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Can “second life” EV batteries work as grid-scale energy storage?

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Re: Can “second life” EV batteries work as grid-scale energy storage?

#111

Post by bryanlarsen »

Dylan16807 wrote: post #65
epistasis wrote: post #27

Earlier quoted context omitted.

There's currently no technological path for fusion to be cheaper than fission. It would require a technological breakthrough that we have not yet imagined. And already, solar plus storage is cheaper than new nuclear. And solar and storage are getting cheaper at a tremendous rate. It's hard to imagine a scenario where fusion could ever catch up to solar and storage technology. It may be useful in places with poor sola…

Fission is expensive for regulation reasons more than technological reasons, so if fusion doesn't face the same barriers then it could be cheaper than fission. But I agree that it doesn't look like fusion is going to be cheap any time soon.

Fission is also expensive for several mundane reasons, like the fact that massive steam turbines are expensive, and because any large construction project in the West is expensive. Neither fusion nor regulatory reform are going to solve those.

Re: Can “second life” EV batteries work as grid-scale energy storage?

#112

Post by nandomrumber »

apendleton wrote: post #102
pfdietz wrote: post #84

Earlier quoted context omitted.

High temperature superconducting magnets are not a panacea for the problems with DT fusion. Those issues follow from limits on power/area at the first wall, and the needed thickness of the first wall; these ensure DT reactors will have low volumetric power density, regardless of the confinement scheme used. With HTSC magnets, a tokamak much smaller than ITER could be built, but ITER is so horrifically bad that one ca…

Oh for sure, I'm not claiming that CFS (or Tokamak Energy or Type One or whoever else) will for sure succeed, or if they do, that they've already solved all the problems that will need solving to do so. My only assertion/prediction is that I think if they end up succeeding, when future historians look back and write the history of this energy revolution or whatnot, HTSC magnets will turn out to have been the key brea…

Fusion reactors are self destroying, just ask any star.

More seriously: what to do about the neutron flux destroying the first wall inside the reactor vessel?

Re: Can “second life” EV batteries work as grid-scale energy storage?

#115

Post by nandomrumber »

torginus wrote: post #64
irons wrote: post #44

Earlier quoted context omitted.

In the US, V2L limits your ability to output power from the car to about 1500 W. It's not going to power your house as more than a stopgap, even if you do have supplementary house batteries. V2H/V2G justify their complexity by solving that problem, along with all the ancillary grid benefits.

Not sure if that's the case - however doing V2L requires the manufacturer to add an inverter to the car, and making that powerful probably adds extra cost most customers wouldn't pay. TI just looked it up and my Ioniq can only do about 2kW sustained - but since this charges the house battery, that's enough - idle load is just a couple hundred watts.

If the car charges the house battery, what charges the car?

Re: Can “second life” EV batteries work as grid-scale energy storage?

#116

Post by trhway »

nandomrumber wrote: post #109
trhway wrote: post #32

Earlier quoted context omitted.

Prius Plugin 2015 (last year of that model) - full charge/discharge at least 3-4 times a week, currently still a bit more than 80% of capacity (granted the battery seems somewhat overbuilt, yet it is normally does 10-15C which is much tougher mode than in a pure EV where 2-3C is usually enough and only high-end Teslas and the likes would do 5-6C). There has been large continuous improvement in lithium batteries over…

What does any of this mean? What is c in this context?

1 C current fully discharges battery in 1 hour. Thus 4KWh battery running 60 KW engine means 15C current, and it would discharge the battery in 4 minutes (in a very simplified linear model).

Re: Can “second life” EV batteries work as grid-scale energy storage?

#117

Post by dtgriscom »

nandomrumber wrote: post #109
trhway wrote: post #32

Earlier quoted context omitted.

Prius Plugin 2015 (last year of that model) - full charge/discharge at least 3-4 times a week, currently still a bit more than 80% of capacity (granted the battery seems somewhat overbuilt, yet it is normally does 10-15C which is much tougher mode than in a pure EV where 2-3C is usually enough and only high-end Teslas and the likes would do 5-6C). There has been large continuous improvement in lithium batteries over…

What does any of this mean? What is c in this context?

From my model airplane experience, I believe it's "capacity per hour". So, a 1Ah battery discharged at 1c would mean 1 amp; discharged at 10c would be 10 amps. The higher the C, the harder the batteries are being used.

Re: Can “second life” EV batteries work as grid-scale energy storage?

#118

Post by nandomrumber »

Dylan16807 wrote: post #74
irons wrote: post #44

Earlier quoted context omitted.

In the US, V2L limits your ability to output power from the car to about 1500 W. It's not going to power your house as more than a stopgap, even if you do have supplementary house batteries. V2H/V2G justify their complexity by solving that problem, along with all the ancillary grid benefits.

A typical house averages less than 1500W. And most of the higher usage overlaps the sun being out. So if you have supplemental house batteries to handle bursts then 1500W of V2L can go a very long way.

> And most most of the higher usage overlaps the sun being out.

Aren’t most people at work / school when the sun is out?

Re: Can “second life” EV batteries work as grid-scale energy storage?

#119

Post by rgmerk »

numpad0 wrote: post #93
pinkgolem wrote: post #28

Earlier quoted context omitted.

i have heard that hybrid's have a maintanance problem? is not a concern, double the technologie in the same space?

It's not like reliable gas cars ever had substantial maintenance problem in the gas part. So removing the gas part didn't do much in practice. People do/did have frustrations with gas car mannerisms and mental approachability, like, everything was written in a mix of translated foreign language documents and borderline insane gearhead languages. That lead them to imagine that removing the gas part would drastically c…

Reliable gas cars still require a lot more maintenance than an EV does.

Oil and oil filter changes. Fuel filters. Air cleaners. Brake pads (that mostly goes away with hybrids too).

Re: Can “second life” EV batteries work as grid-scale energy storage?

#120

Post by epistasis »

apendleton wrote: post #103
epistasis wrote: post #94

Earlier quoted context omitted.

And these are not new issues, they've been known for more than 40 years, but never addressed. From the 1983 Led > But even though radiation damage rates and heat transfer requirements are much more severe in a fusion reactor, the power density is only one-tenth as large. This is a strong indication that fusion would be substantially more expensive than fission because, to put it simply, greater effort would be requir…

In terms of cost of materials to build a reactor, sure, that seems right. But most of the cost of fission is dealing with its regulatory burden, and fusion seems on track to largely avoid the worst of that. It seems conceivable that it ends up being cheaper for entirely political/bureaucratic reasons.

Regulatory costs and waste disposal are not significance cost centers for nuclear, at least as far as I can tell from any cost breakdowns.

One doesn't need super high quality welding and concrete pours becuase of regulations as much as the basic desire to have a properly engineered solution that lasts long enough to avoid costly repairs.

Take for example this recent analysis on how to make the AP1000 competitive:

https://gain.inl.gov/content/uploads/4/2024/11/DOE-Advanced-...

There are no regulatory changes proposed because nobody has thought of a way that regulations are the cost drivers. Yet there's still a path to competitive energy costs by focusing hard on construction costs.

Similarly, reactors under completely different regimes such as the EPR are still facing exactly the same construction cost overruns as in the rest of the developed world.

If regulations are a cost driver, let's hear how to change them in a way that drives down build cost, and by how much. Let's say we get rid of ALARA and jack up acceptable radiation levels to the earliest ones established. What would that do the cost? I have a feeling not much at all, but would like to see a serious proposal.

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