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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

#301

Post by NoPicklez »

lm28469 wrote: post #255
NoPicklez wrote: post #198

The credibility and purpose of the article was shot down when they said the problem would be getting WORSE with EV's. Firstly, the problem becomes less of an issue with EV's and they shared no evidence to support that moving to EV's would increase non-exhaust based pollution. Lastly, there have been plenty of studies over the last two decades which show charged particles from car brakes.

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

You cannot infer that just because a car is ~50% heavier that it means it spews out more brake particles. EV's use regenerative braking similar to that of engine braking in your car and this accounts for limited use of the brake pads in comparison to combustion engines.

Those numbers you present are a little inflated when it comes to like for like currently. Furthermore, there are combustion engine vehicles which are far far heavier than EV 4wd's.

Acceleration is not performed under braking either so I don't see your latest point.

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

#302

Post by blagie »

scottyah wrote: post #300
blagie wrote: post #285

Earlier quoted context omitted.

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%.

Isn't the point to have a positive pressure system, so unfiltered air doesn't come in?

A hospital has many rooms, hallways, etc. Which is under positive pressure?

If you have two patients, they should both be isolated from each other. Which one gets the higher pressure, and which the lower?

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

#303

Post by fy20 »

beezle wrote: post #169
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.

Inspection station in my state made comment to me that EVs are failing inspection for rusted brake components because of their heavy use of regen. Add to cost of ownership.

I own a 2010 Prius and I've had to replace the brake pads more often than a regular car because of this, around every two years or 20k miles. I've had to replace the brake rotors twice over 80k miles, as the pads rusted and then wore it down unevenly.

Below 5mph the brakes are used, but it doesn't seem to be enough. Compared to my ICE car they always look a lot worse, and after parked for a day when it's damp have surface rust.

As another comment says, it seems like a software change could fix it by using the physical brakes more. I believe the issue is they get wet, and then don't get hot enough to dry out before parking.

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

#304

Post by AnthonyMouse »

k8sToGo wrote: post #247
AnthonyMouse wrote: post #231

Earlier quoted context omitted.

There is a decent sized gap between 0 acceleration and 0 regen equal to the amount of energy required for the vehicle to maintain speed against rolling resistance and air resistance. Anywhere inside that gap, you're not using regenerative braking at all, you're just decelerating from not supplying enough power to maintain speed.

That is not the type of cruising this is referring to. It is the wrong name, to be fair. It really is just letting the car roll.

"Just letting the car roll" results in deceleration, but at a rate chosen by physics rather than you. If deceleration is not what you want, you have to continuously apply power. If it is what you want, it's still almost never going to be at the rate you want, so you still either have to apply some power or apply some braking. In the former case, you're pressing down on the pedal enough that no regenerative braking is happening. In the latter case, regenerative braking is obviously more efficient than friction braking, because the latter has 100% losses to heat.

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

#305

Post by [deleted] »

blagie wrote: post #302
scottyah wrote: post #300

Earlier quoted context omitted.

Isn't the point to have a positive pressure system, so unfiltered air doesn't come in?

A hospital has many rooms, hallways, etc. Which is under positive pressure? If you have two patients, they should both be isolated from each other. Which one gets the higher pressure, and which the lower?

[deleted]

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

#306

Post by lm28469 »

NoPicklez wrote: post #301
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...

You cannot infer that just because a car is ~50% heavier that it means it spews out more brake particles. EV's use regenerative braking similar to that of engine braking in your car and this accounts for limited use of the brake pads in comparison to combustion engines. Those numbers you present are a little inflated when it comes to like for like currently. Furthermore, there are combustion engine vehicles which are…

And ICE use engine braking, I can drive with almost no use of the brakes, is it how most people drive? Certainly not. Most teslas I see use the gas and brake pedal as on/off switches.

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

#307

Post by ipqk »

pornel wrote: post #183
ipqk wrote: post #166

Earlier quoted context omitted.

And EVs make some problems worse, such as tire dust because they're heavier than an equivalent ICE car.

It's a shame this is used as an excuse to keep the heavy ICE SUVs and trucks. There are many EVs lighter than an average pickup truck. If people really cared about this, they'd demand train-based public transport instead (no tires! fully electric! self-driving too!), or at very least limits on car weight regardless of the engine.

Why do you think that was an excuse for ICE vehicles? That’s your own biases showing. I’m anti-car in general, and very pro public transit.

EVs aren’t going to be the savior of climate change. They do some things better than ICE cars, but do some things worse. Denying those worse things is just putting your fingers in your ears.

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

#308

Post by ipqk »

Retric wrote: post #179
yaomtc wrote: post #172

Earlier quoted context omitted.

They said tire dust, though, and I don't see an "edited" note there

Said breaks when I replied, though the article is talking about breaks so it’s an easy slip up.

Sorry, I meant tires, but momentarily mixed it up with brakes.

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

#309

Post by Retric »

ipqk wrote: post #308
Retric wrote: post #179

Earlier quoted context omitted.

Said breaks when I replied, though the article is talking about breaks so it’s an easy slip up.

Sorry, I meant tires, but momentarily mixed it up with brakes.

Thanks, it's fine.

I thought the post had changed, but I wasn't 100%

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

#310

Post by NoPicklez »

lm28469 wrote: post #306
NoPicklez wrote: post #301

Earlier quoted context omitted.

You cannot infer that just because a car is ~50% heavier that it means it spews out more brake particles. EV's use regenerative braking similar to that of engine braking in your car and this accounts for limited use of the brake pads in comparison to combustion engines. Those numbers you present are a little inflated when it comes to like for like currently. Furthermore, there are combustion engine vehicles which are…

And ICE use engine braking, I can drive with almost no use of the brakes, is it how most people drive? Certainly not. Most teslas I see use the gas and brake pedal as on/off switches.

ICE engine braking in a normal car requires the driver to engage lower gears to slow down. EV's do this automatically, which is why you get regenerative braking in that regard. It's quite different.

Many EV's whilst engine braking is applied, also apply the brake lights.

Quote from Tesla's website for Low and Standard regenerative braking "Standard: Provides the maximum amount of regenerative braking. When you release the accelerator, Model Y slows down, reducing the need to use the brakes."

The effect of regenerative braking in an EV is much greater than that of an ICE under engine braking.

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