Scientists Invent an Entirely New Way To Refrigerate Things (sciencealert.com) 55
"Say hello to ionocaloric cooling: a new way to lower the mercury that has the potential to replace existing methods with something that is safer and friendlier to the planet," writes ScienceAlert.
It's all based on the idea that melting absorbs heats. "The landscape of refrigerants is an unsolved problem," says mechanical engineer Drew Lilley, from the Lawrence Berkeley National Laboratory in California. "No one has successfully developed an alternative solution that makes stuff cold, works efficiently, is safe, and doesn't hurt the environment. We think the ionocaloric cycle has the potential to meet all those goals if realized appropriately...."
A current running through the system would move the ions in it, shifting the material's melting point to change temperature. The team also ran experiments using a salt made with iodine and sodium, to melt ethylene carbonate. This common organic solvent is also used in lithium-ion batteries, and is produced using carbon dioxide as an input. That could make the system not just GWP [global warming potential] zero, but GWP negative.
A temperature shift of 25 degrees Celsius (45 degrees Fahrenheit) was measured through the application of less than a single volt of charge in the experiment, a result that exceeds what other caloric technologies have managed to achieve so far.... "Now, it's time for experimentation to test different combinations of materials and techniques to meet the engineering challenges," says mechanical engineer Ravi Prasher, from the Lawrence Berkeley National Laboratory.
Thanks to long-time Slashdot reader schwit1 for sharing the article.
It's all based on the idea that melting absorbs heats. "The landscape of refrigerants is an unsolved problem," says mechanical engineer Drew Lilley, from the Lawrence Berkeley National Laboratory in California. "No one has successfully developed an alternative solution that makes stuff cold, works efficiently, is safe, and doesn't hurt the environment. We think the ionocaloric cycle has the potential to meet all those goals if realized appropriately...."
A current running through the system would move the ions in it, shifting the material's melting point to change temperature. The team also ran experiments using a salt made with iodine and sodium, to melt ethylene carbonate. This common organic solvent is also used in lithium-ion batteries, and is produced using carbon dioxide as an input. That could make the system not just GWP [global warming potential] zero, but GWP negative.
A temperature shift of 25 degrees Celsius (45 degrees Fahrenheit) was measured through the application of less than a single volt of charge in the experiment, a result that exceeds what other caloric technologies have managed to achieve so far.... "Now, it's time for experimentation to test different combinations of materials and techniques to meet the engineering challenges," says mechanical engineer Ravi Prasher, from the Lawrence Berkeley National Laboratory.
Thanks to long-time Slashdot reader schwit1 for sharing the article.
Wonder which will be viable first? (Score:2)
Re: Wonder which will be viable first? (Score:2)
Not a serious article (Score:3)
Fusion or Ionocaloric Cooling. Going to be a leap forward when it happens!
It's hard to take the article seriously when "a new way for cooling" prominently talks about its global warming potential (and not, for example, how well it works), and references a single volt of charge.
It's an interesting idea, but seems seriously scammy.
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The article is poorly written and that's only one example. The actual research is published in Science as is probably much more informative and well written.
It's only scammy in that it is written for clicks.
I don't have access to Science at the moment but the abstract seems reasonable enough. The interesting part would be the analysis to see if they think that this is something that could easily move from research to production or if more research is necessary. From TFA, a researcher is quoted as saying, "F
"Single volt of charge"? (Score:5, Insightful)
Headline *and* article are nearly meaningless. I'm sorry, LBNL; someone at sciencealert let a chatbot write an entire article.
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How close (Score:2)
TANSTAAFL (Score:2)
Re:TANSTAAFL (Score:5, Informative)
Eh? What on earth are you talking about? No one's claiming this is a magical free energy device. It's a new kind of heat pump so of course it needs energy in.
You shift ions in, it melts getting cold. Then you shift ions out and it freezes, getting hot and you dump the heat. And repeat the process. Shifting the ions requires energy.
Better source for TFA (Score:5, Informative)
Here's a better source and explanation [Ars Technica]:
https://arstechnica.com/scienc... [arstechnica.com]
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In normal refrigeration phase change is from gas to liquid and back. Both can be pumped easily. Here the phase change is melting, not easy to pump. It was confusing to me. So looks like they will use another fluid to transport heat.
Re: Better source for TFA (Score:3)
A lot of commercial systems already use something like water/glycol.
A lot of new heat pumps are "monobloc" where the entire unit is outside and the only thing coming in is heated/cooled water
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Ars Technica is the place where original articles are posted and slashdot is the parasite where they get reposted.
You got to love slashdot (Score:1)
SCIENTIST INVENT A NEW WAY TO REFRIGERATE
Summary: Ice is cold
You got to love how they write this stuff.
A good book (Score:5, Informative)
If you're interested in the history of scientists chasing cold, "Absolute Zero and the Conquest of Cold" by Tom Shachtman is an interesting read.
Beginning in 1620 when Cornelis Drebbel cooled Westminster Abbey, the book follows the exploration of lower & still lower temperatures, liquefying gasses, and some of the effects ultra-cold can have on various materials. The invention & refinement of the thermometer is covered along with the natural ice industry & commercial refrigeration.
Anyway... if you enjoy science history you may want to give this book a look.
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There is a fascinating episode (or multiple) of some PBS show that goes over all this.
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I thought PBS had pretty much been given over to Deepak Chopra selling his shtick.
Re:A good book (Score:5, Informative)
Found it on YouTube:
Part 1
https://www.youtube.com/watch?... [youtube.com]
Part 2
https://www.youtube.com/watch?... [youtube.com]
Mod Parent Up (Score:2)
Found it on YouTube: Part 1 https://www.youtube.com/watch?... [youtube.com] Part 2 https://www.youtube.com/watch?... [youtube.com]
I can confirm that watching this doc is definitely worth the time; when I watched it years ago, I had no idea that someone harvested ice from the Great Lakes and shipped it to India. It's also a good study case for the scientific method.
https://news.slashdot.org/comm... [slashdot.org]
Common organic solvents (Score:1)
Cooling is reversing entropy. It is going to require multiple times the energy displaced. I bet there is a formulation for the maximum efficiency. I bet we are getting close.
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It is going to require multiple times the energy displaced.
Um, no [wikipedia.org].
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Re:Common organic solvents (Score:5, Informative)
It is going to require multiple times the energy displaced.
No, it's the other way around. You can use a small amount of energy to move a large amount of heat. Good heat pumps have a coefficient of performance of over 4, meaning 4 joules moved from the cold source to the hot source (or the other way around) for every 1 joule put in.
I bet there is a formulation for the maximum efficiency.
There is: the Carnot efficiency
https://www.e-education.psu.ed... [psu.edu]
I bet we are getting close.
Not especially, but not too bad. Plug the output and input temperatures of your favourite heatpump or fridge into the formula and see how it compares to the quoted coefficient of performance.
Cool (Score:3)
Cool
Contradictions and Vagueness (Score:2)
So, the summary above talks about a 25 degree shift,but the summary on the Science website (where the paper is published) says a "25 degree lift " which, unless I'm much mistaken, is heating not cooling.
Further, neither suggests either an actual start- or end-point for this 25 degree change - which makes me suspicious. If this process works in a zone close to zero degrees Celsius, why not say so at the outset?
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Lift is the difference between the cold reservoir and the hot reservoir. Think of cooling as pumping heat up hill.
Thermodynamic Suicides True (Score:1)
https://imgur.com/rL7PLWu [imgur.com]
https://en.wikipedia.org/wiki/... [wikipedia.org]
https://en.wikipedia.org/wiki/... [wikipedia.org]
https://www.reddit.com/r/today... [reddit.com]
let's debunk this (Score:1, Interesting)
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There is something to be said if you can maintain the same levels of efficiency, but use more environmentally friendly coolants. Ask anyone who works on cars regularly and they can tell you that working on A/C (legally at least) can be a real pain because of all the regulations that exist because A/C coolants are such nasty greenhouse gases (and ozone destroyers in older cars). Of course, each generation of automotive coolant has gotten better. R12 was 10,000 times worse than CO2 as a greenhouse gas (plus i
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r290 (propane) might also be a good choice. Certainly flammable, but the GWP is 3 and 0 ozone depletion. Nowhere near the pressure of CO2 required in operation. We already allow multiple kilos of it to be carried around in a car.
U.S. standards are hampered by industry's desire for something patentable, which will also be a factor for CO2.
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r290 (propane) might also be a good choice. Certainly flammable, but the GWP is 3 and 0 ozone depletion. Nowhere near the pressure of CO2 required in operation. We already allow multiple kilos of it to be carried around in a car.
It is a lot more flammable than r1234yf though. There's a study of flammability of r290 vs. r1234yf here [royalsocie...ishing.org]. They had trouble getting the r1234yf flame lit and had to use the propane flame to light it. Of course, burning propane doesn't produce toxic gas, just water vapor and CO2 whereas burning r1234yf does produce toxic gas (although apparently only mildly so). So, tradeoffs all around. Ultimately, if all it means is heavier duty tubing and components, a CO2 system seems ok to me, as long as it's not actuall
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With refrigerators, the concept is coefficient of performance (heat transferred/work), not efficiency. You can get a COP of well over one (with a theoretical limit equal to the Carnot_cycle [wikipedia.org]). The Carnot cycle is expressed in terms of a fluid, but the result is a limit imposed by the second law of thermodynamics and is independent of the process.
The theoretical limit of COP depends on the ratio of absolute temperatures of the hot and cold reservoirs and approaches infinity as as that ratio approaches 1.
Re:let's debunk this (Score:4, Informative)
Modern compressor coolers of any kind from AC window units to fridges are generally 94%+ efficient.
What do you mean by 94% efficient? That's not generally meaningful for a heat pump. The CoP is how much energy is moved from the cold source to the hot source for every unit of energy expended, and is normally much greater than 1 (4 or so) for most domestic level temperature differentials. The maximum CoP theoretically possible is the Carnot efficiency.
"94% efficient" doesn't mean anything. Maybe you mean within 0.94 of the Carnot efficiency, but that strongly depends on the temperature differential.
this nonsense reads like a perpetual energy from the universe because exotic chemistry scam article.
There's a certain irony in saying that. There seems to be a bit of a trend for angry nerds to call anything they don't like or don't understand a "scam". This is not a scam, it's a paper, and you clearly don't know what you're talking about.
Re:let's debunk this (Score:4, Interesting)
There are ways to add to the compressor, and add more efficiency. This video comes to mind. Of course there needs a way to move the refrigerant, but with this system, it could be heated by solar without the need of PV cells, as solar heating is a lot more efficient. Or, could be done by other means, be it natural gas, etc. [youtube.com]
The problem with A/C right now is that in general, it requires electricity and lots of it to power a compressor. Having some way to power the heat engine can help greatly, especially in climates where one could use solar magnification to generate heat to push the refrigerant, as opposed to a mechanical pump.
It would be nice to see Einstein-cycle A/C systems. However, the closest we have to this are absorption refrigerators in RVs. They do work, but they definitely are not going to get your beer chilled quickly, compared to a compressor fridge running from a solar panel and batteries. It also has issues with needing to be level.
Overall, any new developments in refrigeration are important ones. This is something that is going to be more and more critical as things go on.
What's wrong with R600a, with minimal GWP? (Score:2)
It's in all new (non-Peltier cooled) U.S. residential refrigerators, by law.
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This article was clearly written by someone who has only heard about how refrigerators work and vaguely remembers something about "Freon." Modern refrigerants are quite safe.
Re:What's wrong with R600a, with minimal GWP? (Score:5, Informative)
This article was clearly written by someone who has only heard about how refrigerators work and vaguely remembers something about "Freon." Modern refrigerants are quite safe.
Indeed. And there are also modern fridges based on the magnetocaloric effect. I have one. They are quieter, consume less energy and probably live a lot longer as they have almost no moving parts and there is no refrigerant in them at all.
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Actually, I do not have one (it is R600a, not stated in the manual and no flammability warnings, had to look at the somewhat hidden label in the machine), but cooling appliances based on that approach have been demonstrated in the last few years. So there are definitely non-refrigerant approaches, contrary to the claim made. Peltier would be another one, but it is hugely inefficient.
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Indeed. And there are also modern fridges based on the magnetocaloric effect. I have one.
Name one.
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Where did you go to school?
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R600a is isobutane, no? It's flammable.
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Yep. If you mix the amount in a typical fridge _very_ carefully with air, it may just be enough to blow the fridge door off. A typical gas-stove is a massive, massive risk in comparison.
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Might not see gas stoves much longer.
"A single volt of charge"? (Score:2)
That doesn't tell us anything about the total input power for the system.
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It also doesn't tell us anything about the amount of heat being transferred. Was that just a change between the hot side and cold side of the cooling system with no load, or were they cooling down 1 ml of water, 1 litre of water or a cubic meter of water?
Reporters who can't convey meaningful information in a science report should either refrain from reporting on stories like this, or have their credentials withdrawn.
It's like reporting that someone died on Tuesday, but failing to mention where it happened,
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It's weird phrasing! I would only say "as single X" if X was a) something that came in integral quantities and normally came in lots. For example I might ask for a single egg when they are normally sold in dozens, but "volt" is a unit for a continuous quantity. What is wrong with "less than one volt" or event "just one volt"?
That still wouldn't tell us the power, of course, but that presumably depends on how much heat is being moved and you could parallel up to any scale.
Not true (Score:2)
There are alternative cooling methods. For example, I have a fridge that uses the magnetocaloric effect (basically a wheel rotating in a magnetic field) and it does consume less power and as far as I can determine the environmental effect is also not a problem. Should also have a far longer lifetime due to less moving parts. The only difference for the user is that it is quieter and there is a small circulation fan inside my fridge as the cooled area is smaller.
That this effect is suspiciously omitted from
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I thought magnetocaloric refrigeration was still in the lab?
30% more energy efficient and liquid coolants that don't pose any environmental threat seems like an easy sale.
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Oops, you are right. This is the most quiet and efficient R600a fridge I have ever used and apparently the legal requirement to state the refrigerant in the manual does not hold for R600a here under some conditions. It had to look at the labe on the fridge (somewhat hidden) to find out. There is also no flammability warning in the manual, probably because the amount of coolant is too small. Hence I was fooled as to mine, my apologies.
That still leaves the original point intact and we are probably going to s
It will be all about energy efficiency (Score:4, Insightful)
Refridgerate isn't best choice of terms (Score:2)