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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

#571

Post by thmsths »

eftpotrm wrote: post #414
throw0101d wrote: post #363

Earlier quoted context omitted.

> […] but there can also be a significant benefit from allowing the ICE to remain in the RPM "sweet spot" rather than moving around a larger range. Which is why I'm surprised electric cars with range extenders aren't a bigger thing: * https://en.wikipedia.org/wiki/Range_extender Have the powertrain be all-electric, and have a battery pack, but for those with range anxiety have a small generator as an option that woul…

BMW tried that with the i3, it wasn't particularly popular. An engine, fuel system and a generator are all relatively complex additions compared to just putting the same cost and vehicle space into more batteries, and the public charging networks are definitely up to the task by now (having been EV-only for almost 5 years now).

I've ridden in one and this was basically a case of "you get the worst of both worlds". The engine was small and running at a constant RPM, leading to an annoying noise in the cabin. The range extension was not particularly huge. Worse, when we did eventually run out of battery on one trip, the range extender was unable to recharge the battery after refueling the car, forcing us to scramble to find an available charging station with the car on the tow truck...

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

#572

Post by frollogaston »

mort96 wrote: post #282
dotancohen wrote: post #203

Earlier quoted context omitted.

And that downshifting involves a clutch operation, moving the engine into a higher RPM. That most certainly wears down the clutch, talking as someone who's replaced quite a few of them.

I didn't quite get if you think changing gears for the purpose of engine braking wears the clutch more than normal or not. Are you using the force from the clutch to force the engine to go from a low RPM to a high RPM? In cases like that where the difference in RPM is significant, I would press the clutch pedal, then speed up the engine by pressing the gas pedal, downshift, then release the clutch. Rev matching, basi…

You might not execute the rev-match perfectly every time, esp if you're doing a heel-toe. I think it's also harder on the synchro.

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

#573

Post by HPsquared »

RegnisGnaw wrote: post #534
theshrike79 wrote: post #397

Earlier quoted context omitted.

This is the thing with good hybrids. The "gas pedal" becomes a "I want to go faster/slower" pedal, its position has zero impact on the RPM. As an anecdote: A security company I know only buys Toyota Hybrids for their guards just because of that. They have a habit of driving cars like they stole them and normal ICE cars break down from that kind of abuse. Hybrids won't let you abuse them, they pick the RPM and you dea…

The whole "pas pedal" becomes faster/slower (one pedal driving) is coming to an end. Its being banned as default in the world's largest EV market (and largest EV export country).

Huh, that's interesting. Apparently China will be banning cars from having one-pedal driving as the default.

Losing muscle memory of pressing the brake pedal. Makes sense, actually.

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

#574

Post by frollogaston »

beau_g wrote: post #221
dotancohen wrote: post #203

Earlier quoted context omitted.

And that downshifting involves a clutch operation, moving the engine into a higher RPM. That most certainly wears down the clutch, talking as someone who's replaced quite a few of them.

I've seen an interesting A-B test with this seeing the difference in clutch wear between the Ferrari F1 transmission in the 599 and 612 and the DuoSelect transmission which is essentially the same box in the Quattroporte. The shifting strategy and technique is more of a controlled variable here because the shifting is automatic though it's a somewhat traditional manual gearbox with hydraulic actuation. The QP is a bi…

I semi-daily drive a DuoSelect Quattroporte, but usually in light traffic. The clutch-eating problem is sorta inherent to the car. First off, it uses extra clutch to smooth out shifts in non-sport mode, and you don't always want sport mode because it stiffens the suspension a lot. But even in sport, you can't always get it to behave predictably. So given an experienced driver with both cars in city traffic, the DuoSelect will eat clutch faster than a stick. Some install an aftermarket box (Formula Dynamics) to improve this, but still.

Idk how the Ferraris are different. They're lighter at least. Think they also have a different version of the "Superfast" software.

Anyway... I do engine-brake it. The real brakes appreciate not having to stop that limo by themselves.

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

#575

Post by quickthrowman »

throw0101d wrote: post #363
cperciva wrote: post #176

Earlier quoted context omitted.

which is the whole point of hybrids Part of the point, not the whole point. Regenerative breaking is absolutely a win; but there can also be a significant benefit from allowing the ICE to remain in the RPM "sweet spot" rather than moving around a larger range.

> […] but there can also be a significant benefit from allowing the ICE to remain in the RPM "sweet spot" rather than moving around a larger range. Which is why I'm surprised electric cars with range extenders aren't a bigger thing: * https://en.wikipedia.org/wiki/Range_extender Have the powertrain be all-electric, and have a battery pack, but for those with range anxiety have a small generator as an option that woul…

One 120V 2.2kW generator isn’t going do much at all. It’s really actually 1.8kW which is 15A at 120V.

You’d need to tow around a 7.2kW 240V for 30A at 240V (more likely a 14.4kW generator for 240V 60A).

Using the small Honda inverter generator (which is amazing for plenty of stuff!) is akin to covering your car in solar panels to get range extension, the math just doesn’t work out.

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

#576

Post by silverquiet »

happyPersonR wrote: post #402
pmg101 wrote: post #349

Earlier quoted context omitted.

I thought about PHEV but in the end went full EV simply because it seemed to me with two whole power trains that's 2x the components to go wrong/need maintenance.

This. This times 100x . Also, it’s not like each powertrain has an independent failure mode. If either break, your car is a brick until it’s fixed.

I have a friend who drives a Chevy Volt with a dead ICE engine; she just charges the battery and uses it as a (rather short range) pure EV vehicle. Not ideal, but it works for her until she gets something else.

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

#577

Post by D13Fd »

nordsieck wrote: post #567

From what I've heard there's a countervailing effect for EVs, though - they end up generating more particulate pollution from tire wear because of greater vehicle weight and greater torque. The number that I've seen bandied about is ~20% greater tire wear.

That was my first thought. Fewer brake particles is great, but I’m guessing it won’t be enough to counter the increased tire wear.

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

#578

Post by NewJazz »

slt2021 wrote: post #517
NewJazz wrote: post #177

Earlier quoted context omitted.

most of the tire wear happens when car decelerates Is this generally true? I imagine it depends on the car/driver to a certain extent, but still I'd be curious what numbers are out there.

when car decelerates, the kinetic energy has to go somewhere, large part of it goes to battery as regeneration (60%), the rest goes to tire/road friction and wear

That doesn't answer my question even a little bit.

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

#579

Post by silverquiet »

eldaisfish wrote: post #492
potato3732842 wrote: post #444

Earlier quoted context omitted.

"Everyone who doesn't want what I want them to want has been brainwashed by corporate interests" is not a robust assertion under even the most casual scrutiny. I hate to break it to you but something like a Rogue or HRV does circles around an Altima or Civic when it comes to daily flexibility and utility for a fairly paltry additional cost. It doesn't take a degree in rocket surgery to figure out why they fly off the…

The North American market now only includes a handful of sedans. Meanwhile, Hyundai and Toyota somehow manage to sell “tiny” cars in Korea, Japan and lots of developing countries. A practical car is a station wagon, not an SUV, many of which have less storage space. Please, cut the needless snark. People do buy vehicles for edge cases but the lack of smaller, practical vehicles is driven is large part by manufacturer…

I think the crossover is pretty much the modern station wagon. I suppose they get marketed as SUV's but they're basically just a bit longer and taller car vs what I'd consider a "real" SUV; an enclosed truck chassis.

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

#580

Post by tonymet »

You can get similar results with proper deceleration, engine braking and downshifting. I’ve had brake pads last 110k miles (with room for 20k+ more), even though I lived in moderate hilly area. That’s probably 1/3 the brake dust, and comparable to an EV .

If you are getting lower MPG than the EPA rating, you are also burning up your brakes from heavy deceleration. Improve your MPG to 15% over EPA and your brakes will last a lot longer.

Also their studies were in European markets with tiny EVs and low speeds. Americans are favoring 7k-9k lb EVs (Hummer, Rivian), with massive brake rotors and PADs— at highway speeds 75mph+. A good driver of a 3k lb vehicle will produce less brake dust than a typical driver of a 9k EV.

Studies like this are helpful, but they are not comprehensive. Similar to the marketing that home LEDs would have 10-20 year longevity, yet in practice they burn out after a few years. The full supply and application chain has to align for the ideal results in practice.

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