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Electric cars produce less brake dust pollution than combustion-engine cars

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Re: Electric cars produce less brake dust pollution than combustion-engine cars

#311

Post by dubbel »

mschild wrote: post #298
pkolaczk wrote: post #274

Earlier quoted context omitted.

I confirm and that’s an unpleasant surprise. Already had to replace the rear rotors and pads on my Highlander… because of rust. They should add some “brake cleaning” mode to temporarily disable regenerative braking.

> They should add some “brake cleaning” mode Also known as breaking. You could just do that once in a while.

If you don't break hard enough, it might still be the recuperation doing its work.

Car producers can and do resolve this, e.g. iirc Audis don't use recuperation for the first breaking of the day. That way you don't have to remember to use the no-recuperation/break cleaning mode or break unnecessarily hard every now and then.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#312

Post by MindSpunk »

agurk wrote: post #253
MindSpunk wrote: post #186

Earlier quoted context omitted.

It's not "nearly". It's exactly the same effect. Compression braking. Even if you're not on the throttle the engine is still rotating as it's connected to the wheels. If the engine is rotating it is compressing air. If it's compressing air but not igniting fuel (throttle closed) then it will suck energy out of the wheels to compress the air. You can do it in an automatic, you just have to force it to select a lower g…

If it takes energy to compress the air in the cylinder - doesn't it also release most of that energy when that compressed air is expanded on the subsequent stroke? If you release the compressed air without pushing the cylinder down you would lose that energy, but you would need a extra device to do so (by lifting a valve at the right time). This option does exist for large vehicles like trucks as a compression releas…

You're right. Petrol engines are air pumps so I should've realised the explanation wasn't correct.

Though the ECU would be doing the AFR management on modern EFI engines as the injectors aren't vacuum operated like Carburetors were. You should be able to cut fuel injection when coasting in a modern engine, can't run lean if there's no fuel at all. Not sure if carbs could do the same.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#313

Post by nottorp »

esperent wrote: post #260
nottorp wrote: post #238

Earlier quoted context omitted.

Why renters? I own but I still wouldn't have any place to charge if i owned an EV...

If you own a house, generally you can do things like install charging points (also backup batteries, solar panels, better insulation, all kinds of fun things) that renters can't. I'm sure there are some homeowners who can't - maybe listed buildings, or these weird HOA rules I hear about from Americans.

Yes, especially on the 6th floor :)

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#314

Post by rcMgD2BwE72F »

DataDaemon wrote: post #276

continuation of EV propaganda, which are much heavier cars.

Curb weight of a Tesla Model (Long Range) is only 9% over a comparable BMW 3 Series.

That's nothing compared to all the savings (tail pipes emissions, break dust, noise, ICE maintenance issues…). And we're just getting started with battery chemistries and renewables energy. This can only get better.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#315

Post by xnzakg »

pkolaczk wrote: post #274
fho wrote: post #184

Earlier quoted context omitted.

The rear brake rotors on my Yaris hybrid are basically always rusty because they get used so little. After some time you just know when to start braking so you only use regen instead of the brakes.

I confirm and that’s an unpleasant surprise. Already had to replace the rear rotors and pads on my Highlander… because of rust. They should add some “brake cleaning” mode to temporarily disable regenerative braking.

Many of the cars with regenerative braking already do apply the brakes once in a while to prevent them from rusting.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#316

Post by yakkers »

MindSpunk wrote: post #186
cloverich wrote: post #153

Earlier quoted context omitted.

Surprisingly you can get nearly same effect in automatics. I put around 60k miles on my first automatic (after120k+ on my first two cars, manual transmissions) and when i got my brakes checked at 63k they noted my brakes were still "brand new". I do gamify reading traffic to try and brake as little as possible (to help pass time etc), but was still surprised how far this takes you given i do plenty of stop and go tra…

It's not "nearly". It's exactly the same effect. Compression braking. Even if you're not on the throttle the engine is still rotating as it's connected to the wheels. If the engine is rotating it is compressing air. If it's compressing air but not igniting fuel (throttle closed) then it will suck energy out of the wheels to compress the air. You can do it in an automatic, you just have to force it to select a lower g…

An aside on your last point: In the D gear, a lot of auto transmissions will be set up to allow for the wheels to spin somewhat independently of the engine (in any gear) when you aren't accelerating, which accounts a lot for how well an automatic will coast when you release the throttle, even if you're not going fast enough for top gear (especially apparent with older four speed boxes).

Using the numbered gear options will enable clutches/bands that provide more engine braking.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#317

Post by sjducb »

jillesvangurp wrote: post #107
brtkwr wrote: post #4

An an EV owner, I can testify that the tyre wear more than makes up for the reduction in brake dust. I’ve had to change tyres every 10K miles.

Switch tire brand and type or get some advice. Whatever you are currently getting isn't the right tire for your car, obviously. You should be seeing much longer lives for your tires. Even with an EV. So, something is off. And tires of course aren't created equally. There are many different types of tires and they are optimized for different circumstances. If you mismatch your tires to e.g. weather conditions, you are…

Agreed parent needs to get advice from 2/3 different tyre shops. Changing tyres every 10k means something is wrong.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#318

Post by sjducb »

teleforce wrote: post #141
stephen_g wrote: post #5

Good to have more data points and evidence, but this seems extremely well established by now? Zero tailpipe emissions, drastically removed brake dust, slightly higher tire wear (due to weight), but much better overall than ICE.

>drastically removed brake dust It will be very interesting to see the data for the same car that has many powertrain versions for example the Lexus UX with the UX 200 (ICE), UX 300h (hybrid) and UX 300e (EV) to test which one the best and the worst in term of brake dust residue. My hypotheses is that for brake dust residue the best is hybrid, 2nd will be ICE and the 3rd will be EV. This is due to the fact that the E…

My EV doesn’t use the brakes in normal driving. It can pull ~ 0.3G of regen before the physical brakes engage.

It will regeneratively brake all the way to a stop.

The brake disks are there for emergencies and spirited driving.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#319

Post by whatevaa »

mschild wrote: post #298
pkolaczk wrote: post #274

Earlier quoted context omitted.

I confirm and that’s an unpleasant surprise. Already had to replace the rear rotors and pads on my Highlander… because of rust. They should add some “brake cleaning” mode to temporarily disable regenerative braking.

> They should add some “brake cleaning” mode Also known as breaking. You could just do that once in a while.

Sure, gonna slam on brakes while in front of you.

It's 2025 and hybrids have enough software to automate some non-hybrid braking action.

Re: Electric cars produce less brake dust pollution than combustion-engine cars

#320

Post by mattlondon »

jjayj wrote: post #33
rayiner wrote: post #16

We should obviously ban combustion engine cars, at least starting with cities. I can’t think of a single clearer win for air quality.

I would love to have gone electric (bought a car in September) but I rent and don't have any way to charge at my residence. How do we solve the renters-that-cant-charge-their-cars problem?

In the UK, in London at least, they're starting to put in more and more ~4-5KW chargers on the electric street lamps/lamp posts.

So far its like 1 or 2 a street (and not all streets either), but hopefully one day it will basically be all of them in every street so you don't need to worry.

So if you need to park overnight on the street anyway, park next to a lamp post that has the socket. Its "slow" charging at 4 to 5 KW, but if you're parked for 8-12 hours (while you are asleep), that is quite a considerable top-up in the 40-50KWh range.

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