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antiatheist
"temperature lift as high as 25°C using a voltage strength of ~0.22 volts."

Sounds impressive, but I know little about the field, and don't have access to the full paper.

What kind of ionic solution are they using?

RandomWorker
Supplement material contains everything even the material selection method, what they used as materials, modelling results, and a design of the device used.
0x5345414e
So it’s a solid and it melts, absorbing heat, then it must turn back into a solid, releasing heat. I’m curious to see how they move the solid back to where it started to complete the cycle. Maybe the material doesn’t move at all, it’s on some kind of revolving assembly? It’s just that in modern refrigeration systems, the evaporator isn’t necessarily that close to the condenser, so with a solid I can see this being awkward in some situations.
piyh
Refrigerant pellets could be transferred like grain or wood pellets. Augurs, conveyors, or pneumatic.

If you could get it to solidify into a powder or partially solidify you could come up with alternatives, but you'd get in trouble with frozen lines.

moloch-hai
The heat could be moved around via a different liquid or gas that does not need to undergo phase change.
moloch-hai
Adding that water and propylene glycol have been used for this in a few places, e.g. a half-billion cars.
0x5345414e
True, that’s pretty common in industrial and commercial settings as well. Though here I’m thinking more in terms of a residential setting. Relying on a secondary fluid loop would likely raise the cost quite a bit due to the extra components required.

They’ve raised the global warming issue about current refrigerants but what really matters is the economics of isocaloric vs. vapor compression because there are more modern refrigerants[1] that have quite low global warming potential. It makes that argument carry less weight than it used to imo.

[1] See R455A, R1234ze, R515B, for example.

RandomWorker
You have two of them or more in the assembly, you fully saturate one side, and desaturate the other. Then you switch the direction you pump. You have losses in heating and cooling the respective sides.
yarg
This once again has me wondering about quantum dots - wondering if quantum dots can be used for refrigeration (there're papers as far back as '93).

I figured they'd have to be infrared, and then I got distracted by the difficulties producing dots that large[1].

It seems that there's been some trouble scaling up to that scale (though scaling down into the UV would be even more problematic).

[1] - https://www.osti.gov/servlets/purl/1500079

NGC404
That is indeed interesting to think about. What exact mechanism did you had in mind for thermal energy transport?
yarg
Electrical. Probably very naïve of me.
kragen
is this on a preprint server or something anywhere

the website only wants to show me the abstract

xenonite
Is it adequate to use this method for heating?