Passive refigeration

In the Dec/Jan issue of MIT Technology review there is a short piece about a refigeration device that needs no electricity. (I know, gas refigerators. but this device is much simpler). The device is a cylander 10cm by 20cm with a handle. It is described as two chambers, one steel, one aluminum, separated by an insulating ceramic disk fitted with two valves. In use, the device's steel end is placed in a fire for 30 minutes. A refigerant is boiled and moves as a gas to the second chamber via a one way valve. The unit is then allowed to rest to allow the gas to condense (doesn't say how long). Then the device is inverted and the aluminum end is inserted into a food storage pot. I cools by absorbing heat and moving the gas back to the first chamber vie a valve that opens when the unit is inverted.
It claims that it can keep a 32 liter food storage pot cooled to 4 deg C for 24 hours.
Now, I know that this is not a very good description of the device, a few details of it's opperation are missing. For instance, I assume that a vacuume is developed in the steel end of the device once it is allowed to cool. And that that vacuum lowers the boiling point of the refrigerant in the other chamber. Other wise why would inverting the device and opening a valve cause it to cool? Also how is the refrigerant moved to the second chamber while on the fire? Is it simply moved as a gas and condenses in the second chamber? Wouldn't a tube to move the refrigerent (somthing like a coffee perculator)be more efficient?
Anyone want to try to reverse engineer this and make one of your own?? Might be an intresting way to get cooling from excessive solar hot water or Generator exhust.

Functionally this sounds like the old "IcyBall" that Crosley made back in the 1930s (google IcyBall for more info), just updated with modern materials. I'll be looking for more info in the future, maybe can replace my old Icy Ball unit with something more efficient.

Gordon reeder wrote:

In the Dec/Jan issue of MIT Technology review there is a short piece about a refigeration device that needs no electricity. (I know, gas refigerators. but this device is much simpler).

What you describe sounds like what I understand my propane "absorption" refrigerator to be doing - with a tedious manual intervention. Doesn't sound simpler to me :-) Absorption refrigerators are pretty simple - all they need is a heat source - what the source is doesn't matter.

Anyone want to try to reverse engineer this and make one of your own?? Might be an intresting way to get cooling from excessive solar hot water or Generator exhust.

I could probably connect mine up to a solar hot water supply, too (though I don't know if that's hot enough). -- derek

"WisJim" wrote in message

Functionally this sounds like the old "IcyBall" that Crosley made back in the 1930s (google IcyBall for more info), just updated with modern materials. I'll be looking for more info in the future, maybe can replace my old Icy Ball unit with something more efficient.

Sure can..try an Amonnia frig. Just light a little fire underneath.

"Gordon reeder" wrote in message

Now, I know that this is not a very good description of the device, a few details of it's opperation are missing. For instance, I assume that a vacuume is developed in the steel end of the device once it is allowed to cool. And that that vacuum lowers the boiling point of the refrigerant in the other chamber. Other wise why would inverting the device and opening a valve cause it to cool?

I'll try to make it as simple as I can. It's basic high school physics really.
When a vapor is compressed into a liquid, a good deal of heat is given off. When the pressure is released and the liquid is allowed to evaporate into a vapor again, it "wants it's heat back," so it feels very cold as it absorbs this heat.
Putting the steel end in the fire, merely boils the liquid out of that side of the chamber, through the one-way valve and it collects in the aluminium side under pressure. The aluminium side would remain quite warm until room temperature cooled it down, and in this process, the refrigerant in the chamber would condense to liquid.
When this room-temperature apparatus is turned over, the pressure on the liquid is released, and it starts to boil, turning back to vapor. As stated before, when liquid turns back to vapor, it absorbs heat, and feels cold. This is similar to an aerosol can of deodorant, which contains a liquid as a propellant, which boils when you press the nozzle, and feels quite cold when it hits your skin.

Also how is the refrigerant moved to the second chamber while on the fire? Is it simply moved as a gas and condenses in the second chamber? Wouldn't a tube to move the refrigerent (somthing like a coffee perculator)be more efficient?

The heat merely boils the liquid, creates more pressure in the chamber, and it drives most of the liquid to the other, cooler side through a tube which draws from the bottom of the reservoir.

Anyone want to try to reverse engineer this and make one of your own?? Might be an intresting way to get cooling from excessive solar hot water or Generator exhust.

It could probably be done, but it would be difficult to make it efficient and cost-effective without a lot of careful engineering. Another problem might be finding a refrigerant which is efficient, legal and safe.

"WisJim" wrote in news:1135731185.654900.34420 @g44g2000cwa.googlegroups.com:

Functionally this sounds like the old "IcyBall" that Crosley made back in the 1930s (google IcyBall for more info), just updated with modern materials. I'll be looking for more info in the future, maybe can replace my old Icy Ball unit with something more efficient.

Well, well. I learned somthing new today. Thanks for the tip. Looks like it works very much like the Icyball. Seems to be improved by combining the hot and cold balls into a single cylinrical unit and there is that valve that keeps the cool process from starting untill it is inverted. I assume that the Icyball is removed from the chest for recharging.

"JoeSP" wrote in message

"Gordon reeder" wrote in message
Now, I know that this is not a very good description of the device, a few details of it's opperation are missing. For instance, I assume that a vacuume is developed in the steel end of the device once it is allowed to cool. And that that vacuum lowers the boiling point of the refrigerant in the other chamber. Other wise why would inverting the device and opening a valve cause it to cool?
I'll try to make it as simple as I can. It's basic high school physics really.
When a vapor is compressed into a liquid, a good deal of heat is given off. When the pressure is released and the liquid is allowed to evaporate into a vapor again, it "wants it's heat back," so it feels very cold as it absorbs this heat.
Putting the steel end in the fire, merely boils the liquid out of that side of the chamber, through the one-way valve and it collects in the aluminium side under pressure. The aluminium side would remain quite warm until room temperature cooled it down, and in this process, the refrigerant in the chamber would condense to liquid.
When this room-temperature apparatus is turned over, the pressure on the liquid is released, and it starts to boil, turning back to vapor. As stated before, when liquid turns back to vapor, it absorbs heat, and feels cold. This is similar to an aerosol can of deodorant, which contains a liquid as a propellant, which boils when you press the nozzle, and feels quite cold when it hits your skin.
Also how is the refrigerant moved to the second chamber while on the fire? Is it simply moved as a gas and condenses in the second chamber? Wouldn't a tube to move the refrigerent (somthing like a coffee perculator)be more efficient?
The heat merely boils the liquid, creates more pressure in the chamber, and it drives most of the liquid to the other, cooler side through a tube which draws from the bottom of the reservoir.
Anyone want to try to reverse engineer this and make one of your own?? Might be an intresting way to get cooling from excessive solar hot water or Generator exhust.
It could probably be done, but it would be difficult to make it efficient and cost-effective without a lot of careful engineering. Another problem might be finding a refrigerant which is efficient, legal and safe.

The cost of heating has to be considered also.

Derek Broughton wrote:

Gordon reeder wrote:
In the Dec/Jan issue of MIT Technology review there is a short piece about a refigeration device that needs no electricity. (I know, gas refigerators. but this device is much simpler).
What you describe sounds like what I understand my propane "absorption" refrigerator to be doing - with a tedious manual intervention. Doesn't sound simpler to me :-) Absorption refrigerators are pretty simple - all they need is a heat source - what the source is doesn't matter.
Anyone want to try to reverse engineer this and make one of your own?? Might be an intresting way to get cooling from excessive solar hot water or Generator exhust.
I could probably connect mine up to a solar hot water supply, too (though I don't know if that's hot enough). -- derek

Sounds like a handy device for a camping or post disaster type living environment. For a fixed location, i.e., with generators and so on, an ammonia cycle fridge would probably be more appropriate. Of course, getting the generator exhaust heat to the fridge hot point in a safe fashion may be more hassle than it's worth. Perhaps if you keep a second fridge out next to generator?
--Dale

JoeSP wrote:

It could probably be done, but it would be difficult to make it efficient and cost-effective without a lot of careful engineering. Another problem might be finding a refrigerant which is efficient, legal and safe.

Take 2 propane bottles and connect via high pressure pipe. Done.
NT

wrote in message

JoeSP wrote:
It could probably be done, but it would be difficult to make it efficient and cost-effective without a lot of careful engineering. Another problem might be finding a refrigerant which is efficient, legal and safe.
Take 2 propane bottles and connect via high pressure pipe. Done.
NT

wrote in message

JoeSP wrote:
It could probably be done, but it would be difficult to make it efficient and cost-effective without a lot of careful engineering. Another problem might be finding a refrigerant which is efficient, legal and safe.
Take 2 propane bottles and connect via high pressure pipe. Done.
NT

Right, so...
Put one bottle in a fire, wait how long? then what?

meow2222@care2.com wrote:

JoeSP wrote:
It could probably be done, but it would be difficult to make it efficient and cost-effective without a lot of careful engineering. Another problem might be finding a refrigerant which is efficient, legal and safe.
Take 2 propane bottles and connect via high pressure pipe. Done.
NT

Would only work if one tank was very much larger then the other one. At the start the small tank would be full of liquid propane, and the large tank be at a vacuum. The large tank would have to be big enough to hold all that propane as a gas at a low enough pressure that the last bit of liquid propane will still boil at some usefully low temp. _________ Andre' B.

andre_54005@yahoo.com wrote:

meow2222@care2.com wrote: JoeSP wrote:
It could probably be done, but it would be difficult to make it efficient and cost-effective without a lot of careful engineering. Another problem might be finding a refrigerant which is efficient, legal and safe.
Take 2 propane bottles and connect via high pressure pipe. Done.
NT
Would only work if one tank was very much larger then the other one. At the start the small tank would be full of liquid propane, and the large tank be at a vacuum. The large tank would have to be big enough to hold all that propane as a gas at a low enough pressure that the last bit of liquid propane will still boil at some usefully low temp. _________ Andre' B.

The bottles are the same size, and neither is anywhere near full, just as a fridge's circuit would not be filled to the brim with liquid refrigerant either.
The bottles should be mounted on a strip of metal/wood etc, and thin metal pipe used to connect them.
NT

Here are sites that shows home built 'IcyBall" type units. I know that there are some other websites showing homebuilt ones too. http://www.fridge.lionheart.net/ http://www.ggw.org/~cac/IcyBall/HomeBuilt/HallPlans/IB_Directions.html http://www.ggw.org/~cac/IcyBall/HomeBuilt/HomeBuilt.html Maybe this will help folks understand them. This getting me interested in getting mine working again--I just have the cooling unit, no cabinet etc.
Jim

"WisJim" wrote in message

Here are sites that shows home built 'IcyBall" type units. I know that there are some other websites showing homebuilt ones too. http://www.fridge.lionheart.net/ http://www.ggw.org/~cac/IcyBall/HomeBuilt/HallPlans/IB_Directions.html http://www.ggw.org/~cac/IcyBall/HomeBuilt/HomeBuilt.html Maybe this will help folks understand them. This getting me interested in getting mine working again--I just have the cooling unit, no cabinet etc.
Jim

Interesting ideas. I have been looking at the Robur gas fired stuff. They have a basic 5 ton package unit. Unfittingly the heating is poor for my application.