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by superqwert 2912 days ago
how will they reduce braking dust? I thought they were primarily only going to use the brake power for energy.
6 comments

> how will they reduce braking dust?

"In urban environments, brake wear can contribute up to 55 % by mass to total non-exhaust traffic-related PM10 emissions" [1]. (The "abrasion processes which result in direct particulate matter (PM) emission are tyre, brake, clutch and road surface wear, with other potential sources being engine wear, abrasion of wheel bearings and corrosion of other vehicle components, street furniture and crash barriers.")

When a vehicle regeneratively brakes, the brakes aren't engaged. Instead, the transmission connects to a generator, which resists the vehicle's motion as it converts kinetic energy into electricity.

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4315878/

Braking dust comes from brake pads rubbing against brake disks. Electric vehicles slow down by running the motor in reverse and recharging the battery, therefore don't use the brake pads and brake disks as much, especially at higher speeds where the brake dust problem is the worst.
Using the engine for braking means the physical brake will not be used, so there will be no dust in that case.
Regenerative braking is using the electric motor as a generator for a time during braking. So you're not dealing with pads and rotors wearing down, at least not as much.
You need your braking pads less when you convert the kinetic energy in electricity.
Thanks for that, all