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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

#321

Post by robertlagrant »

scns wrote: post #304
usrusr wrote: post #285

Earlier quoted context omitted.

On paper, yes, but did that ever happen? Sorry for being sarcastic, but where I live the frugal hybrid is exceptionally rare and the "same big engine, but driving a much heavier car" hybrid is omnipresent. The kind of people who might buy the frugal one buy second or third hand while almost all buyers of factory new pick the "same big engine" option, and those are the ones who decide what's available on the second ha…

> did that ever happen? In 2010 with the Chevrolet Volt.

I think the question is "is that overall effect the reality, or do most people buy a very heavy hybrid?"

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

#322

Post by MindSpunk »

yakkers wrote: post #316
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…

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 option…

Huh, interesting. I had thought it was just from the higher gears being used. Vast majority of my driving is with manual, I've only really driven modern autos with 5+ gears (and a Toyota hybrid, which don't really have gears at all).

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

#323

Post by rkomorn »

angulardragon03 wrote: post #257
PeterStuer wrote: post #230

On my non EV car I seldom use the break unless in an emergency or I have to come to a full stop. I always use the cruise control to decelerate and accelerate. Anyone else has that habit?

… how do you think the cruise control decelerates you? Is this a troll post?

Maybe this is different on cars newer than 2015 but I've never felt cruise control apply brakes.

At most, I've felt it shift down (on an automatic, obviously) to use engine braking while it was trying to reduce speed going downhill.

Any other time, it's only slowed down by coasting.

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

#325

Post by tzs »

SV_BubbleTime wrote: post #79
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.

Wow. Well, I like that the people that think like this also probably live I places where you are actually driving a coal powered car. Like the clowns in Hawaii that have extra subsidies for EVs… their power comes directly from burning crude oil. I’m an automotive EE, and and the truth about EVs is in a rush to push them out the door, the media and politicians have set the tech back at least a decade by pretending it…

> Like the clowns in Hawaii that have extra subsidies for EVs… their power comes directly from burning crude oil.

If all their electricity comes from burning crude oil than they'd get about the same amount of miles in an ICE by refining that oil to gasoline for the cars and an EV by burning the crude oil for electricity, distributing that over the grid to drivers to charge their EVs.

However, about 22% of Hawaii's electricity comes from solar, so the EVs will come out ahead.

Even if we ignore solar and assume the EVs only use electricity from burning crude oil, the crude oil fueled generators should be cleaner than ICE engines, so there would be a significant reduction in total green house gases and particulates.

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

#326

Post by mattlondon »

BHSPitMonkey wrote: post #89
altairprime wrote: post #39

Earlier quoted context omitted.

If all of us renters were forced to convert to electric there’d never be an open charger in any city again for the next five years, because no landlord will voluntarily afford that cost, and no municipal region can pass a ballot measure to afford that cost. California’s impending ban of combustion car sales hinges wholly on a magical DC-charging network that doesn’t exist in U.S. cities yet (i.e. at parking meters),…

Level 1 charging overnight on a standard 120V outlet, while not ideal, is surprisingly adequate. Granted, many people rely on street parking or otherwise don't have a parking spot that is right beside their dwelling, but for rented houses or complexes with private garages/parking areas the size of the lift isn't necessarily "get upgraded service and a bunch of 240V EVSE put in".

Same here. Got an EV before we got the proper 7KW charger installed in our house. We had an outdoor socket that the gardeners use for whatever and just have a "granny charger" hooked up to that which I think charges at perhaps 2KW (10A on a 240v UK plug).

We use perhaps 5% battery of our VW ID.3 on a typical day (school run, shops, visiting friends or whatever) so we just do an over-night top-up back to 80% maybe once a week when we get down to ~50%. Working surprisingly well - I am not sure I can be bothered to get the proper charger installed (which is annoying as I have already bought it and the cable for about £800 and its just sitting in my shed!)

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

#327

Post by originalvichy »

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.

You are an anomaly. The overwhelming majority of EV drivers say their tyres last very long.

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

#328

Post by agurk »

MindSpunk wrote: post #312
agurk wrote: post #253

Earlier quoted context omitted.

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.

On all the fuel injected engines I have owned there is a physical cable that controls the position of the throttle plate. There is an airflow mass sensor the other side of the plate to measure the amount of air and therefore how much fuel needs to be injected. So interestingly in these sort of engines you're really just controlling airflow to the engine rather than fuel/air mix like on one with a carburettor.

More modern engines have electronically controlled throttle plates, and this is definitely somewhere you could do something clever like you suggest - cutting fuel flow but also maximising airflow when there is zero throttle input.

I assume engine braking is generally considered a beneficial thing by manufacturers, but it could be fun to be able to customise the amount. Or do something like have the braking come on gently at first then harder. Maybe even try and have a linear or flat response curve vs. engine rpm.

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

#329

Post by mattlondon »

stouset wrote: post #50
jjayj wrote: post #33

Earlier quoted context omitted.

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?

Public EV chargers are pretty widespread nowadays. Not as much as gas chargers obviously, but for most people in the country if you don't have a way to charge at home it's not fundamentally that different from not having a gas pump at your house. Plus, most people can charge at home with an extension cord. It's not particularly fast, but you should be able to get 4-5 miles an hour. In the worst case scenario where yo…

> Not as much as gas chargers

In the UK at least, there are more EV chargers than gas/petrol stations: https://www.vertumotors.com/news/there-are-more-charging-poi...

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

#330

Post by originalvichy »

gnarlouse wrote: post #134

But they burn through tires much faster due to the battery packs. All that tire friction has to go somewhere right?

This can also be offset by better traction control. EV engines respond to it much faster.
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