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by nordsieck 330 days ago
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.
2 comments
tonymet 330 days ago
They address this briefly in the article (though inadequately) , that tire particles are heavier and doesn’t end up in the air like brake dust.

But you do raise a good point at the holistic condition, and assessing a broader population with less than ideal configuration.

They are looking at lightweight EVs at lower speeds. But Americans drive heavier EVs at highway speeds. The rotors & pads are huge.

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pdabbadabba 330 days ago
> They are looking at lightweight EVs at lower speeds. But Americans drive heavier EVs at highway speeds. The rotors & pads are huge.

Perhaps other EV drivers can chime in but, if anything, I think I use my friction brakes less at highway speeds where, in general, you're not really supposed to do a lot of braking. I'd say, overall and regardless of speed, my friction brakes are really used only to bring the car to a complete stop or for emergency braking to avoid a potential accident.

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nordsieck 330 days ago
> Perhaps other EV drivers can chime in but, if anything, I think I use my friction brakes less at highway speeds where, in general, you're not really supposed to do a lot of braking. I'd say, overall and regardless of speed, my friction brakes are really used only to bring the car to a complete stop or for emergency braking to avoid a potential accident.

Some people are very responsible with money - they have an emergency fund, contribute to their retirement fund, and don't carry a credit card balance.

Other people (who have a choice) spend to 0 every month, don't save, and have maxed out credit cards.

In the same way, some people drive very safely; they keep a responsible distance between them and the driver in front of them, and don't tend to speed much. I think this style of driving would naturally lead to what you say - less use of friction breaks in general, and especially at highway speeds.

And other people are constantly speeding, and tailgate the person in front of them when their path is blocked. For the people who drive this way, the greater acceleration of EVs just lets them drive that much more recklessly. Which ends up necessitating even more usage of friction brakes.

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tonymet 330 days ago
I'm one of the chill EV drivers too. but imagine the distribution over vehicles that are 30-75% heavier, and the range of drivers from chill to agro (leaning toward agro), and you can see the benefits and costs start to cancel out.

I still expect EVs to be a net improvement on brake dust. just not as massive as the study. maybe about 1/2 - 1/3 of the study's results

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D13Fd 330 days ago
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.
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janosch_123 330 days ago
Not sure about that. If you accelerate a 2t vehicle to 60mph and then decelerate it back to 0mph then they would stress the tyres in the same way, no matter if you do EV & regen, EV no-regen or ICE, right? (I am keeping the weight constant).

Prompted by your comment I had a look at vehicle weights and two facts stood out

- ALL new cars are getting heavier EVERY YEAR because we keep adding more stuff (average car weight, and average SUV weight trend upwards from 2016 to 2023)

- The average electric car is heavier than a petrol equivalent but is lighter than an SUV

Weight certainly a problem, but the focus on EVs for weight is generally blown out of proportion.

https://www.thisismoney.co.uk/money/cars/article-13588773/Ne... https://www.sustainabilitybynumbers.com/p/weighty-issue-of-e...

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