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A comment on Students create device to capture car tyre microplastic debris. Parent comment

Re:Students create device to capture car tyre microplastic d... by nwah1 on Sunday November 29, 2020 @05:02PM (#25248504)
EVs actually make this problem worse because they are heavier. Both brakes and tires release toxic pollution.

While I fully admit that these are all engineering challenges that people could make progress on, there's also much simpler and more immediately actionable ways to improve this situation. Like encouraging walkable neighborhoods.

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Re:Students create device to capture car tyre microplastic d... by Thlom on Sunday November 29, 2020 @05:06PM (#25248534)
EVs don’t actually use the brakes much as they often have very aggressive regeneration. Rust on underused brakes is a problem on my EV at least. :-)
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Re:Students create device to capture car tyre microplastic d... by Retric on Sunday November 29, 2020 @05:19PM (#25248620)
Also, while I can see various synthetic tires being an issue, is vulcanized natural rubber actually a problem? It’s starting off as tiny particles which should degrade fairly quickly.
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Re:Students create device to capture car tyre microplastic d... by PaulDavisThe1st on Sunday November 29, 2020 @05:46PM (#25248802)
From HN earlier today: https://www.hakaimagazine.com/features/when-rubber-hits-the-...
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Re:Students create device to capture car tyre microplastic d... by Retric on Sunday November 29, 2020 @07:26PM (#25249482)
The finished product isn’t considered toxic, but some individual ingredients are, including heavy metals like cadmium and lead, and high aromatic oils (more commonly known as polycyclic aromatic hydrocarbons or PAHs)

So, presumably non synthetic tires are actually fine. Though, it’s not clear if that was the intent of the article.

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Re:Students create device to capture car tyre microplastic d... by artvark11 on Monday November 30, 2020 @01:03PM (#25256795)
Could you explain how the rust is causing an issue on your brakes? Siezed piston or pin?
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Re:Students create device to capture car tyre microplastic d... by Thlom on Thursday December 03, 2020 @02:55AM (#25286632)
It's the brake disc. Some rust on the surface is not a big problem, but if it starts digging in to the metal mass it will cause reduced brake capacity. In Europe a car with lots of rust on the brake disc will not be certified for use (mandatory checkup every two years) until the brake discs have been replaced.
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Re:Students create device to capture car tyre microplastic d... by nwah1 on Sunday November 29, 2020 @05:46PM (#25248799)
Regenerative brakes rely on friction just like any other. Pollution is a given.
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Re:Students create device to capture car tyre microplastic d... by klyrs on Sunday November 29, 2020 @05:59PM (#25248882)
Regenerative brakes translate kinetic energy into stored potential energy, with marginal friction and resistive losses. Friction brakes translate 100% of the kinetic energy into waste heat, through abrasion.

While it's true that regenerative brakes are not frictionless, none that I'm aware of rely on friction. One could imagine using a clutch to controllably wind/unwind a spring, for example, but auto manufacturers aren't rinky-dink steampunkers and even so you'd still do everything you could to minimize clutch slippage.

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Re:Students create device to capture car tyre microplastic d... by magicalhippo on Sunday November 29, 2020 @06:22PM (#25249060)
> While it's true that regenerative brakes are not frictionless, none that I'm aware of rely on friction.

They rely on the friction between the tire and the road, wearing the tire down, releasing the microplastic particles.

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Re:Students create device to capture car tyre microplastic d... by chrisseaton on Sunday November 29, 2020 @07:02PM (#25249326)
> They rely on the friction between the tire and the road

I don't think the tire is what people mean when they talk about the brakes. They mean the brake pads and other brake components.

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Re:Students create device to capture car tyre microplastic d... by jeddy3 on Monday November 30, 2020 @03:42AM (#25251895)
It's literally what the linked article talks about, tyre wear not break wear.
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Re:Students create device to capture car tyre microplastic d... by chrisseaton on Monday November 30, 2020 @04:51AM (#25252248)
This thread started when someone said ‘both brakes and tyres emit pollution’. The point was the brakes don’t when they’re regenerative. I’m sure the tyres still do. But that wasn’t what the thread was about.
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Re:Students create device to capture car tyre microplastic d... by chrisseaton on Sunday November 29, 2020 @06:02PM (#25248906)
> Regenerative brakes rely on friction just like any other.

I thought the resistance was provided by magnets in the motor? How do you think they capturing energy from friction?

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Re:Students create device to capture car tyre microplastic d... by durkie on Sunday November 29, 2020 @05:58PM (#25248872)
What friction? The "regenerative" part is from the motors being driven in reverse and returning power to the battery.
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Re:Students create device to capture car tyre microplastic d... by nitrogen on Sunday November 29, 2020 @06:17PM (#25249029)
Rolling friction in the tires / the contact patch's static friction.
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Re:Students create device to capture car tyre microplastic d... by culopatin on Sunday November 29, 2020 @07:31PM (#25249519)
This variable is a constant between both types of brakes. How is this relevant when comparing brakes? They both need it, one puts energy into a battery, the other one just heats up air due to the friction created by the system.
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Re:Students create device to capture car tyre microplastic d... by nitrogen on Sunday November 29, 2020 @09:41PM (#25250243)
It's relevant to the question of whether regenerative braking produces dust from tire wear.
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Re:Students create device to capture car tyre microplastic d... by TheGallopedHigh on Monday November 30, 2020 @02:25AM (#25251470)
As compared to just straight braking — hence it’s irrelevant
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Re:Students create device to capture car tyre microplastic d... by nitrogen on Monday November 30, 2020 @04:14AM (#25252055)
The whole thread started with this message:

> Regenerative brakes rely on friction just like any other. Pollution is a given.

The article is about pollution from tires. Regenerative breaking can't cheat the laws of physics. That force has to be applied to the road through tires, just like any other form of wheel braking. And tires have significantly more mass to shed over their lives than brake pads.

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Re:Students create device to capture car tyre microplastic d... by Hnrobert42 on Sunday November 29, 2020 @10:28PM (#25250453)
How about both? Why frame it as either/or?
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