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The guide to real-world EV battery health

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Re: The guide to real-world EV battery health

#71

Post by epistasis »

hdgvhicv wrote: post #21
cogman10 wrote: post #7

Earlier quoted context omitted.

Bike > walk == public transit > used EV > new EV > used ICE > new ICE That's pretty much the order of "greenness" in personal transport. New EVs will pay off their added carbon footprint in roughly 1 or 2 years in most locations. The ultimate determining factor of how fast that is the energy mix of your local power generation. The only time it'd probably be better to continue using an ICE is if that ICE is a moped or…

My small car does 3,000 miles a year, or 300 litres of petrol a year, or about 1 ton of co2 a year. How many co2 tons are generated in making a new Nissan leaf?

Buy a used Nissan Leaf, then?

The sunk cost fallacy applies not only to dollars, but also to any quantitative phenomenon. The important thing to evaluate is the cost going forward. When you look at the cost of that new Nissan Leaf, you need to amortize the initial carbon cost over the rest of its lifetime, not just the few years you have it!

Re: The guide to real-world EV battery health

#72

Post by jeffbee »

epistasis wrote: post #69
jeffbee wrote: post #12

Earlier quoted context omitted.

It is true though, in some cases. The embodied carbon of a Rivian for example is never paid back by operations. So you do have to exercise good judgement in which EV you choose. The category doesn't always win. In my case I already own a hybrid that I only drive 2000 mi/yr and there is not yet an EV that I could buy with so little embodied carbon that it would make sense to do so. At the rate China is decarbonizing,…

Thanks for linking that Rivian document later, but I think it doesn't support this claim. I'll stick with it's weird 155,000 mile lifetime for the comparison. Rivian: 60,140 kg carbon per lifetime. F150, at 20mpg: 78,740 kg carbon, for fuel alone . So even ignoring the embodied carbon in an ICE vehicle, and paying comparatively high embodied CO2 cost of a new Rivian, it's better to switch immediately, (if CO2 were th…

An F150 is also a poor choice, so I don't think of it as a point of comparison. As an approximation, the mass of any object is related to its embodied carbon, so smaller vehicles embody less of it. Massive vehicles embody current emissions and that is worth considering.

Re: The guide to real-world EV battery health

#73

Post by closewith »

cogman10 wrote: post #57
closewith wrote: post #39

Earlier quoted context omitted.

> However, environmentally an EV will (almost) always beat an ICE, the sooner you get one the better. Especially in a place like the EU where you can get even more environmentally friendly EVs due to the lower amounts of driving. This is simply not true. A new EV will not reach emissions parity with a used ICE car in its average useful lifetime (12.5 years). This isn't close or controversial, so I wonder what the bas…

The payoff period for an EV is anywhere from 15,000 to 25,000mi. The moment any EV crosses that threshold, it becomes better for the environment than the ICE vehicle that you'd otherwise buy. If your used ICE vehicle has 15 to 25,000mi in it, then yeah, replacing it with an EV today is the better choice. It's more a matter of when it will be the better choice. This is only not true if you have very low yearly milages…

> The payoff period for an EV is anywhere from 15,000 to 25,000mi. The moment any EV crosses that threshold, it becomes better for the environment than the ICE vehicle that you'd otherwise buy.

That's the payoff period for the carbon differential between a new EV and a new ICE, not a new EV and your existing ICE, where the carbon cost of production is already sunk. Hence why the GP commented that keeping your ICE is environmentally better than buying a new EV.

Also note that 15-25k miles is 24-40k km, or 2.4-4 years of the average annual mileage in the EU. That's to break even with a new ICE. To break even with a second hand ICE, it's on the order or 15-20 years, or effectively longer than the useful life of the EV.

> If your used ICE vehicle has 15 to 25,000mi in it, then yeah, replacing it with an EV today is the better choice. It's more a matter of when it will be the better choice.

This claim is simply false. There is no point in the lifetime of a used ICE where replacing it with a new EV will result in reduce overall emissions.

Re: The guide to real-world EV battery health

#74

Post by cogman10 »

closewith wrote: post #73
cogman10 wrote: post #57

Earlier quoted context omitted.

The payoff period for an EV is anywhere from 15,000 to 25,000mi. The moment any EV crosses that threshold, it becomes better for the environment than the ICE vehicle that you'd otherwise buy. If your used ICE vehicle has 15 to 25,000mi in it, then yeah, replacing it with an EV today is the better choice. It's more a matter of when it will be the better choice. This is only not true if you have very low yearly milages…

> The payoff period for an EV is anywhere from 15,000 to 25,000mi. The moment any EV crosses that threshold, it becomes better for the environment than the ICE vehicle that you'd otherwise buy. That's the payoff period for the carbon differential between a new EV and a new ICE, not a new EV and your existing ICE, where the carbon cost of production is already sunk. Hence why the GP commented that keeping your ICE is…

> That's to break even with a new ICE.

No, that's to break even with a new EV per the article I posted.

I'd love to see a source that says otherwise. I think you have a bad source for the CO2 emissions of new EV production.

Re: The guide to real-world EV battery health

#75

Post by closewith »

cogman10 wrote: post #74
closewith wrote: post #73

Earlier quoted context omitted.

> The payoff period for an EV is anywhere from 15,000 to 25,000mi. The moment any EV crosses that threshold, it becomes better for the environment than the ICE vehicle that you'd otherwise buy. That's the payoff period for the carbon differential between a new EV and a new ICE, not a new EV and your existing ICE, where the carbon cost of production is already sunk. Hence why the GP commented that keeping your ICE is…

> That's to break even with a new ICE. No, that's to break even with a new EV per the article I posted. I'd love to see a source that says otherwise. I think you have a bad source for the CO2 emissions of new EV production.

From the ICCT, ironically under the subtitle "Addressing misuse of data in the EV debate":

> One common claim is that electric vehicles have higher emissions associated with battery manufacturing. While manufacturing emissions for battery electric cars are roughly 40% higher than for gasoline cars, the ICCT’s research shows that this initial “emissions debt” is typically offset after around 17,000 kilometers of driving, usually within the first one to two years of use in Europe.

The emissions debt is relative to a new ICE.

In cradle-to-grave emissions, electric cars are much lower than ICE cars in lifetime carbon footprint, often 50% lower.

That doesn't change the fact the replacing a used ICE with a new EV will result in increased overall emissions and increase the net carbon footprint.

> I'd love to see a source that says otherwise. I think you have a bad source for the CO2 emissions of new EV production.

This is a completely uncontroversial fact and no environmental or governmental bodies make the claim which you are putting forward, so I'd rather like to see your sources.

Source: https://theicct.org/pr-electric-cars-getting-cleaner-faster/...

Re: The guide to real-world EV battery health

#76

Post by margalabargala »

bryanlarsen wrote: post #67
margalabargala wrote: post #59

Earlier quoted context omitted.

There are two different factors here. One, as you noted, is that electric motors can apply full torque from a stop, increasing perceived acceleration. The other, and more impactful, is that electric motor power scales with cost much more cheaply than gas motors, so vehicles will oversize their electric motors.

There's a third factor. Ev's need to support fast charging. So they need to do support super high voltages and currents. That's much of the expense of a powerful EV. A powerful motor is relatively inexpensive in comparison. If you can charge a car in 20 minutes, the battery and some other circuitry can support discharging in 20 minutes, which is an insane power level.

That's not exactly true. There is some shared wiring between the DC fast charger and the motors, but not so much that the powerful motors are "free". The wires that run between the motors and the battery are long.

I think the larger third factor is regenerative braking. That uses the exact same circuitry as powering the motors, and if you want to be able to brake quickly without the brake pads, that's a lot of kW to be absorbed.

Any way you cut it, I agree, it's an insane power level.

Re: The guide to real-world EV battery health

#77

Post by networkadmin »

singinishi wrote: post #2

Tesla does their own with real world data. It’s a non-issue. Save the planet. Stop making excuses and get an EV.

"Save the planet" by making giant lithium strip mining operations great again. (Safely hidden out of sight in rural China or West Virginia, of course.) City slicker "logic."

No thanks. I will instead actually do something to help the planet by continuing to drive decades year old vehicles whose production costs have long since been amortized, and which have much lower maintenance cost.

Bonus: I can also safely park my old automobiles indoors without any worry of spontaneous combustion. #winning

Another bonus: People all the time chat me up about my old automobiles, wanting to buy them. EV owners don't have the same experience for some reason.

Re: The guide to real-world EV battery health

#78

Post by bryanlarsen »

margalabargala wrote: post #76
bryanlarsen wrote: post #67

Earlier quoted context omitted.

There's a third factor. Ev's need to support fast charging. So they need to do support super high voltages and currents. That's much of the expense of a powerful EV. A powerful motor is relatively inexpensive in comparison. If you can charge a car in 20 minutes, the battery and some other circuitry can support discharging in 20 minutes, which is an insane power level.

That's not exactly true. There is some shared wiring between the DC fast charger and the motors, but not so much that the powerful motors are "free". The wires that run between the motors and the battery are long. I think the larger third factor is regenerative braking. That uses the exact same circuitry as powering the motors, and if you want to be able to brake quickly without the brake pads, that's a lot of kW to…

There's a reason I emphasized the battery in my comment. :)

Re: The guide to real-world EV battery health

#79

Post by epistasis »

jeffbee wrote: post #72
epistasis wrote: post #69

Earlier quoted context omitted.

Thanks for linking that Rivian document later, but I think it doesn't support this claim. I'll stick with it's weird 155,000 mile lifetime for the comparison. Rivian: 60,140 kg carbon per lifetime. F150, at 20mpg: 78,740 kg carbon, for fuel alone . So even ignoring the embodied carbon in an ICE vehicle, and paying comparatively high embodied CO2 cost of a new Rivian, it's better to switch immediately, (if CO2 were th…

An F150 is also a poor choice, so I don't think of it as a point of comparison. As an approximation, the mass of any object is related to its embodied carbon, so smaller vehicles embody less of it. Massive vehicles embody current emissions and that is worth considering.

The Rivian is a truck, the F150 is by far the best selling truck, I don't think there could be a better comparison.

What would you compare the Rivian to?

Re: The guide to real-world EV battery health

#80

Post by jeffbee »

epistasis wrote: post #79
jeffbee wrote: post #72

Earlier quoted context omitted.

An F150 is also a poor choice, so I don't think of it as a point of comparison. As an approximation, the mass of any object is related to its embodied carbon, so smaller vehicles embody less of it. Massive vehicles embody current emissions and that is worth considering.

The Rivian is a truck, the F150 is by far the best selling truck, I don't think there could be a better comparison. What would you compare the Rivian to?

That only works if you take it at face value that buying either of them is a rational transportation choice, which I reject. Even if I accept the people need a weird truck-shaped thing with a useless 4.5-foot bed, a far better choice on emissions grounds would be the Ford Maverick XL, which has a battery 1% as massive as the R1T's battery, yet this tiny battery cuts the per-mile GHG emissions in half. The embodied carbon payback distance of an R1T versus a Maverick XL is over 100,000 miles.

My kid races mountain bikes so I have become extremely familiar with Rivian (and Cybertruck) MTB Dad, and I think they are a joke. With only a little planning I can get three bikes and three riders in a Honda Insight, while R1T Dad needs an optional accessory to get even one bike in the bed. People choosing these things are, 99% of the time, not behaving rationally. They are buying luxury goods that they believe signal their environmental credentials.

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