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EVs Are Essential Grid-Scale Storage

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Re: EVs Are Essential Grid-Scale Storage

#41

Post by Maxion »

londons_explore wrote: post #25
Yizahi wrote: post #10

Aren't people wary about using their very expensive car batteries for the grid? E.g. imagine you plug in your phone for the night, but instead of a single top up change it is now constantly discharging and charging again. Lifetime of pocket sized batteries is not too great even now, and in such scenario they will go bust 2-3 times faster, in year instead of 3 or so. Also discharge swings would be probably much bigger…

Luckily, any degradation can all be predicted ahead of time. A 60kwh car battery might cost $10k, and allow 2000 charge cycles. So each kwh cycled into and out of the battery costs 8 cents. So a smart algorithm can decide it's worth draining the battery back into the grid if the profit to be made is more than 8 cents. Buuuut ... Delaying charging till later is free. So another car owner's car might see on the futures…

This can be done by using a smart AC charger.

In europe (At least) the company Easee makes AC chargeres that are WiFi / 4G enabled. In Sweden (And Norway) you can connect them to a service like Tibber, which allows you to automatically enable/disable charging with the electricity price, assuming you have a spot price electricity contract.

https://tibber.com/en/product/easee

Easee chargers also have a pretty bitching API, so you can also make your own automations using e.g. home assistant or what have you.

Re: EVs Are Essential Grid-Scale Storage

#43

Post by jonplackett »

causi wrote: post #23

Even if you completely do away with concerns of battery wear, I'd only be willing to participate in this as long as my household still had an ICE vehicle to fall back on. When I get home and plug the car in I don't want to have to think about whether I might want or need to leave the house at a particular time with a particular charge; I just want the charge to be as high as possible as soon as possible.

All you need is a ‘no selling electricity today please’ button.

Re: EVs Are Essential Grid-Scale Storage

#44

Post by danuker »

londons_explore wrote: post #25
Yizahi wrote: post #10

Aren't people wary about using their very expensive car batteries for the grid? E.g. imagine you plug in your phone for the night, but instead of a single top up change it is now constantly discharging and charging again. Lifetime of pocket sized batteries is not too great even now, and in such scenario they will go bust 2-3 times faster, in year instead of 3 or so. Also discharge swings would be probably much bigger…

Luckily, any degradation can all be predicted ahead of time. A 60kwh car battery might cost $10k, and allow 2000 charge cycles. So each kwh cycled into and out of the battery costs 8 cents. So a smart algorithm can decide it's worth draining the battery back into the grid if the profit to be made is more than 8 cents. Buuuut ... Delaying charging till later is free. So another car owner's car might see on the futures…

It worries me that if industrial-purpose batteries cost the same and have similar degradation, grid services will also decide not to charge/discharge if the profit is less than 8 cents.

This tells me that Li-Ion batteries are far from the ideal medium for grid storage.

Re: EVs Are Essential Grid-Scale Storage

#45

Post by Maxion »

locallost wrote: post #33
Maxion wrote: post #13

Unless the $/kwh or lifecycle count of EV batteries change significantly, using them as a grid-scale storage is just not financially feasible. E.g. a NMC battery has a lifespan of around ~2000 cycles, a model S 90 D has a 90 kWh battery. That's around 180 MWh of total energy that can be moved through the battery before it is dead. On Reddit, a tesla user reports ( https://www.reddit.com/r/teslamotors/comments/v4dqkp/…

During most of last year prices in Europe were routinely over 300, 400 even occasionally over 1000 per MWh because there was an energy shortage. At the same time the prices can easily go negative if the conditions are favorable for renewables. It's not crazy to think that you would be paid to charge your car when there is an excess and then get paid a lot when there is a shortage. I don't know who would say no to thi…

My point is mainly that there are plenty of options available to stabilize grid prices that are way cheaper than using EV's. Europes energy crisis is temporary, over time the price fluctuations will go down.

Re: EVs Are Essential Grid-Scale Storage

#46

Post by trashtester »

londons_explore wrote: post #25
Yizahi wrote: post #10

Aren't people wary about using their very expensive car batteries for the grid? E.g. imagine you plug in your phone for the night, but instead of a single top up change it is now constantly discharging and charging again. Lifetime of pocket sized batteries is not too great even now, and in such scenario they will go bust 2-3 times faster, in year instead of 3 or so. Also discharge swings would be probably much bigger…

Luckily, any degradation can all be predicted ahead of time. A 60kwh car battery might cost $10k, and allow 2000 charge cycles. So each kwh cycled into and out of the battery costs 8 cents. So a smart algorithm can decide it's worth draining the battery back into the grid if the profit to be made is more than 8 cents. Buuuut ... Delaying charging till later is free. So another car owner's car might see on the futures…

> Buuuut... Delaying charging till later is free.

This functionality is already there.

> So each kwh cycled into and out of the battery costs 8 cents.

This is quite much. If you add other infra overhead, feeding power back into the grid is not going to produce much revenue for the individual unless the selling price is maybe 20 cents above the price when charging.

On the other hand, something that MAY make more sense, is if the car battery can be used to provide power to the owner's own house during short price peaks. This might allow some savings even in stable grids, but the killer app would be in grids that have rolling blackouts during high demand periods.

And even for grids where blackouts are infrequent, if your car can serve as large UPS for your house (combined with a large capacitor to keep the power stable), such functionality in the charger may be worth the cost of the hardware for many people. (Bringing the number of units up and hence the cost per unit down over time.)

Still, though, for grid stability it is probably much better to use dedicated batteries as part of the grid itself than to use car batteries.

Re: EVs Are Essential Grid-Scale Storage

#47

Post by pclmulqdq »

londons_explore wrote: post #30
Maxion wrote: post #13

Unless the $/kwh or lifecycle count of EV batteries change significantly, using them as a grid-scale storage is just not financially feasible. E.g. a NMC battery has a lifespan of around ~2000 cycles, a model S 90 D has a 90 kWh battery. That's around 180 MWh of total energy that can be moved through the battery before it is dead. On Reddit, a tesla user reports ( https://www.reddit.com/r/teslamotors/comments/v4dqkp/…

> 106 USD per MWh hour, which is more than most generation sources Minute by minute electricity prices vary really widely. It isn't unusual for prices to spike up 10x briefly at peak times. Most power stations have too high a capital cost to only run 2% of the time... whereas your tesla battery has no capital cost, so using it to power the grid 2% of the time when the prices are sky-high is very attractive.

So people being asked to discharge their Tesla into the grid should be paid a significant premium, right?

Since they are providing power on demand in a way that doesn't have upfront costs, that should mean that car-based power demands a cloud-like premium (10-50x over traditional servers) over traditional power plants.

They are getting a little premium today, but likely won't once this practice becomes normal.

Re: EVs Are Essential Grid-Scale Storage

#49

Post by Yizahi »

londons_explore wrote: post #25
Yizahi wrote: post #10

Aren't people wary about using their very expensive car batteries for the grid? E.g. imagine you plug in your phone for the night, but instead of a single top up change it is now constantly discharging and charging again. Lifetime of pocket sized batteries is not too great even now, and in such scenario they will go bust 2-3 times faster, in year instead of 3 or so. Also discharge swings would be probably much bigger…

Luckily, any degradation can all be predicted ahead of time. A 60kwh car battery might cost $10k, and allow 2000 charge cycles. So each kwh cycled into and out of the battery costs 8 cents. So a smart algorithm can decide it's worth draining the battery back into the grid if the profit to be made is more than 8 cents. Buuuut ... Delaying charging till later is free. So another car owner's car might see on the futures…

Now that's an interesting idea. Let's see how it will unfold globally. Maybe it will indeed be painless feature.

Re: EVs Are Essential Grid-Scale Storage

#50

Post by dismalpedigree »

throwawaaarrgh wrote: post #14
Cthulhu_ wrote: post #9

Cool, but will the energy company pay for the wear and tear? Do you get paid extra if you promise to not use your car between hours X and Y?

an energy company paying customers extra? lolllllll. if anything they're gonna find a way to charge you for the privilege of giving them power

This is completely accurate. Often done by shifting the reported cost structure to claim transmission is vastly more expensive than generation. You are not doing transmission, they are so you pay them more.
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