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'Freeze-thaw battery' stores electricity long-term for seasonal release

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Re: 'Freeze-thaw battery' stores electricity long-term for seasonal release

#21

Post by gwbas1c »

phh wrote: post #7

It doesn't sound like the improvement of cost is enough the justify using it only for few cycles a year as the title says rather than every other day. That said, I see nothing in this article saying why it would be limited to seasonal release, I'm guessing it just has a lower self-discharge. The title made me thought of an idea my father had, for which I'm still totally ambivalent: Freeze water in the cellar (speakin…

Don't forget that, until the invention of refrigeration, people used to harvest ice in northern climates. They would store it in hay, and then sell it throughout the year.

Ice was even shipped internationally.

(And, if you're a fan of Disney's Frozen, this is exactly what Sven did.)

Re: 'Freeze-thaw battery' stores electricity long-term for seasonal release

#22

Post by snewman »

a9h74j wrote: post #17

Tangent, but in the seasonal storage context. Apparently, according to a reported simulation, if you (1) take a ca 15m x 15m house thermally in contact with the ground, (2) insulate the ground outside to a radius of ca 40m, and (3) heat the interior to say 25C, then (4) evenually (50years?) the ground itself under the house will come up to a steady temperature consistent with that. Even if the simulation was correct,…

Gradual heating of the ground is definitely a thing; over the decades, certain London Tube lines have drifted from pleasantly cool to sweltering: https://www.wired.co.uk/article/central-line-temperature-lon...

Re: 'Freeze-thaw battery' stores electricity long-term for seasonal release

#23

Post by gnorme »

a9h74j wrote: post #17

Tangent, but in the seasonal storage context. Apparently, according to a reported simulation, if you (1) take a ca 15m x 15m house thermally in contact with the ground, (2) insulate the ground outside to a radius of ca 40m, and (3) heat the interior to say 25C, then (4) evenually (50years?) the ground itself under the house will come up to a steady temperature consistent with that. Even if the simulation was correct,…

I'd love to read more about this simulation, have any links?

Re: 'Freeze-thaw battery' stores electricity long-term for seasonal release

#24

Post by [deleted] »

Gasp0de wrote: post #19

This doesn't seem cost efficient at all, my (medium sized) house in Germany consumes about 3000kWh of electricity during winter. This does not include heating, which consumes another 15.000kWh (of heat energy from oil, so around 5000kWh electrical energy with a heat pump). If I were to use this battery I would need to get 3000(8000)kWh of energy storage at 23$ per kWh which would amount to 69000(184000)$. There are b…

[deleted]

Re: 'Freeze-thaw battery' stores electricity long-term for seasonal release

#25

Post by bombcar »

mabbo wrote: post #10
phh wrote: post #7

It doesn't sound like the improvement of cost is enough the justify using it only for few cycles a year as the title says rather than every other day. That said, I see nothing in this article saying why it would be limited to seasonal release, I'm guessing it just has a lower self-discharge. The title made me thought of an idea my father had, for which I'm still totally ambivalent: Freeze water in the cellar (speakin…

> Freeze water in the cellar (speaking of like 30m^3) using thermal pomp during winter to heat house and when electricity costs little, and use that ice in summer to cool down the house. Unless I misunderstood, the Toronto Zoo has or had such a system setup for one or more of the food pavilions. What's interesting about this is that the storage grows with the volume (n^3), but the heat/cold loss grows with the surfac…

The cube/square law also applies in the opposite direction, this is why it takes longer for lakes to freeze and why the Great Lakes never do.

I believe at least one university on the Great Lakes does heating and cooling with pipes deep under the lake.

Re: 'Freeze-thaw battery' stores electricity long-term for seasonal release

#26

Post by mschuster91 »

KennyBlanken wrote: post #16
phh wrote: post #7

It doesn't sound like the improvement of cost is enough the justify using it only for few cycles a year as the title says rather than every other day. That said, I see nothing in this article saying why it would be limited to seasonal release, I'm guessing it just has a lower self-discharge. The title made me thought of an idea my father had, for which I'm still totally ambivalent: Freeze water in the cellar (speakin…

> some other people would have already proposed such things. Geothermal heat pumps. Been around for decades. Expensive to install due to drilling the well or laying the field, but very efficient.

Geothermal energy is risky AF though. Even with shallow drilling depths, you risk hitting anhydrite and, in combination with water, massive damage like in Staufen [1].

[1] https://de.wikipedia.org/wiki/Hebungsrisse_in_Staufen_im_Bre...

Re: 'Freeze-thaw battery' stores electricity long-term for seasonal release

#27

Post by pjc50 »

KennyBlanken wrote: post #15

Iron flow batteries already exist commercially, are even more non-toxic/safe, and they don't require heating up (and keeping hot, while using) the battery. https://essinc.com/iron-flow-chemistry/ The utility industry isn't really that interested in storing power for an entire season. Very little ROI compared to a system that allows them to balance minute-to-minute or day/night...or transmission infrastructure improve…

I've never really seen the advantage in going off grid per se, since it increases the amount of wasted capacity in both generation and storage, and running a few wires is cheap enough in urban environments. The most efficient arrangement might be a global grid.

Re: 'Freeze-thaw battery' stores electricity long-term for seasonal release

#28

Post by pjc50 »

Gasp0de wrote: post #19

This doesn't seem cost efficient at all, my (medium sized) house in Germany consumes about 3000kWh of electricity during winter. This does not include heating, which consumes another 15.000kWh (of heat energy from oil, so around 5000kWh electrical energy with a heat pump). If I were to use this battery I would need to get 3000(8000)kWh of energy storage at 23$ per kWh which would amount to 69000(184000)$. There are b…

The economics is not great as described, but I wouldn't see this at being an individual level solution. The larger it is, the easier it is to insulate.

Re: 'Freeze-thaw battery' stores electricity long-term for seasonal release

#29

Post by [deleted] »

mabbo wrote: post #10
phh wrote: post #7

It doesn't sound like the improvement of cost is enough the justify using it only for few cycles a year as the title says rather than every other day. That said, I see nothing in this article saying why it would be limited to seasonal release, I'm guessing it just has a lower self-discharge. The title made me thought of an idea my father had, for which I'm still totally ambivalent: Freeze water in the cellar (speakin…

> Freeze water in the cellar (speaking of like 30m^3) using thermal pomp during winter to heat house and when electricity costs little, and use that ice in summer to cool down the house. Unless I misunderstood, the Toronto Zoo has or had such a system setup for one or more of the food pavilions. What's interesting about this is that the storage grows with the volume (n^3), but the heat/cold loss grows with the surfac…

[deleted]

Re: 'Freeze-thaw battery' stores electricity long-term for seasonal release

#30

Post by brtkdotse »

phh wrote: post #7

It doesn't sound like the improvement of cost is enough the justify using it only for few cycles a year as the title says rather than every other day. That said, I see nothing in this article saying why it would be limited to seasonal release, I'm guessing it just has a lower self-discharge. The title made me thought of an idea my father had, for which I'm still totally ambivalent: Freeze water in the cellar (speakin…

Congratulations, you just invented geothermal heat pumps. :) They’ve been the preferred way of hearing single family houses in the Nordics since the 90s.
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