Frigeration without electricity--fuel

[Mullenite]

efrigeration without electricity or fuel

--------------------------------------------------------------------------------

Hello,
I was doing some research on more efficient refrigerators recently, since the fridge is one of the top five energy wasters in the home, and came upon something called a passive refrigerator. That's a fridge that doesn't need electricity or fuel to keep things cold.

Did you know that the ancient Egyptians had refrigerators and freezers? I'll let that one sink in for a second. Ancient Egypt, the desert, no electricity had sundaes? Here are some links.
Egyptian Refrigerator
Egyptians made ice
A .pdf explaining ancient refrigeration
Egyptian jars of ice
A Radiant Refrigerator
They used the powers of the heavens. You see, the night sky, specifically deep space has a constant temperature of just a few degrees above absolute zero. Absolute zero is the absence of all heat. Well, these Egyptians would make insulated boxes that they would point at the clear skies at night and the infinite void of the cosmos would gobble up all the heat inside the box. If they had water in the box then it would turn to ice. But they had to put an insulating lid on the box to prevent the heat of the day from trying to get into the box. This wouldn't work so well if they had clouds that night. But, Egypt is a desert, how often do they have clouds in the sky? The only other downside was you had to wake up before the crack of dawn to close the lid. And the ancient world wouldn't know of the alarm clock until the industrial revolution.

That ancient fridge isn't the only passive refrigerator around. The folks at Daystar: The Four Mile Island Icebox have a passive refrigerator that has been in operation for darn near 20 years! It uses a block of ice that is frozen in the winter and kept frozen for the rest of the year round. The down side to this fridge? You have to have freezing temperatures sometime in your location. Also it doesn't keep things frozen, only refrigerated.


And then there's the Crosley Icyball. It's a fridge that uses two metal spheres that are connected by a bent pipe, one filled with water the other with ammonia. Through the magic of chemical reaction one ball will freeze. That frozen metal ball is put into an insulated box (the fridge) and the other metal ball hangs outside. When the process is complete you have to recharge it by heating up a sphere. That can be done with fire or a solar cooker. Down side? There's some upkeep with this system. You have to maintain it daily or your food rots.

Upkeep is a down side that all these passive refrigerators share. I think that's a fair trade if you're trying to be self sufficient.

Any thoughts?

[WillowTheWhisp]

How about a solar powered fridge? That seems like it might be a good idea with little maintainance required.

[MorningStar]

Once when I went on a youth campout, we kept our cans of pop cold in the river. Worked great! I guess that's only handy if you have a river really close. :P