particle pollution by mass than tailpipes.

> tires produce about 2,000 times more particle pollution by mass than tailpipes.

(emphasis mine)

The fact that the majority of tailpipe pollution is not particulate means that tailpipe pollution can be the biggest problem we need to fix, even if it isn't the biggest particle pollution problem.

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

#134

Post by jasonfarnon »

autoexec wrote: post #124

The problem of "brake dust" on human health and air quality has been known for a long time ( https://phys.org/news/2020-01-air-pollution-effects-immune-c... ) before that there were also issues with asbestos in brakes, but thankfully those haven't been used since the 90s as far as I know. This is the first I'm hearing about electrically charged particles though. The bottom line is that proximity to traffic is horribl…

If you looked nationally at wealth vs proximity to traffic, I would wager the "people with the least amount of money" are not the closest to traffic; are you suggesting otherwise? If only because of all the wealth that has come to cities in the last 20-25 yrs. Within that already wealthy urban demo I would agree, yes, the poorer wealthy are nearer to urban highways and thoroughfare than the wealthier wealthy.

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

#135

Post by actinium226 »

thejazzman wrote: post #79
techdmn wrote: post #64

Earlier quoted context omitted.

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…

It DOES bring them to a stop in newer models. Not sure which year it started but it's been at least 2 But I know what you mean from my older models

Are you talking about the hold mode they introduced a couple years back? It will bring the car to a stop but (as compared to the previous mode where you had to press the break yourself below ~4-5 mph), but I'll be good money it's using the brakes to do so. Particularly when it's activated on an incline.

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

#136

Post by CharlesW »

jasonfarnon wrote: post #134
autoexec wrote: post #124

The problem of "brake dust" on human health and air quality has been known for a long time ( https://phys.org/news/2020-01-air-pollution-effects-immune-c... ) before that there were also issues with asbestos in brakes, but thankfully those haven't been used since the 90s as far as I know. This is the first I'm hearing about electrically charged particles though. The bottom line is that proximity to traffic is horribl…

If you looked nationally at wealth vs proximity to traffic, I would wager the "people with the least amount of money" are not the closest to traffic; are you suggesting otherwise? If only because of all the wealth that has come to cities in the last 20-25 yrs. Within that already wealthy urban demo I would agree, yes, the poorer wealthy are nearer to urban highways and thoroughfare than the wealthier wealthy.

https://www.cdc.gov/mmwr/preview/mmwrhtml/su6203a8.htm

"In the United States, it is widely accepted that economically disadvantaged and minority populations share a disproportionate burden of air pollution exposure and risk (26,27). A growing body of evidence demonstrates that minority populations and persons of lower socioeconomic status experience higher residential exposure to traffic and traffic-related air pollution than nonminorities and persons of higher socioeconomic status (5,28–31). Two recent studies have confirmed that these racial/ethnic and socioeconomic disparities also exist on a national scale (32,33)."

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

#137

Post by simne »

It is known problem. May be most researched is "brake dust" in tube, where it is literally seen with naked eye. Other place where "brake dust" seen but nobody care, in airplanes, may be because airplane brakes are not just emit dust, but literally smoke :)

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

#138

Post by jasonfarnon »

CharlesW wrote: post #136
jasonfarnon wrote: post #134

Earlier quoted context omitted.

If you looked nationally at wealth vs proximity to traffic, I would wager the "people with the least amount of money" are not the closest to traffic; are you suggesting otherwise? If only because of all the wealth that has come to cities in the last 20-25 yrs. Within that already wealthy urban demo I would agree, yes, the poorer wealthy are nearer to urban highways and thoroughfare than the wealthier wealthy.

https://www.cdc.gov/mmwr/preview/mmwrhtml/su6203a8.htm "In the United States, it is widely accepted that economically disadvantaged and minority populations share a disproportionate burden of air pollution exposure and risk (26,27). A growing body of evidence demonstrates that minority populations and persons of lower socioeconomic status experience higher residential exposure to traffic and traffic-related air pollu…

It's not surprising that minorities would be exposed to more traffic given the proportion that live in urban areas, but that doesn't rule out that the poorest in the country (minorities and whites) are not the most exposed. I guess my basic question is, are the poorest people still living in city centers? In my city the central, densest areas became some of the wealthiest, the quieter outlying areas the poorest.

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

#139

Post by Reason077 »

AtlasBarfed wrote: post #131
Reason077 wrote: post #118

Earlier quoted context omitted.

Not only does regenerative braking itself reduce PM emissions, the reduced demand on friction brakes is enabling some EVs, such as the Volkswagen ID3 and ID4, to switch to drum brakes. Due to their enclosed nature, drum brakes greatly reduce PM emissions compared to disc brakes.

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.

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

#140

Post by zamfi »

thejazzman wrote: post #79
techdmn wrote: post #64

Earlier quoted context omitted.

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…

It DOES bring them to a stop in newer models. Not sure which year it started but it's been at least 2 But I know what you mean from my older models

To be clear this is a software setting now, on all (I think?) Teslas.
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