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EV batteries alone could satisfy short-term grid storage demand as early as 2030

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Re: EV batteries alone could satisfy short-term grid storage demand as early as 2030

#52

Earlier quoted context omitted.

Assuming Tesla prices and full cycling of battery (aka from 100->0), draining a kWh puts about 2cents wear on your battery, so compensation would need to be above that price. In practice you'd never allow your operator to drain you to 0, so 2 cents is very much on the high side. In the California Tesla VPP trial, they pay 50 cents per kWh. (correction: 20cents wear, not 2cents)

I calculate about $12 per Model Y full battery cycle, how did you get 2 cents? $12,000 (Model Y bat replace cost) * 300(miles for full drain)/300,000(total miles per pack) = $12 per cycle Edit: or 18 cents per kWh

It's not per cycle, but per kWh.

In any case I'm getting 10-20 cents depending on battery pack size and chemistry.

Re: EV batteries alone could satisfy short-term grid storage demand as early as 2030

#53

Earlier quoted context omitted.

Assuming Tesla prices and full cycling of battery (aka from 100->0), draining a kWh puts about 2cents wear on your battery, so compensation would need to be above that price. In practice you'd never allow your operator to drain you to 0, so 2 cents is very much on the high side. In the California Tesla VPP trial, they pay 50 cents per kWh. (correction: 20cents wear, not 2cents)

I calculate about $12 per Model Y full battery cycle, how did you get 2 cents? $12,000 (Model Y bat replace cost) * 300(miles for full drain)/300,000(total miles per pack) = $12 per cycle Edit: or 18 cents per kWh

The 2 cent figure is per kWh, not per cycle. Multiplying by the 75kWh pack size gives $1.50.

What about the remaining 10X? The calculation you’re doing isn’t the right one, because the battery wear isn’t directly related to miles driven; Tesla’s battery warranty is pricing in a “full stack” picture of battery degradation while actually driving.

Your computation implies that the battery has 0 value after ~1000 cycles, but battery manufacturers commonly warranty 3,000-5,000. In addition, cycle count is only one variable affecting degradation, others include the depth of discharge, the charging and discharging profiles, the thermal management, etc.

(This is one reason why a 10-year-old Tesla has noticeably different battery degradation than, say, a 10-year old Nissan Leaf, which has no thermal management and a very poor BMS)

Finally, even when battery degradation occurs, it doesn’t remove the battery’s entire capacity, so degraded batteries can still be used for stationary storage applications. While an extreme degradation like 50% is very bad for an automotive application, it doesn’t matter so much for small-scale grid storage, since space is usually not the limiting factor.

Re: EV batteries alone could satisfy short-term grid storage demand as early as 2030

#54

I would not sell cycles from my EVs NMC battery.

Hmm, but how often and for how much? If you could get $500 to discharge 50% would that make it worth your while? If you only did it once a month? There are price situations like that on the grid already.

Re: EV batteries alone could satisfy short-term grid storage demand as early as 2030

#55

We're nowhere near close to home charging for the number of EVs estimated by 2030. Go ask around, very few organizations are working on it compared to public chargers. Apartment managers and condo associations aren't demanding them and only homeowners have a say, after they pay for the upgrade. Not to mention, the power companies hate the idea. They won't even let people with solar panels feed their excess power to t…

> They won't even let people with solar panels feed their excess power to the grid. Is that true? If so, TIL...

Depends on your state https://www.solarpowerworldonline.com/2020/03/which-states-o...

Re: EV batteries alone could satisfy short-term grid storage demand as early as 2030

#56
EVs with BrakeFlow resistive protection against thermal runaway also will have a big impact –– allowing for faster discharge into the grid. Increasing cRate for grid services can "bring forward" the point in time –– so 2030 could even happen a few years sooner if these high performance batteries from Enovix come to the EV market soon.

Re: EV batteries alone could satisfy short-term grid storage demand as early as 2030

#57

We're nowhere near close to home charging for the number of EVs estimated by 2030. Go ask around, very few organizations are working on it compared to public chargers. Apartment managers and condo associations aren't demanding them and only homeowners have a say, after they pay for the upgrade. Not to mention, the power companies hate the idea. They won't even let people with solar panels feed their excess power to t…

> They won't even let people with solar panels feed their excess power to the grid. Is that true? If so, TIL...

It is not true, but they do make it very hard in some places and as a group utilities do kind of hate the idea. Almost all states require net metering, which what allows people to sell their solar to the grid, and there is some federal regulation too (https://en.wikipedia.org/wiki/Energy_Policy_Act_of_2005). Despite these requirements most utilities make it pretty hard to set up.

Re: EV batteries alone could satisfy short-term grid storage demand as early as 2030

#58
post #23
post #2

I think EV owners would need to find some level of compensation for the additional cycles they would incur. Electric vehicles are expensive because of the battery so deteriorating the life of one of the most costly parts of the car doesn't feel like a great solution.

This makes much more sense with large lifepo4 chemistry batteries that are expected to outlive the car by a wide margin. Lifepo4 batteries > 50kwh should easily handle 500,000 miles. Higher performance lithium ion will degrade at a rate faster than any expected return from a scheme like this. At least in Northern California it’s now cheaper for me to run solar+battery off grid than to pay pge. Lifepo4 pushes it over…

> If off-grid is competitive, selling at peak prices is a no brainer.

So why isn't the utility managing the storage directly then? Aren't they best suited to do this???

Or is this article just saying that EV car batteries could?

Re: EV batteries alone could satisfy short-term grid storage demand as early as 2030

#59
The Taiwanese scooter company Gogoro recently announced something similar: Their scooters come with swappable batteries that you rent. The swapping station they have throughout the city are basically walls full of batteries. Since the company owns all the batteries, they can then use them to provide power to the grid during peak load.

Re: EV batteries alone could satisfy short-term grid storage demand as early as 2030

#60
post #2

I think EV owners would need to find some level of compensation for the additional cycles they would incur. Electric vehicles are expensive because of the battery so deteriorating the life of one of the most costly parts of the car doesn't feel like a great solution.

The distributor should just pay the generation fee to the car owners just like they would a power plant.
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