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by nwah1 2031 days ago
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.

2 comments

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. :-)
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.
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.

Could you explain how the rust is causing an issue on your brakes? Siezed piston or pin?
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.
Regenerative brakes rely on friction just like any other. Pollution is a given.
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.

> 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.

> 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.

It's literally what the linked article talks about, tyre wear not break wear.
> 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?

What friction? The "regenerative" part is from the motors being driven in reverse and returning power to the battery.
Rolling friction in the tires / the contact patch's static friction.
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.
It's relevant to the question of whether regenerative braking produces dust from tire wear.
How about both? Why frame it as either/or?