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by jchonphoenix 1389 days ago
How does this work?

Brake pads don't seem like they should be different on an EV. It's really just the engine components that should have less wear and tear and those only come into play at the 30k and 60k mark

8 comments

Brakes get a lot less wear because you’re mainly relying on regenerative braking using the electric motors in reverse. If your driving style is gentle enough, it can bring the car to a complete stop in a reasonable distance. The mechanical brakes are then only engaged when the car is fully stopped already.
EV with KERS use brake pads much much less, my mechanic can confirm, he always complains how much less work he has to do on an electric car.
I drove down a hill 15 minutes and didn't use the breaks once.

The display then said 'recovered 9x%'.

It also feels less wasteful on the Autobahn as well because quick deceleration is also possible.

The adaptive Speedcontrol can handle like 99% of the cases were cars slow down or switch into your lane.

With the general speed limit in USA I think that should also be possible.makes driving much nicer

Adaptive cruise control in the us means jumping on the brakes every 30 seconds when someone goes straight from the on-ramp to the leftmost lane at 20 under the limit.

I only get to use my cruise control at night

Electric vehicles don't use the brakes that much as they can slow the car down by switching the elctric motors from using electricity to accelerate to using the wheels to generate electricity thereby slowing the car down.

Case in point that whole situation "recently" where a woman got a Tesla with no brake pads installed on it.

Oil, filters and work on them is pricy at the official dealers (if you care about warranty). Also more failure points - turbines, injectors, gas pump, exhaust, gearbox, oiling system in general. Just a single gearbox or turbine failure can cost thousands. EVs are really cheaper in general, however you compare.
Where does getting an oil filter changed by a non dealer void the warranty?

Oil/air filters and brakes are $50 and $500 at most. Everything else is pretty reliable for a couple hundred thousand miles assuming a decent brand car like Toyota or Honda.

At US gas prices, I have yet to see an EV be shown to be a better value than a car/minivan/SUV/pickup truck, especially if driving 10k miles or less per year. The upfront cost on EVs is huge, and many alternatives such as minivans do not even exist yet.

I need to do yearly maintenance at the dealer (or if I exceed some fixed mileage before that), they do the oil change in the course of that. If I would skip yearly maintenance the warranty is voided.

PS: that's for Mazda car.

That’s definitely not the case in the US (see Magnuson-Moss 1975) and many other countries have similar laws.
https://www.fhwa.dot.gov/ohim/onh00/bar8.htm

10K miles or less is a bit of an outlier.

I would not be able to discern 10k miles or less for a car is an outlier from those data points, it does not say anything about the underlying distribution.

Not to mention the whole female column is pretty much 10k and below, as well as men over 65.

This is a little bit better breakdown, but I could find miles driven by decile. I would assume it greatly differs by location and is greatly skewer by people who drive a lot.

https://www.thezebra.com/resources/driving/average-miles-dri...

Either way, the purpose of the miles driven per year in cost calculations is because after a certain amount of miles, the up front higher cost of electric is offset by lower per mile costs of driving electric. Assuming fuel costs stay the same, then people who drive less have less incentive to go electric.

The up front higher cost is disappearing as they ramp up production and is predicted to cross over within a few years. The fuel costs and carbon intensity of the running costs are also predicted to diverge in EVs favor.

Presumably part of this is greater efficiency, which would impact the C02 emissions too.

So any small savings are that possibly exist today in theory are likely wiped out by depreciation on the vehicle when you go to sell it to someone else, who likely drives an average amount of miles and so wants to buy a cheap to run vehicle

TCO calculations can deal with most of this, the one I linked to does highway and city mileage seperately and lets you choose a state for electricity and gas prices. There's no need for vague blanket rules.

Why don't you demonstrate a realistic scenario to substantiate your claim that:

> At US gas prices, I have yet to see an EV be shown to be a better value than a car/minivan/SUV/pickup truck, especially if driving 10k miles or less per year.

But, none of that really matters because the average car is much better off as an EV, and this is just fiddling around the edges to distract from that basic truth.

> The up front higher cost is disappearing as they ramp up production and is predicted to cross over within a few years.

Maybe. I am not disputing it will not. I do not know about “a few years”. I would still place my TCO bets on gas until I have some proof of longevity from electric vehicles, assuming I do not drive 20k miles per year.

> So any small savings are that possibly exist today in theory are likely wiped out by depreciation on the vehicle when you go to sell it to someone else

This is only a factor if you plan on selling it before the end of your life, or the end of the vehicle’s life.

> Why don't you demonstrate a realistic scenario to substantiate your claim that:

The fact that if I were to buy a car today in the US, there is no option for an electric Sienna or Odyssey minivan or equivalent. No electric car gives that kind of passenger space or cargo room and versatility for a family.

It's not that any work voids the warranty, but for example I got extra 2 years warranty by servicing at the official dealer rather than somewhere else.
> How does this work?

Maintenance in the first 100-150k (I really want to say ~200 but that will depend largely on the treatment the vehicle gets in the first 100) is basically nothing other than short term wear items (pads and tires) and preventative maintenance (transmission fluid at 50k, air filter at 20k, stuff like that).

As EVs get long in the tooth they will exhibit all the same "stuff between the vehicle and the road is wearing out" problems that literally every other wheeled vehicle on this earth exhibits. It's not like equipping a car with an electric drive train makes all the steering and suspension parts (that account for the bulk of the late in life maintenance) magically cease to exist

Except there are less parts overall in an EV. Way way way way less parts. And way way way way less fluids for said parts.

Less parts means less things to maintenance. Less fluids means less things to refill.

In terms of "wearing out" the big questions really centers on the battery itself. We're seeing pretty low battery degradation on Teslas that have been on the road for 5+ years [1]. The data indicates that at 100k miles they lose about 5% power, which is pretty good. This is data about Teslas specifically though (they're the only car company that has enough long term data at scale to do this analysis on) and every car company has a different battery composition.

But aside from the battery (which is a BIG aside), there is a lot less parts (especially moving parts) that have to be watched/maintained/etc.

[1] https://electrek.co/2020/06/06/tesla-battery-degradation-rep...

I imagine the wear on the pads is reduced by the regenerative braking from the motors.
Eliminated almost entirely, they should revert to drums on EVs as discs get rust on them.
This has started, ID.3 and 4 has them on rear wheels I think.

https://www.thedrive.com/news/36683/why-the-new-volkswagen-i...

They're also looking at making light weight aluminum brake pads that don't rust from less use.

"The brand also says that drum brakes offer superior performance and reactivity after long periods of disuse"

Sounds like marketing to excuse putting drums on the rear of a $50K vehicle. As soon as I back out of the driveway in our Leaf, because there's no regenerative braking in reverse at 5mph, it knocks the light layer of rust off the discs and we're good to go. I mean, we've been driving this car for eleven years, and not once from a cold start have we gone to hit the brakes outside the regen envelope (say, when we've charged to %100, and nowhere to put that regen energy) and said, "OMG! OMG! Poor brake performance!"

What VW really said in that link was, "doesn't need rear discs: regen braking".

Why are discs more susceptible to rust than drums?
The braking surface is on the outside, more exposed to water splash. Drums are not "sealed", but are much more closed off.
In an EV you don't actually use the brakes if you don't brake hard, engine does energy recovery instead.