alt Hacker NewsThe Einstein-Szilard Refrigerator (2020)
Comments
My parents had a completely noiseless refrigerator similar to this. It did not have a compressor and had an electric heating element instead. It was very durable and worked for many decades until the plastic and door hinges etc was too damaged for it to be used any more.
I actually found a picture of the exact model from a museum
https://digitaltmuseum.no/011014769284/evalet-kjoleskap/
I looked at bit more and it seems the original article is quite misleading. It seems the Einstein-Szilard refrigerator is a type of absorption fridge and a major reason they did not come to market was a related absorption fridge, the Platen-Munters absorption refrigerator made by Electrolux and Evalet. The Einstein-Szilard refrigerator was not completely unique, but an attempt at improving this design with other gases.
Since I haven't seen anyone bring up the viability of this method yet, here are a few additional bits of info I dug up:
> the total mass of the completed apparatus is around 400 kg with 20 kg of alcohol in the refrigeration cycle
> The group, led by Malcolm McCulloch noted that the design was still "nowhere near commercialised", but might allow the efficiency of the original Einstein–Szilárd design to be quadrupled.
It would be great if someone could improve this tech to where there's a breakeven point of ownership (preferably less than 20 years) when it becomes a better deal than other modern refrigerators.
Szilard is an underrated genius. Also was an early formulator of the nuclear chain reaction concept, to tap into nuclear energy, but did not zero in uranium right at the outset as the element to make it feasible.
This is the fridge that is used in the book and movie 'The Mosquito Coast'.
"It isn’t possible to know what Einstein and Szilard might have accomplished, had their professional and personal lives not been interrupted."
Is it just me?
On a related note, there is a reasonably well known commentary on an adjacent technology by Ruth Schwartz Cowan (1985) titled "How The Refrigerator Got Its Hum". It describes a 1930s market battle between heat-driven ad/absorption chiller technology ("Kelvinator") and work-driven compressor chiller technology ("GE"). Tl;DR GE won.
The ab-chiller is likely best known these days as the "propane fridge" in RVs.
Sadly, the only online resources for Cowan's work I can find are either Scribd paywalled [1], the entire book in which Cowan's piece is a chapter on the Internet Archive [2] or a pointer-to-a-pointer from a piece in the Guardian [3] to a boingboing piece [4] that seems to be offline.
(Background: I work in Direct-Use geothermal. Such ad/absorption chillers are one major tool in the toolbox for low-T cases where it is uneconomical to turn geothermal heat into electrical energy -- mostly due to Carnot's Law considerations.)
[1] https://www.scribd.com/document/527479452/Cowan-How-the-refr...
[2] https://archive.org/details/socialshapingoft0000unse_g5b0
[3] https://www.theguardian.com/science/political-science/2014/f...
[4] https://boingboing.net/2012/08/20/how-the-refrigerator-got-i...
I linked to this same article a few years ago, although the original URL is now broken.
History can be so weird (and funny).
Was there also an Oppenheimer-Bohr outdoor grill?
I believe these types of refrigerators are used on RVs and camper vans
> Einstein and Szilard eliminated the risk of leakage by jettisoning the mechanical pump
Einstein–Szilard refrigerator: https://en.wikipedia.org/wiki/Einstein_refrigerator :
> The three working fluids in this design are water, ammonia, and butane. [1] The Einstein refrigerator (co-invented with Leó Szilárd) was actually a modification of an earlier three-fluid absorption design created by Swedish engineers Baltzar von Platen and Carl Munters
Hmm. Would a refrigerator built like this be silent?
These sort of refrigerators are common in RVs and campers as they usually have a propane tank, as well as commercial/industrial installations that have waste heat and cooling needs (absorption chillers).
Now imagine now this being used in a liquid-cooled computer with no moving parts. Any takers?
a great book or documentary idea would be a different angle on Einstein regarding all his amazing partnerships
I found his partnership with Satyendra Nath Bose one of the most fascinating, when Bose couldn't get his paper published Einstein took it upon himself personally to translate it and get it published for him
(Bose was BRILLIANT, he discovered the Boson particles by mathematical statistics!
https://en.wikipedia.org/wiki/Satyendra_Nath_Bose#Bose%E2%80... )
(2020)
[dead]
It's a very clever trick: a refrigerator without a compressor which uses heat as the energy source. It could run on either a gas flame or an electric heating element.
There are three working fluids (butane, water and ammonia) and it works by exploiting differences in partial pressure (that is, the pressure contributed by each component of a gas mixture). Instead of using a compressor to change the overall pressure, it changes the composition of the mixture.
The cycle basically works by adding and removing ammonia at different points to make the butane refrigerant evaporate and condense in the appropriate places.
On the "condenser" side of things, water is used to remove the ammonia from the gas mixture by absorption. Because the total pressure is approximately the same throughout the system, removing ammonia increases the butane mole fraction and therefore its partial pressure, causing the butane to condense. This is the heat rejection side.
On the evaporator side, ammonia is added again. This lowers the butane partial pressure, shifting the equilibrium and causing the liquid butane to evaporate. That's where the cooling effect occurs.
The other part of the cycle is regenerating the ammonia by separating it from the water again. That's where heat is added, and that heat input is what ultimately drives the process.