This is a most excellent place for technology news and articles.
Im sure that this doesn't violate the laws of thermodynamics, but the headline makes it sound like this magics away the heat without using electricity or putting the heat anywhere.
Ye canna change the laws of physics, Captin.
Also Titanium is a bitch to extract if I recall correctly, hence the price. Still, options are good.
Ye canna change the laws of physics, Captin.
No, but you can write a bullshit article that has very little bearing on reality.
Goes quadruple for its title.
Agreed. But you can cool without heating the planet. It doesn't violate the laws of thermodynamics because it just uses a larger system - I.e. nocturnal radiative cooling.
No it said it does it without refrigerant.
The headline reads "A new cooling technology freezes food without warming the climate". It doesnt mention the lack of (gaseous) refrigerent.
The thing about machines that make them bad for the environment in general is the fact that they use up energy, which is nowadays still mostly created in a process that also releases massive amounts of CO2.
Its unlikely that the environmental impact of the gaseous refrigerent is as big as the impact of the CO2 that is created to run the fridge over its lifetime. It makes sense then to assume this fridge doesnt use power, since right now thats the only way it could cool without heating up the planet.
Im not saying this tech isnt interesting, but the headline is total BS
Old school refrigerants were absolutely horrendous ghg even modern ones are pretty bad with R134 being 1430x worse of a ghg than CO2
If we can reduce that, that’s good! And metals like titanium are recyclable so yes initially extracting them is bad but the full lifecycle isn’t as terrible
Modern refrigerants don't use R134
https://www.freon.com/en/industries/refrigeration/residential-refrigeration
R134 was the “safe” refrigerant to replace R-12 because R12 is 11000x more potent of a ghg than co2
There are some new refrigeration units that use R600 but the vast majority of refrigerators are still R134
R600 being a highly flammable gas (it’s butane) has slowed its rollout a lot. Hence why a solid state non volatile refrigerant is still a cool development
It doesn't use refrigerant, which is full of HFCs, HCFCs and CFCs.
In this case they just mean its not contributing to the greenhouse gases in the atmosphere.
But it is possible to do cooling without heating the earths atmosphere, if you manage to yeet the heat into space somehow, e.g. Paint that reflects the heat as light that passes through the atmosphere into space: https://youtu.be/KDRnEm-B3AI
I did watch a real good set of videos by Tech Ingredients, the chap's gotta be either a lecturer (and) or his special interest is DIY-ing everything from pulse detonation rocket engines (that turned out better than the ones ol muskrat's using) to using an underground heatsink made of plastic tubing and carbon saturated cement outside his workshop for an in-window AC unit, turning an 800W drain down to a 300W drain for the same cooling.
He was using some kind of fine particle paint to create a large Infrared radiating surface that shed heat so well it got below ambient air temp because it was shedding IR directly up out into space
The only unfortunate limit is shielding it from catching any outside radiation and making sure all the IR actually leaves the system, he had to build a shade to protect it from trees and buildings which would have been effectively shining IR back into the system.
This video;
Jesus Christ, whoever wrote this "article" has no idea what they're talking about. The researchers achieved sub-zero temperatures with a solid refrigerant, which is impressive. It has however absolutely nothing to do with climate change, because the heat still has to go somewhere. And the point that gas refrigerants are horrible greenhouse gases is not generally true anymore. Most new systems use gases as refrigerants that have equal or less impact on the atmosphere than co2 if they're released into the atmosphere. And that only happens if the loop is damaged, under normal operation it should stay sealed.
Under normal operation, in a perfect system it will stay sealed. Problems come at end of life and in real world use. Seals aren't perfect, gas escapes slowly. Some seals are bad, a blast chiller at my work needs regassing every other year. People dump old fridges and freezers on the street and they get damaged.
It all gets out eventually.
Yes, but the amount of gas in an AC system is insignifcant compared to the CO2 generated just making the AC system in the first place. Hell, delivering it probably generated significantly more pollution. Not saying we shouldn't strive to make it better, but it's not as actively harmful as it was 30+ years ago.
amount of gas in an AC system is insignificant compared to the CO2 generated just making the AC system in the first place.
Let alone running the damn thing (on fossil fuel electricity).
That's thermodynamically impossible but ok.
When you cool something you take heat energy out of it you have to do something with that heat energy you can't just delete it.
Seriously this! I feel like that cobra chicken meme where I'm yelling
"where does the entropy go?"
"WHERE DOES THE ENTROPY GO‽"
You don’t overcome thermodynamics, but you can work around them. For example:
When you cool something you take heat energy out of it you have to do something with that heat energy you can't just delete it.
Or you can shunt it into space so that it doesn’t heat the atmosphere on its way out. That’s called radiative cooling and it’s brilliant.
And it can be done at home with household items. See Nighthawk’s YT channel for more info: https://youtu.be/N3bJnKmeNJY
And that’s just one out of many possible approaches. Interesting read: https://en.wikipedia.org/wiki/Reflective_surfaces_(climate_engineering)
That's reflection of external heat not removal of internal heat. Refrigeration requires effort and therefore energy.
Published on Nature. 40 € article.
Here's the news article from the university.
This advancement results from a synergistic combination of materials, heat transfer fluid and refrigeration structures.
Operating at 1Hz, the desktop-scale device achieved a cold-source temperature of -12 ℃ from a room-temperature heat sink (24℃), establishing a temperature lift of 36 ℃. This is the first reported sub-zero Celsius performance in elastocaloric cooling. In a real-world demonstration, the system was integrated into a package measuring 1.0×0.5×0.5m3 and tested outdoors at temperature between 20 and 25℃. It successfully cooled an insulated chamber down to a stable -4℃ air temperature within 60 minutes and froze 20ml of distilled water into ice within 2 hours, validating its real-world freezing capability.
no power efficiency metrics? iirc one of the bigger issues of elastocalorics was the power efficiency
Elastocaloric coolers are not new. There are even some versions that you can buy right now, they usually for niche industrial use and have their own set of problems, namely that they're not remotely as efficient as vapor compression so it costs more and moves less heat.
The breakthrough here was discovering a different alloy that allows sub-zero temperatures. It doesn't change the efficiency which is the primary barrier to adoption.
But past cooling devices have not had enough cooling power for commercial use. The HKUST team developed a device that uses a new type of solid refrigerant, a nickel-titanium alloy with a higher nickel ratio. They also use calcium chloride as the working fluid that transfers heat away for cooling. Their design connects multiple alloy tubes together for a cascading effect that amplifies cooling.
In outdoor tests, the desktop device cools a surface down from 24°C to -12°C, and froze water in two hours. Sun Qingping, the mechanical and aerospace engineering professor who led the work, said in a press release that the researchers plan to increase the system’s efficiency and make it more cost-effectiveness by using advanced shape memory alloy materials and trying different system designs.
Cool.
Er, so to speak.
Cool, but I'm always a bit dubious by these statements.
Refrigerating just 12% of the produce that goes to waste every year due to spoilage would feed an estimated 1 billion more people.
I mean, I know cooling is important and making the process more efficient will make things better. But the reason why most of that food is thrown away is not lack of refrigeration, cheaper refrigeration will not solve that problem.
cheaper refrigeration would DEFINITELY help this problem. the big issue with food waste is food spoils so quickly (especially produce and meat), so it makes more sense to toss it than try to find a big enough space that's REFRIGERATED because the food is usually free, no one wants to spend thousands preserving it. cheaper refrigeration would absolutely improve this scenario.
Refrigeration already is cheap. The problem a lot of places have is not an inability to afford a refrigerator it's no energy to power the refrigerator. This technology does not into address that problem. In fact it probably worsens it because this technology is less efficient in terms of power consumption.
Also I would love to live in the world where you live because over here food costs money. It isn't free.
But the reason why most of that food is thrown away is not lack of refrigeration, cheaper refrigeration will not solve that problem.
I think "cheaper refrigerators" is an oversimplification. People without access to a functional refrigerator often have bigger problems than a mere absence of a single appliance.
But the energy savings is a big deal. We're not just talking about food refrigeration but AC, which is a much bigger deal especially as we suffer a warning planet
Exactly
The link says 'zero-emissions-cooling'
The article sez: "It relies on the temperature change of materials called shape memory alloys (SMAs) when they are stretched and released."
How do you stretch something without producing any emissions?
You can't. It's a different kind of heat pump.
If it is more efficient than vacuum-compression it's good.
Most refrigerants are extremely toxic and extreme green house gasses. But there are safer alternatives, eg. CO2.
I don't think shape change materials are all that efficient. The problem being is you still need some mechanism to compress the material again, which obviously uses energy. As you say their main advantage is that they don't use traditional refrigerants. But the trade-off for that is that they are mechanically more complicated and probably for any given amount of cooling will require more electricity.
You can trade those off with renewable energy sources of course so it may still be worth it but technically they are worse efficiency than traditional vacuum pumps.
I thought the same thing.
Seems they are mainly saying they developed cooling method that doesn't rely on a greenhouse gas for a refrigerant. Not nothing.
...and if you stretch and release something off solar/wind power greenhouse emissions will be very low indeed.
I'm curious about lifespan of these systems. I don't know much about SMAs, but my intuition says they degrade. Am I wrong? I hope I am :)
Oh geeze, it's that rubber band refrigerator that (I think) Tech Connections demoed?
Coefficient of performance (i.e. energy efficiency) at decent delta-T is always the most important factor and rarely mentioned.
Modern cooling equipment generally has the largest environmental impact from energy consumption, not manufacturing or refrigerant leakage.
Especially with ultra-low-GWP propane or butane refrigerant, though that's not usually used in large-scale systems.
This made me wonder how much heat/emissions are generated creating liquid nitrogen. 🤔
You just compress the gas to make it liquid, right? But then, I guess you'd need to provide pure nitrogen and I'm not sure what the main source of that is other than the atmosphere itself. How do you separate it?
How do you separate it?
Fractional distillation of liquid air I believe (like separating petrol and diesel).
I'm sure it's more complex than I'm making it out to be, but each gas in the air has its own freezing/melting boiling/condensation/sublimation points, so I'd imagine you could just kind of take advantage of that
Basically just cool it down to x temperature at y pressure, and all of the carbon dioxide should be solid, the oxygen a liquid and the nitrogen still a gas, and they've all sort of separated themselves out. Fish out the dry ice, siphon off the oxygen, and you're left with nitrogen.
Might need to do a couple more rounds of that on each of those to account for other gases in the mix depending on how pure you need it to be, but in theory I imagine it could be that simple (again in practice I'm sure there's probably a lot of details I'm missing)
Maybe cool the planet with it.
easy, just cause 1 or more supervolcanoes to erupt. or a large asteroid throwing dust into the air.
So multiple, nickel-titanium alloy tubes, are stretched and released within the refrigerator, causing a temperature change in the alloy, the heat of which (pulled from the interior) transferred to the calcium chloride fluid, being pumped around through the tubes; to be transferred to the outdoor climate, by use of an exterior heat exchanger. Something along those lines?
Cool.
