Live data from Hacker News

Dust from car brakes more harmful than exhaust, study finds

e360.yale.edu

71–80 of 465 posts

Re: Dust from car brakes more harmful than exhaust, study finds

#71

I think this is missing out on the big issue - tyre pollution which contains really nasty chemicals that inevitably get washed into rivers and waterways. Also, car-shaped EVs often use regenerative braking which will reduce the amount of brake dust pollution, but with their increased weight and powerful torque, they produce a lot more tyre pollution than ICE vehicles. https://earth.org/tyre-pollution/

Interesting that nobody every talked about tyre/brake dust until it became clear that cars aren't going away as we phase out fossil fuels, they're just going electric. Is this a serious environmental concern compared to the climate/emissions issue, or just the 'r/fuckcars mentality'? Meanwhile, here in the UK, one of the more interesting alternatives - personal light EVs (ebikes/scooters) are being utterly demonized,…

Firstly, this is another positive for EVs. They do have brakes but most have regenerative braking too, which is clean.

Secondly, ebikes are rampantly misused in pedestrian areas, often used without helmets, often upclocked, many used for delivering, or kids. And because they're not a regulated vehicle, nobody has third party insurance.

There are legal ebikes and nobody has any more of a problem with them than normal bicycles when used in the right places.

Re: Dust from car brakes more harmful than exhaust, study finds

#72

I think this is missing out on the big issue - tyre pollution which contains really nasty chemicals that inevitably get washed into rivers and waterways. Also, car-shaped EVs often use regenerative braking which will reduce the amount of brake dust pollution, but with their increased weight and powerful torque, they produce a lot more tyre pollution than ICE vehicles. https://earth.org/tyre-pollution/

Interesting that nobody every talked about tyre/brake dust until it became clear that cars aren't going away as we phase out fossil fuels, they're just going electric. Is this a serious environmental concern compared to the climate/emissions issue, or just the 'r/fuckcars mentality'? Meanwhile, here in the UK, one of the more interesting alternatives - personal light EVs (ebikes/scooters) are being utterly demonized,…

I looked into this in detail a while ago [1]. Electric cars produce much less brake pollution than traditional cars due to regenerative braking. They do probably create more tire pollution, simply because batteries are heavy. And, current emission standards for gasoline engines are so strict (and engines so well designed) that the engines themselves probably do create a negligible fraction of the overall particulate pollution. So it's plausible that with current technology, hybrid cars might create the least total particulate pollution. But all electric cars are probably better than all-gasoline cars.

That said, I'd think we could probably do lots more to reduce the tire pollution. And, obviously, electric cars have other advantages!

[1] https://dynomight.net/tires/

Re: Dust from car brakes more harmful than exhaust, study finds

#73
post #52

This is the regular current taboo. Micro-dust from tires and brakes contributes to half of an ICE vehicle’s pollution, with the other half coming from exhaust emissions. The amount of this micro-dust scales with a power of the vehicle’s weight, typically between the square and cube for cars, and up to the fourth power for heavy trucks. EVs are 30–60% heavier than their ICE counterparts. Assuming all other factors rem…

[deleted]

Re: Dust from car brakes more harmful than exhaust, study finds

#74
post #52

This is the regular current taboo. Micro-dust from tires and brakes contributes to half of an ICE vehicle’s pollution, with the other half coming from exhaust emissions. The amount of this micro-dust scales with a power of the vehicle’s weight, typically between the square and cube for cars, and up to the fourth power for heavy trucks. EVs are 30–60% heavier than their ICE counterparts. Assuming all other factors rem…

All other factors arent constant though: EVs use their brakes much less.

They have slimmer tires as well, right? I wonder though, do they deteriorate faster as their surface would carry more weight?

edit: https://earth.org/tyre-pollution/ answers this, as mentioned elsewhere in this thread.

Re: Dust from car brakes more harmful than exhaust, study finds

#75
post #52

This is the regular current taboo. Micro-dust from tires and brakes contributes to half of an ICE vehicle’s pollution, with the other half coming from exhaust emissions. The amount of this micro-dust scales with a power of the vehicle’s weight, typically between the square and cube for cars, and up to the fourth power for heavy trucks. EVs are 30–60% heavier than their ICE counterparts. Assuming all other factors rem…

EVs are heavier than similar ICE vehicles, but they also have regenerative braking, which greatly reduces wear on the brake pads. I suspect EVs produce much less particulate pollution from brake pads, but somewhat more from their tires.

Re: Dust from car brakes more harmful than exhaust, study finds

#76
post #49

Earlier quoted context omitted.

You show me one of these that can be ridden [comfortably] in 2 degrees Fahrenheit with snow and ice everywhere and you have my money!

Or by people who are disabled/elderly. I have MS, cycling isn't really going to work on a regular basis because between heat intolerance and cold making my leg spasticity worse, I'm not going to have a good time. I can drive just fine, though. While yes, a lot of the elderly continue to cycle in countries where the infrastructure exists (e.g. the Netherlands), those places also have universal healthcare. You can't ju…

In cities such as Copenhagen, it's very common to see parents transporting small children (and a large number of pets from what I saw) using cargo-bikes.

Not having universal healthcare seems like a strange argument against active travel as it's well known that active travel can drastically improve people's health and reduce the need for healthcare - it would seem more important to choose to look after your health if you can't rely on healthcare being available if you lose your job etc.

Your disability point is perfectly valid, although some disabilities make it easier to cycle than to walk. However, if we can get as many able-bodied people to use active travel when feasible, it'll clear vehicles from the roads and make it easier for the people that rely on their cars for mobility.

Re: Dust from car brakes more harmful than exhaust, study finds

#77

Earlier quoted context omitted.

I think the key is to make a class of light-weight EVs with smaller, lighter batteries for life around town. Most of us rarely drive more than a few dozen miles a day. But then there are those weekend trips.

For the weekend trips you could put in an engine with a power splitter Oh what's this, turns out the ideal car was already invented twenty years ago, it's the Toyota Prius Casually gets 50 mpg city and highway Small, lightweight battery Not a super expensive status symbol The plugin models use very little gas for the daily commute, but you can always drive it like a pure ice car if you need to flee the country on zer…

The Volt was a much better idea. It could be an all electric car—at any speed—for 50 miles or so.

Re: Dust from car brakes more harmful than exhaust, study finds

#78

I think this is missing out on the big issue - tyre pollution which contains really nasty chemicals that inevitably get washed into rivers and waterways. Also, car-shaped EVs often use regenerative braking which will reduce the amount of brake dust pollution, but with their increased weight and powerful torque, they produce a lot more tyre pollution than ICE vehicles. https://earth.org/tyre-pollution/

This is why a move to natural latex rubber tires is necessary. Companies have experimented with them[1][2] but a world-wide switchover should be in the works.

[1] https://www.continental-tires.com/about/sustainability/activ...

[2] https://arstechnica.com/cars/2023/04/eco-friendly-tires-brid...

Re: Dust from car brakes more harmful than exhaust, study finds

#79

Earlier quoted context omitted.

I think the key is to make a class of light-weight EVs with smaller, lighter batteries for life around town. Most of us rarely drive more than a few dozen miles a day. But then there are those weekend trips.

I'd love one of these as an electric commuter vehicle: https://pressroom.toyota.com/album/toyota-i-road/ Unfortunately it seems to have gone nowhere

A fair number of people do own bikes. But almost certainly the majority of people don't want to own a second vehicle--focused on transportation, rather than recreation--when they need/want a primary, probably ICE, vehicle anyway.

Re: Dust from car brakes more harmful than exhaust, study finds

#80
post #52

This is the regular current taboo. Micro-dust from tires and brakes contributes to half of an ICE vehicle’s pollution, with the other half coming from exhaust emissions. The amount of this micro-dust scales with a power of the vehicle’s weight, typically between the square and cube for cars, and up to the fourth power for heavy trucks. EVs are 30–60% heavier than their ICE counterparts. Assuming all other factors rem…

"Assuming all other factors remain constant" is doing a lot of (largely unjustified) work there. Regen braking massively reduces the amount of friction-brake usage in EVs, to the point where brakes will need to be repaired due to under use.
Post reply on HN