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EVs Are Essential Grid-Scale Storage

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Re: EVs Are Essential Grid-Scale Storage

#71

Post by coffeebeqn »

dbingham wrote: post #58

Counter point, getting the resources for those batteries and building them has no small environmental impact - including carbon impact: https://www.theguardian.com/us-news/2023/jan/24/us-electric-... > The US’s transition to electric vehicles could require three times as much lithium as is currently produced for the entire global market, causing needless water shortages, Indigenous land grabs, and ecosystem destructi…

It’s not just cars. How would homes store energy overnight without lithium? The current best available home storage is still lithium based (lithium iron phosphate).

Re: EVs Are Essential Grid-Scale Storage

#72

Post by dahfizz »

coffeebeqn wrote: post #63
college_physics wrote: post #60

This feels gimmicky and fragile. If distributed / decentralized storage is required (sounds like a good idea overall) it is surely better to have stationary installations, with larger batteries and connectivity optimized for that purpose, not using the EV batteries currently developed for moving these two-ton exosceletons to random places... In fact you want to have the option to significantly reduce EV usage as othe…

It is gimmicky but the batteries in EVs are really big and especially in the US everyone has a car. I don’t see a large amount of houses getting a 30-70kWh battery unless they install rooftop solar. So what are the realistic options ? Other than large infrastructure spend to get grid batteries which is probably what will happen in the end

> So what are the realistic options?

Maybe the utility companies could do their job and provide a reliable electricity source, instead of outsourcing it to customers.

Re: EVs Are Essential Grid-Scale Storage

#73

Post by vbezhenar »

raxxorraxor wrote: post #35
discordance wrote: post #4

Earlier quoted context omitted.

$300/kWh for home storage is readily available. E.g. https://signaturesolar.com/eg4-ll-lithium-battery-24v-200ah/

True, there are better prices by now. But 5kWh? I thought my smartphone would have that by now... Perhaps 200kWh is a bit exaggerated. And yes you also need a good quality inverter for your home that synchronizes with the net, but I actually don't believe this to be expensive high tech... Ideally I wouldn't want to put the energy I generate with solar, wind or differently back into the power net. In my country you ba…

Phone battery is something like 4V. Watts depend on voltage. I guess home batteries use other voltage so their watt actually provides more electricity.

Re: EVs Are Essential Grid-Scale Storage

#74

Post by dmurray »

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…

> 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.

If you can really treat the whole cost of the battery as X cents per charge cycle, disregarding the lifetime of the car/battery, this won't work at grid scale. Someone else will build a storage facility that just charges and discharges batteries, and they will outcompete rational EV owners, because they will have economies of scale and battery banks designed for this use. It only makes sense if the EV owner can somehow get charge capacity "for free" - eg the car will be EOL after 1000 charges but the battery lasts 2000 - he should sell the extra 1000. Or alternatively if getting 8c now is better than getting 1 charge in several years time (plausible if interest rates, energy futures prices etc are right).

However, this could be wrong. The same logic says rooftop solar can't exist without special subsidies, and a lot of people disagree with me there.

Re: EVs Are Essential Grid-Scale Storage

#75

Post by weard_beard »

martin-adams wrote: post #59
svggrfgovgf wrote: post #56

Earlier quoted context omitted.

People value things differently. You'd have to pay me way more than the 8 cents/kwh it cost me to use my battery. I'd want to be heavily compensated for the inconvenience of replacing the battery or car prematurely.

Plus the reduced range between new and replacement.

Plus my time and inconvenience of not having full range transport at all times. The time of someone who can currently afford an EV is more expensive than the time of someone who cannot.

Re: EVs Are Essential Grid-Scale Storage

#76

Post by shagie »

trashtester wrote: post #46
londons_explore wrote: post #25

Earlier quoted context omitted.

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…

> 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.)

https://www.tesla.com/sites/default/files/downloads/tesla-ne...

> Warranty Limitations

> This New Vehicle Limited Warranty does not cover any vehicle damage or malfunction directly or indirectly caused by, due to or resulting from normal wear or deterioration, abuse, misuse, negligence, accident, improper maintenance, operation, storage or transport, including, but not limited to, any of the following:

> ...

> Using the vehicle as a stationary power source

Re: EVs Are Essential Grid-Scale Storage

#77

Post by nickelcitymario »

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…

The way I read it, the paper is more interested in what happens to EV batteries when they drop to 80% of the maximum storage capacity. If I understood them, they're saying that at this level, the battery is no longer suitable for transportation purposes. So what do you do with the old battery when you replace it?

They're suggesting using these extremely expensive but no-long brand-new batteries for additional grid storage. Take the battery you don't use anymore, and instead of paying someone to dispose of it, plug it into the grid and get paid for its use.

Re: EVs Are Essential Grid-Scale Storage

#78

Post by dahfizz »

coffeebeqn wrote: post #71
dbingham wrote: post #58

Counter point, getting the resources for those batteries and building them has no small environmental impact - including carbon impact: https://www.theguardian.com/us-news/2023/jan/24/us-electric-... > The US’s transition to electric vehicles could require three times as much lithium as is currently produced for the entire global market, causing needless water shortages, Indigenous land grabs, and ecosystem destructi…

It’s not just cars. How would homes store energy overnight without lithium? The current best available home storage is still lithium based (lithium iron phosphate).

Why do houses need storage? Why can't the grid operators do their job?

Pumped hydro is a practical grid-scale storage solution that doesn't need lithium.

[1] cost $4B for 24Gwh of storage. That's about the same as the cost of an equivalent amount of batteries. But it has run for 37 years. A battery installment would have had to be replaced at least twice.

[1] https://en.wikipedia.org/wiki/Bath_County_Pumped_Storage_Sta...

Re: EVs Are Essential Grid-Scale Storage

#79

Post by tboyd47 »

baq wrote: post #32
tboyd47 wrote: post #19

So not only do the batteries lose 2.3% capacity each year, and lose up to 40% of their range in cold weather, but now the power company wants to drain your car battery at night to power other people's homes. What a comedy of errors!

Au contrarie, it’s a solution to bring grid storage online to offset some wind and PV intermittency.

That's just saying what I said in a different way.

Re: EVs Are Essential Grid-Scale Storage

#80

Post by dsfyu404ed »

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…

>Aren't people wary about using their very expensive car batteries for the grid?

EVs have mostly not yet filtered down to the socioeconomic rungs that have reason to be skeptical of things by default.

Based on what we know about EV battery lifetimes so far and how graceful their failure is I think your concerns are unfounded though.

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