EVs have very low brake wear because you simply aren’t using the friction brakes at all most of the time.
A lot of EVs even have smart “blended” brake pedals that preferentially apply regen braking when you press the pedal. Only in particularly hard stops will the friction brakes get used.
An easy way to test/observe this is simply to check for wear on the brake pads of EVs compared to combustion vehicles of similar mileage.
Tires, on the other hand, do tend to wear out quicker in an EV. Partly due to weight and also due to higher performance/acceleration compared to combustion models.
This little friction break usage is actually something which manufacture need to consider. They need to activate once in a while to stop rust and other problems.
They almost certainly do. For example, our Chevy Volt (EV + gasoline engine range booster) puts the engine through a maintenance phase if you haven’t used the engine in a few weeks, and will force the engine to consume any fuel left in the tank if it hasn’t been refilled in several months.
But I know at least one EV maker that has a manually selected mode that guides you through driving with the brakes engaged for surface treatment, as rust buildup will be the main issue.
In the US, the average car weight and the average EV weight are basically identical. (4300 pounds vs 4400 pounds). When you compare similarly sized models the EV tends to be about 10% heavier, but gasoline cars tend to be larger than EV's.
In the EU an average car is 1400 kg (3000 lbs), with most vehicles probably in the 1000-1200 kg range. We don't really want the average here, but the median - and we don't want to compare to the average EV, but to the equivalent EV - comparing an F150 to, say, a model 3 isn't right.
A BYD Dolphin, roughly sized like a VW Polo, is some 400kg heavier than the polo. A Polestar 2 is roughly 500 kg heavier than equivalent sized cars. In other words, something like 33% heavier.
FWIW I learned semi recently that cars get heavier and heavier because it improves their “ecology” rating… the ratings consider that moving 50% more weight with only 33% more gas is better than moving 0% extra weight with 0% more gas. And so a heavier car that uses a little more gas gets a better energy rating.
It’s moronic. But that’s how it works and why cars are getting bigger and bigger.
The VW Golf Mk8 might be a better comparison with an unloaded curb weight of 1255 kg, which reduces the gap from 543kg to 403kg.
(Note that for the gasoline and diesel cars, lighter trims give longer range, whereas it is opposite for electric cars, and that a fully loaded 45L tank of a polo weighs less than 40kg, especially if gasoline)
The lower battery trim is not available in all markets, and only does 300km on a charge which is below average. As such the minimum weight will have to be the 1658 kg value.
The BYD is taller to offset the battery, making the size misleading. However, the golf is not particularly a particularly good or space efficient car - others will do better at similar or lower weight.
250kg seems like a fair minimum weight increase, roughly 20%. The larger the car, the larger the gap though, as the rocket equation catches up - see a Skoda Octavia vs. a Polestar 2.
EVs are still way more efficient, but that doesn't mean we should turn our blind eye to making an already bad tire problem worse.
Same tier EVs are always more powerful than gasoline cars as they are generally just battery limited, not motor limited.
EVs are just a better tech in that regard, and buyers are not buying a Dolphin or golf based on torque or max HP. They're compacts in the same space. Someone looking at a dolphin would more likely be looking at the lighter eco motors.
This is true in other tiers too, e.g. a performance tier gasoline car might be 250-350 HP, while the same tier EV might start at 450-550hp just because they can.
The difference within a tier, simply based on the fact you're replacing at best a lightweight 100kg engine with 400-500kg worth of battery, can't be as small as you suggest.
With larger EVs, the battery weight is much greater, increasing the impact. Rocket equation and all.
They're not inherently heavier. They're only heavier if you put a long-range battery in them, even then it's not by very much, and even that may not persist as higher energy density batteries are developed.
Or to put it another way, the difference between a small car and a large SUV is far greater than the difference between an electric car and a gasoline car.
A Tesla Model Y is 30% heavier than a Honda CRV. They have alot of other advantages, and are about the same weight as a three-row SUV and lighter than a Tahoe on a truck frame.
We shouldn’t be singling out EVs if we suddenly care about tire wear… it’s pretty ridiculous.
The lightest current Tesla Model Y is ~25% heavier than the lightest current Honda CR-V. The heaviest current Model Y is ~12% heavier than the heaviest current CR-V (hybrid). A Jeep Grand Wagoneer is ~280% heavier than a Nissan Versa.
Again, bike-shedding stats on EVs is a waste of time if you care about pollution from tire wear.
If we want to reduce particulate pollution, we’d have regulations to govern acceleration on EVs, make tire monitoring more annoying, and have manufacturers certify tires and make compliance required during state emissions inspections, and get aggressive about the motor carrier overweight enforcement.
If Tesla or other EVs have a problem here, it’s that they are putting inappropriate tires on the cars.
There’s a great deal possible that could reduce pollution that has nothing to do with tires. Outlawing non hybrid gas / diesel cars for example would be a significant step forward. As would favoring rail over big rig trucking etc.
Instead the topic is almost exclusively brought up as an attack without any real world studies supporting the ideas presented. Because actual studies show EV’s improve air quality over ICE engines.
I think we violently agree with respect to EVs… it’s just whataboutism.
But I do think tires are a significant environmental problem, especially in urban areas and when combined with diesel soot. We’re also poisoning soil by allowing shredded tires to be used as mulch, which is gross in many levels. Shredded tires are also used as aggregate for roads, so road wear also contributes to particulate pollution from tires.
Those are wildly different crossovers. That glass roof on the Y adds a lot of weight, it’s kind of silly how popular such an impractical feature became.
The other common issue with EV’s is many don’t integrate the batteries casing as a structural element. Skipping the lead acid battery would also be useful, but that’s a different issue.
But the fact that EV brakes don't wear at nearly the same rate as ICE brakes still stands.
My EV6 (pretty heavy car) manual explicitly says "you should probably do some hard breaking from moderate speed to prevent corrosion on the brake discs".
Because 90+% of the time when you press the brake pedal the friction brakes aren't being used at all, it's all regen.
It's true they are not that much heavier in terms of pure numbers. But road wear is a proportional to the difference in axle weight to the fourth power.
> we found that the car emitted 5.8 grams per kilometer of particles. 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.
They took plastic shedded by a gas car on non-EV tires, and compared it by weight to safety limits for gaseous emissions. This makes as much sense as saying that a lump of coal has 1,000 times more carbon than the safety limits for carbon monoxide.
That doesn't pass a sniff test; emitting 5 grams of tyre rubber per kilometer, a 12Kg tyre would be completely vanished in 3000km but really they can last 60,000km with only the tread worn down beyond safe levels and the bulk of the tyre still there.
It doesn't matter though? Less braking material used equals less particles emitted. So if we accept that brakes on EVs last longer (and are otherwise similar in size), then they pollute less.
My Volvo XC60 T8 is not even a full EV but after 5 years of ownership the brakes on this 2200kg, 400bhp SUV are only 10% worn - it's all thanks to regenerative braking with the EV motor. It definitely makes a massive impact on how quickly the brakes wear out(as in - much much much less than in a normal car).
If you want to go into the details of this, for all the things people hve mentioned, you have to calculate the road wear done by trucks carrying fuels to stations every day. Electricity does not need the same regular road wear as ICE vehicles do.
Sure. Because windmills and photovoltaics grow naturally from seeds. You need quite a bit of an equipment to put up one windmill. They are usually built in some distance from an existing road. So you need special service roads. Those need to be wide and take heavy load because the equipment like cranes need space and are themselves heavy. Then you need special transport because main components like propellers are oversize load. Then you need to transport them hundreds for kilometres…, and then you need the rest of the infrastructure to distribute generated electricity. Yes, let’s compare apples to apples.
Yes and what's the service life for that windmill or solar panel? What's the service life of the distribution system?
And what was the cost to build out and constantly repair the refinery?
The problem you have with your talking points is that solar and wind both have decades of service in them whereas fossil fuels are single use product. Further, once the infrastructure is created large portions of it can be reused when solar and wind hit their end of life. You only need new lines and roads for new installations.
All energy collection will have some environmental impact. It just so happens that fossil fuels have an outsized impact for the energy they create.
I'm not an absolutist about crude oil. It'll likely have a place in society for a long time.
With that said, it's a matter of degree and where it should be deployed.
If, for example, burning 1 gallon of gas sets up a power generation which produces the equivalent of 20 gallons of gas without emissions, that's a worthy trade off.
As it turns out, that's roughly the energy trade-off for new solar/wind installations assuming a pure fossil fuel grid.
What you are saying isn't a gotcha. The entire cycle of CO2 released for fossil fuel use is not comparable to the CO2 released installing renewables. That some is released is meaningless.
It is in fact straightforward to assume EVs create way, way less brake dust, because of how much less often they need brake replacements than ICE vehicles with the exact same brakes.
