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I am interested in attempting to build a solar powered freezer where properly oriented Fresnel lens provided the power to run an ammonia cooled freezer. At this point, I don't see any reasons which in theory it should not work. With a properly insulated box, it looks to me what it would be powerful and practical.
Here's a link to a explanation of the process for those that are unfamiliar.
http://home.howstuffworks.com/framed.htm...ption.html
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I have had some thoughts along similar lines and might suggest you think in terms of building a "walk in" in lieu of concentrating on a small box. It not that hard to build a room to a higher insulation standard than a box freezer has and a cold room is so much more useful.
Assume the best and ask questions.
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I have seen old style propane ( hot point ) refrigerators around , just change the little flame for your solar set up
The devil is in the detail
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BTW, anhydrous ammonia will bite you if your not careful
The devil is in the detail
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Propane reefers and freezers work great, and with propane over $4.00 a gallon, this is a great idea to develop.
I know some folks at Miloli'i who use a propane freezer. They keep their day to day items like milk, cheese etc in a good ice chest. They use their freezer to make ice and store bulk food. That way the freezer is only opened once every day or two to switch out the ice jugs. This is much more efficient than a reefer that's opened and closed repeatedly all day long. (kids)
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Quite interesting. Hope you keep us posted on progress JW.
Rob, do you think ProTec would be a feasible material for a walkin?
David
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ProTEC is R-20 which I don't consider adequate but it could be doubled up. Rastra is R-30 which is closer to the mark.
Some of our metal faced SIP panels can be up to R-50. They come with food grade surfaces too.
I guess my point about a walk-in unit is that chest freezers are only marginally efficient and have minimal capacity. By the time you have your cooling system figured out it isn't much more expensive to do a larger unit with actual capacity. Hence - a walk-in unit.
I'm intending one on my farm on of these days.
Assume the best and ask questions.
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Properly done I might guess you could triple the capacity of those five units and run it with the equivalent of two of those units. If it's super insulated and not opened often it's way less expensive than buying a pile of G.E. products.
Assume the best and ask questions.
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