Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Pollution from tire wear is worse than exhaust emissions?

emissionsanalytics.com

Post reply on HN
Print view View original

211–220 of 336 posts

Re: Pollution from tire wear is worse than exhaust emissions?

#211

Post by helsinkiandrew »

adrianmonk wrote: post #147
helsinkiandrew wrote: post #87

Presumably they meant 5.8 milligrams/km rather than grams - thats 290 grams over 50,000km. The following literature review(2014) mentions an estimate of 0.1-10% tyre wear becoming airborne - because the majority is relatively large particles: https://publications.jrc.ec.europa.eu/repository/bitstream/J...

They must have meant grams because that is the basis of their 1000X statistic. The other number is also single digit but is in milligrams. That doesn't mean they're right, but it's the only way I can interpret what they're saying.

But 4.5g/km implies 225kg after 50000 km which doesn’t seem possible. Something definitely smells fishy.

Re: Pollution from tire wear is worse than exhaust emissions?

#212

Post by cjensen »

mycall wrote: post #204
jessaustin wrote: post #199

Earlier quoted context omitted.

Not sure if this test was set up to measure this, but brake dust, which contains all sorts of noxious particles, is a huge component of automobile emissions. This probably doesn't answer your question, however, because brake pads themselves only weigh so much...

I thought brake pads use asbestos which contribute to the noxious particles. I do think Vehicle-to-vehicle communications will eventually minimize the all the chicken necking, evening out the traffic and thus less breaking.

Brake pads have not used asbestos in several decades.

Re: Pollution from tire wear is worse than exhaust emissions?

#213

Post by ehnto »

thethrowboat wrote: post #177
ratel wrote: post #164

Hold on: The claim is this: > "Using a popular family hatchback running on brand new, correctly inflated tyres, we found that the car emitted 5.8 grams per kilometer of particles." It does not seem to be a mistake: > "Compared with regulated exhaust emission limits of 4.5 milligrams per kilometer, the completely unregulated tyre wear emission is higher by a factor of over 1,000." A tire might way up to 15 kilograms f…

"Non-exhaust emissions (NEE) are particles released into the air from brake wear, tyre wear, road surface wear and resuspension of road dust during on-road vehicle usage."

Roads are filthy. Cody's Lab once did a video where he collected road dust from the side of a highway, and refined out all the precious metals from it. That's from one small section of highway, just imagine the scale of the pollution across the whole of the states. Concrete dust, rubber, metals, fuel, oil. Cars and car infrastructure is dirty business.

https://www.youtube.com/watch?v=v5GPWJPLcHg

Re: Pollution from tire wear is worse than exhaust emissions?

#214

Post by pmiller2 »

dragontamer wrote: post #125
read_if_gay_ wrote: post #113

Earlier quoted context omitted.

You are missing that the cost of bike lanes isn't just in constructing and maintaining them. Adding bike lanes in cities means dropping car lanes because there's not enough space. That ends up creating potentially huge opportunity costs.

Not quite IMO. Anyone who has done any amount of virtual traffic engineering (aka: Factorio, City Skylines, OpenTTD) knows that intersections are where the bottlenecks are. Its incredibly difficult to design a max-throughput intersection. Roads have a huge amount of throughput, most "traffic" just gets stuck at offramps and traffic lights. Narrowing a road to make room for bike lanes is a lower cost than people might…

It’s not all about throughput. Taking away car lanes in favor of bike lanes usually takes away parking as well.

While that certainly has the desired effect of reducing car traffic to the area, it also increases the difficulty and expense of travel to the area. We’re seeing this in Oakland now, where they’re putting in bike lanes and taking away parking, while simultaneously doing nothing about the limited public transportation system.

If you want to reduce vehicle traffic without seriously impacting the shops and restaurants in the area, you have to use both knobs available to increase people’s use of public transportation: make it harder and more expensive to drive a car, while also making it easier (and, preferably, cheaper as well) to take transit. One without the other is a disaster.

Re: Pollution from tire wear is worse than exhaust emissions?

#215

Post by pmiller2 »

pedrosorio wrote: post #210
Marsymars wrote: post #191

Earlier quoted context omitted.

Depends. My commute home from my office has a 6km of a three-lane road and then a single traffic light. The road never gets backed up more than a couple km from the traffic light, so even dropping it to a single lane wouldn't make any real difference to the throughput. The speed you drive on the three-lane road also makes no real difference to the throughput as long as you get the same amount of cars through the traf…

> as long as you get the same amount of cars through the traffic light at each cycle. Isn’t this proportional to the number of lanes in the road?

If all the lanes are used at capacity, yes. Otherwise, no.

Re: Pollution from tire wear is worse than exhaust emissions?

#216

Post by bryanmgreen »

All these articles are important, but they end up missing the point of the auto industries weightiest concern.

At the end of the day, it really comes down to the weight of the vehicles. There is absolutely zero justification for any standard-use car to weigh more than 3,200 pounds, and that's for a SUV.

More weight affects EVERYTHING.

Material logistics/sourcing/shipping/construction costs and emissions/waste-disposal, end-product shipping/distribution/operating-costs and emissions/repairs/waste-disposal, as well as infrastructure construction/maintenance. That's just hard costs. I could go on in more granular fashion and add soft costs like less traffic and less road noise as well.

I drive a very loaded gasoline powered Fiesta hatchback. It's got cruise control, a great entertainment system with car play, even stupid neon lighting I didn't want. It weighs only 2,600 pounds and even though it isn't fast, I don't have any issues getting up to speed. My mileage is consistently 29 in LA traffic and 34 driving fast on long highway trips. It's nearly 2 feet (22 inches!!) shorter than a Camry and I can park it basically anywhere. Because it weighs so little, tires last forever. It cost me less than $20,000 brand new. My point is that a freaking heavy and large 3,400lb sedan, or 4,500lb SUV is 100% supremely unnecessary.

Multiply hundreds or thousands of weight savings per-car over millions and millions of new cars sold in the US alone would insanely positive and tangential effects on the planet. Eventually those gains would reach the economy and infrastructure too.

It just infuriates me that there is a relatively simple way to mitigate so many issues and it's so blatantly ignored or not even known.

Re: Pollution from tire wear is worse than exhaust emissions?

#217

Post by jessaustin »

cjensen wrote: post #212
mycall wrote: post #204

Earlier quoted context omitted.

I thought brake pads use asbestos which contribute to the noxious particles. I do think Vehicle-to-vehicle communications will eventually minimize the all the chicken necking, evening out the traffic and thus less breaking.

Brake pads have not used asbestos in several decades.

New pads on new passenger vehicles haven't, but it's still legal to use asbestos in aftermarket pads.

https://parts.olathetoyota.com/what-are-brake-pads-made-of

Re: Pollution from tire wear is worse than exhaust emissions?

#218

Post by cormacrelf »

_rrnv wrote: post #181
sschueller wrote: post #172

Earlier quoted context omitted.

Most of it must come from the asphalt.

I agree. But tires do shed a lot. Consider a brand new tire has grove depth of about 8-10mm, and many drivers change tires when their groves are 0-2mm (yes, some idiots keep driving until they have slicks or "a pop").

Turns out you don’t need to measure air pollutants, you can just divide lost rubber by the distance travelled. It won’t be anywhere close to what was measured, but then again actual particles are a much more useful number because you can’t breathe a worn down groove.

Re: Pollution from tire wear is worse than exhaust emissions?

#219

Post by gok »

_Microft wrote: post #32

Maybe offtopic but a surprising bit of extra information regarding wear and vehicles: Road wear scales with the fourth power of axle load, so heavier vehicles do much more damage than one might expect. Take a 40t truck with 5 axles vs. a small car with a weight of 1t and two axles (e.g. VW Polo, maybe an older VW Golf might only weigh 1t as well): (8t axle load / 0.5t axle load) = 16^4, i.e. the truck puts 2^16 (6553…

Suggests we should ban buses.

Re: Pollution from tire wear is worse than exhaust emissions?

#220

Post by spaginal »

bryanmgreen wrote: post #216

All these articles are important, but they end up missing the point of the auto industries weightiest concern. At the end of the day, it really comes down to the weight of the vehicles. There is absolutely zero justification for any standard-use car to weigh more than 3,200 pounds, and that's for a SUV. More weight affects EVERYTHING. Material logistics/sourcing/shipping/construction costs and emissions/waste-disposa…

Unnecessary for you and your usage, but there a lot of situations, environments, and applications where a heavier, larger vehicle is necessary. If you live rural you aren't driving a small Fiesta hatchback everywhere. If you have a large family, an SUV is a basic requirement of modern living to move the family around.

Conversely if you live in a city with tight quarters as a single person with no kids, an SUV or pickup may not be necessary at all.

There is a reason we don't dictate choice or consumption with something as necessary and basic as transportation because it isn't one size fits all. People buy what they generally need.

Post reply on HN