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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

#271

Post by pkolaczk »

cperciva wrote: post #176
nine_k wrote: post #41

I suppose the same should apply to hybrid cars, which outnumber pure EVs significantly [1]. The effect comes from converting the kinetic energy back to the battery charge via generation instead of wasting it via friction, which is the whole point of hybrids. [1]: https://www.consumeraffairs.com/automotive/how-many-electric...

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.

Another part of the point is that you can pack a much smaller and more efficient ICE and then substitute the missing power and torque from electric motors when needed. Most cars are not used at max power all the time. You need max power only at short times when accelerating. With pure ICE there is the tradeoff - a bigger engine will get you more max power / max torque but is going to be less fuel efficient because of internal friction.

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

#272

Post by defrost »

MindSpunk wrote: post #248
defrost wrote: post #147

Earlier quoted context omitted.

> if they've already been plugged once and theu get another puncture its off to the bin. Again, that's your personal choice. We've got off road and on road tyres we still use with four to five tyre plugs in them that have lasted a few years since their last puncture. I'm in non urban Australia and have cars actively used with > 500,000 km on the clock. We were raised to maintain gear; be it cars, trucks, aircraft, ex…

It's a choice in so much as I would be gambling against how likely I am to get knocked back at a safety inspection for having plugs on the side wall. I'm in urban NSW and whether I'd get by a safety inspection would be a gamble on how particular the mechanic is. One of the mechanics I go to warned me about a single slightly cloudy headlight for my next inspection, which is comical compared to some of the cars I've se…

I didn't advocate sidewall plugs.

What I can say is that properly fitted plugs in the tread can last a long time with little leakage and that three or four plugs in the tyre tread (widely spaced, not all jammed in a big hole) seem to last a fair few years.

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

#273

Post by ben-schaaf »

unglaublich wrote: post #214
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.

This is how diesel-electric locomotives work too.

They also use the electric motor(s) for braking, but instead of going into a battery it goes into a bank of resistors.

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

#274

Post by pkolaczk »

fho wrote: post #184
nine_k wrote: post #41

I suppose the same should apply to hybrid cars, which outnumber pure EVs significantly [1]. The effect comes from converting the kinetic energy back to the battery charge via generation instead of wasting it via friction, which is the whole point of hybrids. [1]: https://www.consumeraffairs.com/automotive/how-many-electric...

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.

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

#275

Post by _fizz_buzz_ »

altairprime wrote: post #39
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.

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),…

It's really not as big of deal anymore. My co-worker got an electric car and has his own house with a garage and never ended up installing a wall box. He simply charges at work or while buying groceries.

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

#277

Post by pkolaczk »

Helmut10001 wrote: post #124
dyselon wrote: post #99

Earlier quoted context omitted.

We finally gave up our Prius after 12 years, and we never changed the brakes once. The brakes were just peeking into the yellow on its last service upgrade. I was really impressed with how well the "normal" hybrid could take advantage of regenerative breaking, honestly.

I first changed the brakes on my Mitsubishi Space Star (combustion) after 13 years. It is a small car, less than 1000kg, so there is little for the brakes to do. If we produced more percentage of small cars, many environmental risks would be reduced. And btw.: The tires are now 19 years old and still good (less weight, less abrasion!).

Seriously, you should not use tires older than 10 years. They degrade over time.

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

#278

Post by mort96 »

pkolaczk wrote: post #271
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.

Another part of the point is that you can pack a much smaller and more efficient ICE and then substitute the missing power and torque from electric motors when needed. Most cars are not used at max power all the time. You need max power only at short times when accelerating. With pure ICE there is the tradeoff - a bigger engine will get you more max power / max torque but is going to be less fuel efficient because of…

And, you can make much lighter and lower range electric cars without all those heavy batteries, and boost the range with diesel when needed. Very attractive in principle. Most cars are not using their full range all the time, for a lot of people a 50 mile range car would be more than enough 98% of the time, but that remaining 2% means that people end up buying 200 mile range cars instead.

But then, do you end up removing enough battery weight to offset the weight of a whole ICE?

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

#279

Post by ddeck »

federiconafria wrote: post #265
masklinn wrote: post #264

Earlier quoted context omitted.

Afaik that’s pure series hybrid and that’s almost non-existent in cars (outside of range extenders, not that there are that many of those). There are a handful but most hybrids are either parallel or series-parallel. I assume because the power range is so low that the conversion losses are way too noticeable compared to a mechanical drivetrain.

That's something I wish there had been more focus on, instead of focusing on massive heavy batteries, develop the hybrids further.

Not sure about the US, but the Japanese didn't stop focusing on hybrid development. More than half of all sales in Japan are hybrids, whereas electric is only a few percent [1].

Honda even recently announced that they're scaling back on electric to focus on hybrids:

https://www.reuters.com/business/autos-transportation/japans...

[1] https://www.bloomberg.com/news/articles/2023-12-19/hybrid-ca...

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

#280

Post by ddeck »

ben-schaaf wrote: post #273
unglaublich wrote: post #214

Earlier quoted context omitted.

This is how diesel-electric locomotives work too.

They also use the electric motor(s) for braking, but instead of going into a battery it goes into a bank of resistors.

I think you meant capacitors. Resistors would just dissipate the energy as heat.

edit: Thanks for the correction. They do indeed use resistors and just dump the energy as heat. Unfortunate.

Hopefully this will change as supercaps continue to improve. Maxwell tech's modules are already used in light rail, and looks like some work towards smaller locomotives in Switzerland here:

https://www.osti.gov/etdeweb/servlets/purl/20823697

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