Cold without the compressor: Boffins build better ice box

Scientists at Johns Hopkins and Samsung have developed a nano-engineered thermoelectric material that is twice as efficient at material-level cooling as existing alternatives, paving the way for broader adoption of solid-state refrigeration technology. Commercial refrigeration and air conditioning tend to use compressors that …

[DS999]

Being twice as efficient at material level cooling

As previous technology does not equal replacing compressors. I've seen this technology mentioned in several articles recently, but none that directly compare it to the efficiency of modern cooling compressors. Unless it can beat them on efficiency, price or longevity it might have some roles in stuff like chip cooling, but won't be keeping your meat cold anytime soon.

[lnLog]

Re: Being twice as efficient at material level cooling

This^

[david 12]

Re: Being twice as efficient at material level cooling

Thermo-electric materials are *already* used to keep meat cool I've got a travel cooler. We, and people like us, use them for meat when traveling.

It uses more power (is less efficient), but is robust.

[Richard 12]

Re: Being twice as efficient at material level cooling

Existing thermoelectric cooling barely works at all.

In almost all cases you're better off simply adding sufficient cold thermal mass to an insulated box.

[LBJsPNS]

Re: Being twice as efficient at material level cooling

And remember, you can't beat cold meat!

[ravenviz]

Re: Being twice as efficient at material level cooling

Breaking the paradigm, no meat beats cold meat.

[Chris Gray 1]

Excellent!

Good progress. Even better would be more progress.

Also, I've thought for years that direct thermal power generation would be a godsend. It already exists, but not for practical use. The article here mentions that the "CHESS" stuff works for it too. Here's hoping that that aspect can be made practical.

[vogon00]

Re: Excellent!

"Good progress. Even better would be more progress."

Burst out laughing at this. People around me probably thinks I need psychiatric help.

Who knows, they may be right:-)

[Charlie Clark]

Re: Excellent!

Direct thermal power generation, ie. the thermal equivalent of the photoelectric effect, is very inefficient and not really worth pursuing when you look at the efficiencies of steam turbines, driven by the sun. You can use the same mechanism and enegry to drive compressors which, with alkanes as refrigerants, have greater efficiencies and thermal ranges than conventional ones. It's just that very little research is being done on what else you can do with the energy – I'm personally certain that self-contained hydrocarbon systems could be driven almost entirely using solarthermal energy.

[Paul Hovnanian]

Re: Excellent!

Absorption Refrigeration. Commonly used in RVs and campers. Not as efficient as mechanical heat pumps. But multi-stage versions exist which operate over greater temperature ranges. And, if the heat source is 'free', they can be quite economical. Free often being lower grade (delta T) heat sources than are suitable for turbines, such as waste industrial heat or solar.

[Pascal Monett]

So, one step closer

We're getting one step closer to the nanosuits in Crysis.

<cue Evil Genius cackling>

[Muscleguy]

Re: So, one step closer

Or the stillsuits in Dune.

[Neil Barnes]

Is it just me?

Or is it suddenly cool in here?

[Phil O'Sophical]

Re: Is it just me?

We do our best.

[Champ]

Room temperature?

Am I misreading this?

"...was almost 100 percent more efficient at room temperature (300 K, ~80°F, ~27°C) than other thermoelectric materials"

If room temp is -27C at your place, I'm not coming to visit

[Pantagoon]

Re: Room temperature?

You are misreading it. The symbol before 27 is a tilde, not a minus. It means 'about'.

[Andy E]

Re: Room temperature?

So it could be hotter or cooler than 27C?

[Captain Hogwash]

Re: Room temperature?

But not by much.

[ravenviz]

Re: Room temperature?

±

The post is required, and must contain letters.

[Anonymous Coward]

Re: Room temperature?

You are misreading it.

Yes, maybe the author of the post you are commenting on misread it.

And then maybe not: the tilde is quite identifiable.

That said, if room temp is ~27° C at your place, I'm not coming to visit either.

Room temp above 25° C can start to get uncomfortable quite fast for my species*.

* keyboard gerbil

.

[bernmeister]

Re: Room temperature?

Summer time temperatures at, Laurel, Maryland location can reach 27C all day during the summer. Perhaps their lab has no air conditioning or is a Portacabin in the grounds. Poor guys, they must sweat a lot during the summer, hence their preoccupation with cooling devices.

[rcxb]

Re: Room temperature?

Poor guys, they must sweat a lot during the summer

What? 27C is far below body temperature. You're just poorly dressed if you aren't comfortable at those temperatures. In fact it is just a hair warmer than normal comfortable summer time office temperatures (23-25C).

[GlenP]

Re: Room temperature?

I just looked and the digital thermometer in my home office in the East Midlands of the UK is showing 27.5°C which is probably about right for a reported outside temp of 25°C. The fan is helping make it feel a bit cooler!

[Andrew Scott]

Re: Room temperature?

33 C here right now and supposed to get hotter. don't know the inside temp at work, but no air at home as the house doesn't lend itself to window air conditioners. Believe thy use co2 for heat pumps in some places. less toxic than some refrigerants and less flammable than others, and less ozone depleting than most. high pressure plumbing though.

[Vincent Ballard]

Re: Room temperature?

But I will. My infrared thermometer currently reads 30.9 in my living room.

[xyz]

Isn't this the plot of The Matrix?

CHESS materials are also able to convert temperature differences, like body heat, into usable power,”

[Grunchy]

Re: Isn't this the plot of The Matrix?

The premise of the Matrix movie is that people are held inert so that computers can power themselves from body heat, ignoring completely the vast HVAC power needs to maintain liveable environments. It was the flimsiest premise I ever saw, well, except for Bill and Ted Excellent Adventure, of course.

[John Brown (no body)]

Re: Isn't this the plot of The Matrix?

Even worse, the concept of people "living" in an artificial reality was stolen from Doctor Who where expired time Lords (and all knowledge) was stored in an artificial reality called...The Matrix.

[John Robson]

Re: Isn't this the plot of The Matrix?

It was "combined with a form of fusion"... my first thought was, well if you've got fusion, you don't need fleshy AAs

[DanielsLateToTheParty]

Every dichotomy is a false dichotomy

The third type of refrigeration is https://en.wikipedia.org/wiki/Absorption_refrigerator

Often overlooked, it has no moving parts and uses heat directly as a power source. Of course the laws of thermodynamics apply and you cannot get more cold out than the heat you put in. Occasionally I wonder if this could be used as a pre-cooler for computer enclosures? The air blown over chips would be cooler than ambient and the exhaust feeds back into the heat cycle.

[I could be a dog really]

Re: Every dichotomy is a false dichotomy

Yes, absorption cycles work - it's the basis (for example) of the gas powered fridges used in caravans. But again, not very efficient compared to a compressor system.

[Chris Gray 1]

Re: Every dichotomy is a false dichotomy

My parents had a small holiday trailer (caravan) when I were a young 'un. Boggled my mind that burning propane made the inside of the little fridge cold!

[John Brown (no body)]

Re: Every dichotomy is a false dichotomy

"Yes, absorption cycles work - it's the basis (for example) of the gas powered fridges used in caravans. But again, not very efficient compared to a compressor system."

On the other hand, if off grid in caravan and running it from roof mounted solar panels, does efficiency matter all that much so long as you are generating enough power for your needs?

[Crypto Monad]

Re: Every dichotomy is a false dichotomy

Yes, because there are days (or even weeks) when solar generation drops to almost zero. The efficiency of your refrigerator directly translates into how many hours before it cuts out because your battery is empty.

[Paul Hovnanian]

Re: Every dichotomy is a false dichotomy

Not refrigeration for food preservation. Air conditioning. When the sun isn't out, the demand for AC is much less.

[I could be a dog really]

Re: Every dichotomy is a false dichotomy

Well if you were going off-grid running from solar panels - run a compressor. You can buy small ones for travel use.

[Christoph]

This might have been excellent for cooling Infra-red telescopes in space. Oh well, maybe the Chinese can use it as they still have a space program.

[Muscleguy]

Hmmm

When’s it going to replace the compressor and the ethylene glycol being pumped by my heat pump system? Also can it work the other way like my heat pump can? Instead of cooling can it heat? Or maybe replacing the air heater for cold days it uses.

[Ian Mason]

Re: Hmmm

Yes Thermoelectric Coolers (TECs) are reversible, and can heat as well as cool, just apply the electric current the other way around.

TECs efficiency however is terrible, under ideal conditions it's hard to achieve a COP (Coefficient Of Performance) of more than one, meaning you have to supply as much or more energy as heat you want to move whereas the humble domestic refrigerator has a COP in the rough region of 3, meaning that for every Joule of energy that you want to move you only have to supply about 1/3 of a Joule to do the moving.

[ravenviz]

Indeed, as about as resource hungry as using livestock for food.

[Bartholomew]

removing the heat added is the major problem with thermoelectric cooling

> almost 100 percent more efficient at room temperature (300 K, ~80°F, ~27°C) than other thermoelectric materials.

Since the current TEC is about 5% to 15% efficient (near room temperature), as in 5% to 15% of the power applied ends up cooling and 95% to 85% ends up being additional heat that needs to be removed.

Traditional compressor based refrigeration this efficiency is typically 40% to 60% and any waste heat generated is nowhere near the item being cooled.

Even if 10% to 30% efficient (near room temperature), this new cooling technology will not be a compressor replacement technology, but it is getting closer.

[John Brown (no body)]

Coincidently....

Coincidently, I just watched that Hannah Fry documentary The Secret Genius of Modern Life episode on refrigeration and at the very end is a guy who has built a working fridge using materials which change temp in a magnetic field. Not sure if it's actually in production yet, but is built to fit a standard fridge compressor space and rotates magnets around the centre column and gets the temp. down to about 4c, ie fridge, not freezer temps. Not sure of the efficiency and the clip showed a "mini-bar" type fridge as seen in hotels. Heat transfer via is piped water. The USP is no "harmful" refringent such as CFCs, HFCs, or flammable isobutane. But, of course, it's electromechanical to keep the magnets spinning, so still has moving parts that can wear out.

Ah, found them here, camfridge.com/ and some youtube videos by searching magnet cooled fridge

[Bartholomew]

Re: Coincidently....

Camfridge use magnetocaloric materials and the magnetocaloric effect for cooling.

The fundamental technology has been about a very long time (first observed in 1881), General Electric (with help from the Oak Ridge National Laboratory) planned to bring it to the consumer market in 2020 (looks like they missed that date and then some). Here is a video recorded in Oak Ridge National Laboratory https://www.youtube.com/watch?v=z9ThxbAyIB8 that claims that it might be 25% more efficient then compressor based colling.

Here is a far more interesting GE video ===>>> https://www.youtube.com/watch?v=UpogxBxbPPo <<<===

Most of the high end magnetocaloric materials used are based around the rare earth element gadolinium, and then you have a bunch of other rare earth elements in the high power magnets. In short it will be expensive, and if the consumer market grows the cost will not go down, in fact it drive up the price of other existing items that use rare earth magnets (e.g. electric cars, wind turbines, ...).

[Anonymous Coward]

Beer cans?

Given this material is rather thin, I was thinking that each beer can could be coated with it and your can could be placed on a usb3 powered can cooler dock to keep your beer cold.

Rather amusing reading comments that considered 25°C hot. In our neighbourhood for a decent part of the year 25°C would not be an unusual overnight minimum or winter maximum.

Beer at ambient is undrinkable particularly if that is 35°C.