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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?

#271

Post by pfdietz »

kragen wrote: post #266
pfdietz wrote: post #262

Earlier quoted context omitted.

The critical temperature of water is 374 C.

You're right; I wonder why they operate supercritical steam turbines at 600° instead? https://direns.minesparis.psl.eu/Sites/Thopt/en/co/cycles-su... https://www.mdpi.com/2673-7264/5/1/1 https://www.modernpowersystems.com/analysis/is-700-c-steam-t... Oh, apparently because of "dramatic improvements in power plant performance": > Starting with the traditional 2400 psi / 1000 F (165 bar / 538 C) single-reheat cycle, dr…

Most coal plants in the US aren't ultrasupercritical. The first one only went operational in 2013, in Arkansas (the John W. Turk, Jr. Power Plant).

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

#272

Post by kragen »

pfdietz wrote: post #271
kragen wrote: post #266

Earlier quoted context omitted.

You're right; I wonder why they operate supercritical steam turbines at 600° instead? https://direns.minesparis.psl.eu/Sites/Thopt/en/co/cycles-su... https://www.mdpi.com/2673-7264/5/1/1 https://www.modernpowersystems.com/analysis/is-700-c-steam-t... Oh, apparently because of "dramatic improvements in power plant performance": > Starting with the traditional 2400 psi / 1000 F (165 bar / 538 C) single-reheat cycle, dr…

Most coal plants in the US aren't ultrasupercritical. The first one only went operational in 2013, in Arkansas (the John W. Turk, Jr. Power Plant).

Oh, really? What temperatures do US power plants operate their steam at?

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

#273

Post by overfeed »

adwn wrote: post #157
overfeed wrote: post #149

Earlier quoted context omitted.

> Having worked extensively with battery systems, I think the grid storage potential of second-life EV batteries is more complex than it appears. Complex, by t very much doable. Toyota implemented such a system with enough packs to power a Mazda factory [1] > However, you need to factor in significant integration costs (~$50-75/kWh) to build compatible BMS systems and thermal management. Shouldn't this be a once-off…

> Shouldn't this be a once-off cost per battery-pack version? A BMS isn't just software. It requires a µC, voltage and temperature sensors for cell monitoring, and power electronics for cell balancing. However, those are all comparatively cheap, especially at scale, and the quoted cost of 50–75 US$/kWh looks ridiculously overpriced to me.

I expect EV batteries to have all those components preinstalled already, and naively thought the grid-integration involves reverse engineering the battery's protocol, and perhaps bypassing/replacing a µC or 3.

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

#275

Post by Dylan16807 »

eldaisfish wrote: post #253
Dylan16807 wrote: post #250

Earlier quoted context omitted.

> the largest peak load is often an electric stove, which is regularly greater than 1,500 kW. Does that change anything about what I said? This is specifically about "if you do have supplementary house batteries". > Also, this idea that higher usage overlap with the sun being out is laughably wrong. The reason we have the duck curve is that insolation and demand largely overlap (especially when we're talking about th…

Everything you describe is true only in some places, likely California. In much of the rest of the world, electricity demand peaks in the evening, when the sun is low in the sky and continues well into the evening, when the sun isn’t out. Notice how even the Wikipedia page about the duck curve lists mainly California. Even in Australia and the UK, daylight hours and electricity demand mostly do not overlap.

>> The peak use is evening

> In much of the rest of the world, electricity demand peaks in the evening

Huh?

And again my chart showing that the entire day has much higher use than at night, then an extra high peak in evening, was Denmark.

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

#276

Post by pfdietz »

cyberax wrote: post #267
pfdietz wrote: post #257

Earlier quoted context omitted.

And nuclear is scalable if you force other sources off the grid in favor of nuclear (and force customers to not use renewables "behind the meter"). In a fair grid, solar and wind get built out, and the residual demand has no baseload component. Unless nuclear is given the right to force other sources off the grid it becomes inappropriate. In Texas now there is no chance of new nuclear construction. ERCOT is a competi…

> And nuclear is scalable if you force other sources off the grid in favor of nuclear (and force customers to not use renewables "behind the meter"). Not really? Nuclear is not any different from coal. And plenty of countries have coal generation in the mix. France also is majority-nuclear. And so far, nuclear is the second known technology (after hydro) that actually demonstrated close to 100% fossil-free grid. So f…

Nuclear is quite different from coal.

First, coal has a much larger share of its cost as variable cost which is avoided if you don't run the plant. 40% for coal, only 10% for nuclear. This makes integrated a coal fired plant into a renewable grid easier than a nuclear plant. China is increasingly doing this with its coal plants.

Second, coal is much more forgiving of maintenance sloppiness, and even in the event of catastrophic malfunction the plant remains repairable.

Nuclear has been available in its current (and no longer competitive) state longer than solar/wind have been in their current economic state, so if you look at historical data you might conclude nuclear is better. But that's backward looking and says little about what's better in the future.

You are aware that a nuclear plant tripping offline was part of the cause of ERCOT's last winter cold problem?

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

#277

Post by archi42 »

adwn wrote: post #181
SirFredman wrote: post #179

Earlier quoted context omitted.

And the nice thing is, prices will only get lower. They also have a 32.15kWh system for €3500,- which is insane.

Unfortunately, almost all three-phase [1] on-grid inverters that are on the market, especially hybrid inverters, only support batteries with much higher voltages, like 150 V or even more. [1] Three-phase wiring in homes seems to be very rare in the US, but is extremely common in Europe.

The trick is to get an inverter with a 48V battery interface, that's not locked down to a specific manufacturer.

But you're right, most installers do high voltage batteries.

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

#278

Post by pfdietz »

jopsen wrote: post #217
pfdietz wrote: post #49

Earlier quoted context omitted.

The low cost of the modules themselves has led to the suggestion of cost optimized DC-coupled PV systems being used to directly drive resistive heaters. The cost per unit of thermal energy in a cost optimized system moderate scale system (> residential, Low cost modules allow one to do away with things like optimally tilted modules and single axis tracking. The modules can also be tightly packed, reducing mounting an…

I've heard of farmers doing this, well I think they actually had an inverter. But limits on how much they could dump into the grid, meant that they had lots of surplus electricity and installing resistive heating was very cheap. Even if they don't have surplus electricity all the time.

Agriculture is one of the target markets for Standard Thermal. For example, grain drying is a large consumer of propane, which is expensive.

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

#279

Post by pfdietz »

kragen wrote: post #272
pfdietz wrote: post #271

Earlier quoted context omitted.

Most coal plants in the US aren't ultrasupercritical. The first one only went operational in 2013, in Arkansas (the John W. Turk, Jr. Power Plant).

Oh, really? What temperatures do US power plants operate their steam at?

Here's an article giving the state of such plants in the US in 2011. Since then I imagine some of the smaller/older plants have been retired. There is no new coal capacity coming online in the US.

https://www.powermag.com/coal-fired-generation-cost-and-perf...

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

#280

Post by thejazzman »

bryanlarsen wrote: post #251
floxy wrote: post #248

Earlier quoted context omitted.

The batteries in a hybrid are much smaller (~1.3 kWh for a Prius), and so cost much less to replace.

The vast majority of EV owners will spend $0 to replace their batteries since the batteries last longer than the rest of the car does. Edit: part of that is that a Prius with 250,000 miles needing its second battery replacement is still a valuable car with a reasonable expectation of a lot more miles. OTOH a Tesla at 250,000 miles needing its first battery replacement... Similarly Chrysler hybrid owners spend less mo…

My 2015 Model as’ battery went the day the warranty ended and so they gave me a trash refurbished one “half price” for $8k

This low maintenance cost thing is BS once something actually goes wrong. And it’s awfully frustrating / sus when it happens the moment the warranty ends

My 2017’s HV fuse went just days before the warranty ended. They tried to charge me $330 for that planned part.

These things aren’t cheap.

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