• Advertisement

Powerless fridge

Post general Oregon topics here

Powerless fridge

Postby Conook » Sat Jun 08, 2013 12:18 am

Anyone build a powerless fridge? I read an article about building one. Basically it consists of a chamber surrounded by wool or sawdust that is sandwiched against the inner chamber by another wall. Then you add water to the wool or other medium and that's it. Apparently evaporation is the cause of the cooling. The inner core temp is claimed to be a stable 40 degrees F.

I want to hear what your thoughts are. I may try to make one just to test it out. If it works that would be interesting.

Never forget that only dead fish swim with the stream.
Malcolm Muggeridge
Posts: 14
Joined: Fri Sep 07, 2012 8:29 pm
Location: Grants Pass, Oregon
Karma: 0

Re: Powerless fridge

Postby gracebowen » Sat Jun 08, 2013 12:45 am

sounds intriguing. I would like to know how it turns out if you make one.
Posts: 196
Joined: Tue Jan 01, 2013 1:50 am
Karma: 9

Re: Powerless fridge

Postby Conook » Sat Jun 08, 2013 1:08 am

Ok I did some research elsewhere and found a good site with a temp chart. Says 40 isn't quite the achievable goal. Still can bring temps down. A very good article. I am still going to try to make one just for fun. Experience is key in prepping and it might be a good idea to put hat info in my head with a practical build.

Hope the link is informative enough

http://rebuildingcivilization.com/conte ... lectricity
Never forget that only dead fish swim with the stream.
Malcolm Muggeridge
Posts: 14
Joined: Fri Sep 07, 2012 8:29 pm
Location: Grants Pass, Oregon
Karma: 0

Re: Powerless fridge

Postby kappydell » Sat Jun 08, 2013 3:39 am

Ive built several. They are easy to make with expedient materials, but obviously are better if done permanently. On a 90 degree day the inside of the small one I made (very small, commonly called a 'butter keeper'...) was 70 degrees. In the shade it would have been cooler.
Their effectiveness depends on the air humidity and air movement, since they work by evaporation. Look up Coolgardie safe on Wickipedia...if you put in Evaoration coolers you will get a lot of sites trying to sell swamp coolers, which are NOT the same thing.

Coolgardie was the site of a gold rush in the early 1890s, prior to the Kalgoorlie-Boulder gold rush.
For the prospectors who had rushed here to find their fortune, one challenge was to extend the life of their perishable foods — hence the invention of the Coolgardie safe.
The safe was invented in the late 1890s by Arthur Patrick McCormick, who used the same principle as explorers and travelers in the Outback used to cool their canvas water bags: when the canvas bag is wet the fibers expand and it holds water. Some water seeps out and evaporates, especially if it is in a breeze, cooling the stored water.
This technology is commonly thought to have been adopted by explorer and scientist Sir Thomas Livingstone Mitchell, who had observed the way some Aborigines used kangaroo skins to carry water.
The Coolgardie Safe was made of wire mesh, hessian (canvas), a wooden frame and had a galvanised iron tray on top. The galvanised iron tray was filled with water. The hessian bag was hung over the side with one of the ends in the tray to soak up the water.

Gradually the hessian bag would get wet. When a breeze came it would go through the wet bag and evaporate the water. This would cool the air inside the safe, and in turn cool the food stored in the safe. This cooling is due to the water in the hessian needing energy to change state and evaporate. This energy is taken from the interior of the safe (metal mesh), thus making the interior cooler. There is a metal tray below the safe to catch excess water from the hessian.

It was usually placed on a veranda where there was a breeze. The Coolgardie safe was a common household item in Australia until the mid-twentieth century. Safes could be purchased ready-made or easily constructed at home. Some of the metal panel safes are highly decorated, showing the creativity of their makers.
In the early 20th century, Coolgardie Safes were also manufactured commercially. These safes incorporated shelving and a door, had metal or wooden frames and hessian bodies. The feet of the safe were usually placed in a tray of water to keep ants away.

They don't get things really cold, but will keep milk from spoiling in the heat a while longer than without. The butter keeper will keep it from melting, but it won't really get hard. I don't know how to post a pic, or I would...I did find some super-simplified directions for the handy-person to try...

How To Build a Coolgardie Safe

There is no one true way to build a Coolgardie Safe. The following instructions were adapted from the Power House Museum's "Race Across Time" activity sheet, and is only meant to act as a guide. Due to its simplistic design, there are plenty of opportunities for you to use your own technical and creative skills when building a coolgardie safe.

1. Build a wood frame: a rectangular prism on legs about 30cm off the ground.

2. Add hinges to one side of the frame to make a door. Attach a clasp to keep the door shut.

3. Use solid wood for both the top and bottom to the wood frame.

4. Build a shelf out of strips of wood to fit inside the frame.

5. Attach hessian or other weave natural fabric to the frame on all four sides. (Hessian is Brit-speak for canvas)

6. Place on top a tray that takes up most of the area, or several smaller trays that fit along each side. The trays should be able to hold no less than 5cm of water.

7. Place a strip of hessian on each side of the safe so that one end of the strip is in the tray and one end near the bottom of the frame. Make sure all the material sides and strips are wet.

8. Place the safe in a shaded breeze spot.

9. Stand the legs in tins of water - this will help keep ants from getting inside the safe.

10. Place a food item on the shelf inside the safe and close the door.
New laws are like new taxes....both evolve, but they never go away.
Wisconsin Preppers Network
Wisconsin Preppers Network
Posts: 1458
Joined: Tue Dec 27, 2011 12:15 pm
Location: south central Wisconsin
Karma: 66

Re: Powerless fridge

Postby arkieready » Sat Jun 08, 2013 7:28 am

Same principle as a zeer pot, used in Africa. A large clay pot inside a larger clay pot, maybe 1-2" larger all around, with the space between packed with damp sand. The top is covered with a damp towel. keeps veggies fresher for market - less wilting. Same evaporative effect. No, they do chill as cool as some claim, but cooler is better than nothing. Humidity will hamper the effect. Desert climes would work best. Heck, we can see it in use now! Ever see a guy with his beer or pop in a paper bag? The paper absorbs condensation from the cold can, in turn evaporating and keeping it cool longer. One of my canteens has cotton side coverings I could wet down.
I read about the zeer pot years ago and logged the info away in my brain for "someday". I would use it. I plan to research the coolgardie, too. "cool" stuff, eh?

Happiness makes up in height for what it lacks in length.

--Robert Frost--
Arkansas Preppers Network
Arkansas Preppers Network
Posts: 3356
Images: 0
Joined: Mon Aug 08, 2011 10:08 am
Karma: 93

Re: Powerless fridge

Postby kr105 » Sat Jun 08, 2013 7:36 am

There are several threads on this and a whole section on the main forum, that discusses this (if you are interested.). Here is a link: viewtopic.php?f=343&t=14436&p=127145&hilit=zeer#p127145

'Hope it helps.
Pennsylvania State Moderator
Pennsylvania State Moderator
Posts: 2707
Joined: Wed Jun 30, 2010 12:48 pm
Karma: 95

Re: Powerless fridge

Postby Conook » Wed Jun 12, 2013 12:14 am

Nice info kappydell. Love the history lesson as well. I think I am going to make one. I will post my findings if I can figure it out. Thanks everyone for the info.
Never forget that only dead fish swim with the stream.
Malcolm Muggeridge
Posts: 14
Joined: Fri Sep 07, 2012 8:29 pm
Location: Grants Pass, Oregon
Karma: 0

Re: Powerless fridge

Postby newbieprep » Thu Jun 13, 2013 3:50 pm

I would be really interested in a pic and more details if you complete this project!
The greatest fear in the world is of the opinions of others. And the moment you are unafraid of the crowd you are no longer a sheep, you become a lion. A great roar arises in your heart; the roar of freedom. ~ Osho
Iowa Preppers Network
Iowa Preppers Network
Posts: 152
Joined: Mon Jun 03, 2013 11:08 am
Location: Eastern Iowa
Karma: 6

Re: Powerless fridge

Postby retired prepper » Thu Jun 13, 2013 9:39 pm

Learning to build an old time ice house for you or your community might be a good idea. I saw one at an old history farm/museum. If you live near a lake or river, getting a crew to cut ice blocks is a great community project. I am talking in a long term SHTF /emp situation. Must be some instruction out there, it was a simple structure, lot of sawdust and hay I remember.
retired prepper
Posts: 282
Joined: Sun Nov 18, 2012 9:12 pm
Karma: 18

Re: Powerless fridge

Postby namwal » Thu Jun 13, 2013 9:46 pm

Like swamp coolers, don't think they would work in extremely humid climates. My fridge in my camper while using propane and a battery, is free of electrical grid power...
"World oil production can probably keep going up for another 6 or 8 years. But some time in the 1980s it can’t go up much more. Demand will overtake production."-jimmy carter 1977

"Because of increased dust, cloud cover and water vapor the planet will cool, the water vapor will fall and freeze, and a new Ice Age will be born"-Newsweek 1970

"civilization will end within 15 or 30 years unless immediate action is taken against problems facing mankind,”-George Wald 1970.
User avatar
Texas Preppers Network
Texas Preppers Network
Posts: 2124
Joined: Thu Sep 29, 2011 10:47 pm
Location: Texas
Karma: 142

Return to Oregon Discussion, News and Weather

Who is online

Users browsing this forum: No registered users and 1 guest

Email Newsletter icon, E-mail Newsletter icon, Email List icon, E-mail List icon Sign up for the APN Email Newsletter - Enter your e-mail address below

  Links and Resources
  -Free Ebooks

Trusted Sponsors

For Notices of Copyright infringement and to contact our DMCA Agent please follow the link below:
Copyright Policy

For terms of use, rules, and policies please read our Disclaimer