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Comment by oblio | Hacker News Reader

Somewhat off-topic, but maybe someone knows.

There's one thing that worries me about EVs: local pollution.

So, ICE cars release CO2 + they release local pollutants (NO, CO, etc), particulate matter, that kind of thing.

EVs obviously don't directly release CO2 nor do they release those local pollutants.

However, EVs are on average much heavier (probably 200-400kgs heavier), which means that they probably need bigger tires and they wear them out faster. They probably also wear roads faster.

For local pollution, is the extra tire & road wear and tear equal or worse to the ICE tire & road wear and tear + exhaust gases?

Does anyone know any studies about this?

View on HN

https://www.oecd-ilibrary.org/sites/e1bc711b-en/index.html?i...

"This chapter estimates the non-exhaust PM emission factors from electric vehicles and compares these factors with those of internal combustion engine vehicles. Assuming lightweight EVs (i.e. with battery packs enabling a driving range of about 100 miles), the report finds that EVs emit an estimated 11-13% less non-exhaust PM2.5 and 18-19% less PM10 than ICEVs. Assuming that EV models are heavier (with battery packs enabling a driving range of 300 miles or higher), however, the report finds that they reduce PM10 by only 4-7% and increase PM2.5 by 3-8% relative to conventional vehicles. Additional simulations indicate that the uptake of electric vehicles will lead to very marginal decreases in total PM emissions from road traffic in future years. In scenarios where electric vehicles comprise 4% and 8% of the vehicle stock in 2030, their penetration reduces PM emissions by 0.3%-0.8% relative to current levels."

The question is reasonable and I'm not sure why it was heavily downvoted, tire wear and road wear depends polynomially on the vehicle weight (I remembered it's the cube, I tried Googling but Google has turned completely fucking useless for anything serious)

edit: it's the 4th power for road damage (!): https://www.denenapoints.com/relationship-vehicle-weight-roa...

It's downvoted by EV fanboys because EVs must be pushed into the mainstream at all costs. I'm not kidding.

To EV fanboys: issues should be discussed, not hidden away because they're not nice or not solved yet.

I think EVs are a great idea, they're great for the environment and personally, I was hoping they'd also be great for air quality. But it seems the air quality part will not happen for quite a long time, until batteries become much lighter, unfortunately.

Tire wear you can just directly calculate from the useful lives of tires on a given car. Search around on Tesla owners' forums to see at what mileage people are replacing their tires. Then you just back it out from diameter x width x tread depth. Teslas come out poorly on this because they are a performance-focussed car with large, soft tires. Some other electrics like the BMW i3 have tiny rock-hard tires that practically never wear out.

> Teslas come out poorly on this because they are a performance-focussed car with large, soft tires.

Even the Model 3? That's more of an economy car, I'd expect it to have practical tires.

It depends on the wheel package.

Interesting. So, in practice, people who care about the environment should probably get the base packages, which most likely have firmer tires?

I don't have a specific study but regenerative breaking as used in commercial EVs would mean less particulate from breakpads etc. not more.

My DSG gearbox does regenerative braking all on its own and the brake life is really long.

Though I did discover when I do replace them they won’t be quite as good because copper sintering has been outlawed due to metal pollution.

MUCH less. Like one or two sets of break pads on a car for its lifetime.

I'd be surprised if it was even 1. There was no measurable wear on the brake pads over the lease of my Nissan Leaf. It didn't even engage the hydraulic brakes often enough to knock the rust off the discs.

Good point about break pads, I completely forgot about those.

The thing is, that's another aspect where I'd naively assume tires are a much larger factor. I'm probably wrong, though.

It turns out that EVs are not much heavier when compared to the similar priced luxury market. Model 3's are 3,648 to 4,250 lbs where as BMW M3's are 3,840 to 3,990 lbs. Model S is 4,561 to 4,766 lbs and BMW m7 is 4,244 to 4,855 lbs.

They don't scale down, though.

VW id.3 weight:

1,812 to 1,935 kg

VW Golf weight:

1,302 to 1,630 kg

That's 18% to 38% heavier, it's a huge difference.

And most cars are not luxury cars, across the world. Nor are they SUVs.

I fear we're both going to wreck roads much faster and affect air quality, at least for the next 5-10 years, until we improve battery capacity and reduce their weight :-(

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