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Pollution from tire wear is worse than exhaust emissions?

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

#221

Post by allovernow »

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…

Yep, I was going to say. I believe new tires may initially shed far material, the same way that they offgas for weeks.

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

#222

Post by saiya-jin »

kungtotte wrote: post #173
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…

They're torn up from the road and rubbed off from the tyres themselves. The majority is obviously coming from the road. There's been studies done here in Sweden since we've banned studded winter tyres in some areas of Stockholm in an effort to reduce road wear and improve air quality. I don't know of any sources in English off the top of my head though. The last time I read an article about it though (2+ years ago, d…

That doesn't make sense to me either. Take a busy German highway (as I don't know the average load on US ones), easily 100k cars per day. There are parts of highways which don't get replaced for 20 years easily. Plus apart from tiny fraction of north europe (and maybe Canada?), nobody ever uses studs.

Back of the envelope math tells me 1 km of highway would lose some 730 tonnes of asphalt, per year (so 14,600 tonnes in 20 years). If we talk about normal car wear, this simply isn't happening on those unkempt roads. It would leave huge lanes of deeper surface where asphalt is lacking. There isn't visible wear on lanes that are used mostly by cars like that. Roads have mostly potholes.

What happens on those roads is, sticky asphalt is worn away (but not at the mentioned rate), and what remains are stones which basically don't wear, and tires touch only that. At least highway surface I saw was like that.

What damages roads greatly are trucks, especially overloaded ones (say limit is 15 tonnes, they take 22 tonnes and hope to not be checked... welcome to east european mentality).

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

#223

Post by dsfyu404ed »

spaginal wrote: post #220
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 pick…

The rural poor still drive Cavaiers and whatnot. You absolutely "can" drive a Fiesta (or some other compact) if you live somewhere rural. It just is a standard of living below what most people expect in 2020.

People have the money to buy things that they want and makes their lives easier so it's no surprise that they do.

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

#224

Post by globular-toast »

spaginal wrote: post #220
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 pick…

Rubbish. Go to South Africa and they're driving around in small hatchbacks. Farmers drive pickups (bakkies), but normally sized ones. There's simply no way those monstrous things are a "basic requirement". You are so out of touch with how most people live.

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

#225

Post by bryanmgreen »

spaginal wrote: post #220
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 pick…

I specifically said "standard use".

It's totally understandable that someone as individual contractor might need a bulky pickup to haul construction materials, and I don't take issue with that.

As for SUVs they will obviously be heavier, sure, but how much more value does a Cadillac Escalade provide at over 5,000 pounds compared to an XT4 that weighs, 1,600lbs less? And then how frequently is that value actually utilized?

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

#226

Post by WA »

spaginal wrote: post #220
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 pick…

"Basic requirement for modern living" – what an absurd claim to justify a SUV. I wonder how people in most non-US countries even get by, if the basic necessities of life aren’t met. /s

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

#227

Post by harimau777 »

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…

Isn't one of the biggest reasons to drive a very large car safety? Unless everyone starts driving light weight cars, it seems to me that anyone who does would be putting themselves at risk in the case of an accident.

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

#228

Post by MisterTea »

pinko wrote: post #46
_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…

I remember a civil engineer telling me once that if highways only had cars on them they would last 100 years between repavings.

We have such roads here in NY called parkways, cars only no busses or trucks. Absolute disasters. I frequently take the Belt parkway in NYC to long island via the southern state parkway. That thing looks like it was carpet bombed. They have been patching massive delaminations and joint failures on a weekly basis all winter and we have barely had any freezing weather or snow (it's been spring all winter.) One delam by an interchange was so deep that it took out a few car tires with low side walls.

I was annoyed at these failures and some light reading. You can make more robust roads by making them thicker with a sturdy foundation. Of course this comes at a much higher cost. For example, the autobahn pavement thickness is 27 inches. Whereas by me they mill a few inches off the top of whatever sad situation in below and top it with another 4 inches or so. This is because robust roads are costly and there are so many other things in a muni budget which need attention. So they compromise and lay down a cheap road.

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

#229

Post by cma »

cptskippy wrote: post #184
cma wrote: post #96

Earlier quoted context omitted.

Isn’t Model S closer in size to Camry? A Corolla is closer to model 3 size and more like 2900lbs. The P90D with less range than that 100lbs of gas Camry is 5000lbs.

Interior dimensions are all very similar. Exterior, the Model S is the largest, followed by the Camry, Model 3 then distantly the Corolla. Shldr Hip Head Leg Model S: 57.7 55.0 38.8 42.7 Camry: 57.7 55.4 37.5 42.1 Model 3: 56.3 53.4 40.3 42.7 Corolla: 54.0 53.9 38.0 42.0 WB Len Wdth Hght Model S: 116.5 196.0 77.3 56.5 Camry: 111.2 192.7 72.4 56.9 Model 3: 113.2 184.8 72.8 56.8 Corolla: 106.3 182.5 70.1 56.5

Interior volume of Camry is 115 cu ft (27lbs per interior cubic foot without gas, some marginal amount more with the same amount of gas as P90D's range, which only takes around 60-80lbs of gas or so).

Model S P90D is 120 cu ft (41lbs per interior cubic foot).

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

#230

Post by Marsymars »

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?

The bit about speed prior to lights was meant to be separate from the bit about # of lanes. To clarify - I mean, e.g. that when there's 5km of free-flowing traffic before the lights, and then 1km of congestion, it doesn't matter how fast you drive for those 5km as long as it doesn't delay your passage through the lights. I could halve my speed from the speed limit for those 5km and still arrive at the congestion at the lights before it's my turn to go through them.
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