Using a Zeer Pot instead of a Refrigerator

I was reading a woman's dream about become self-sufficient, and she mentioned using a Zeer Pot. Of course, I thought, "what the hairy heck?" but they did a little internet surfing.

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The pot-in-pot refrigerator, also known as a Zeer الزير in Arabic, is a refrigeration device which keeps food cool without electricity by using evaporative cooling.

It is constructed by placing a clay pot within a larger clay pot with wet sand in between and a wet cloth on top. As the water evaporates it cools, allowing food stored in the inner pot to be kept fresh for much longer in a hot, dry climate. It must be placed in a dry, ventilated space for the water to evaporate effectively towards the outside.

Mohammed Bah Abba invented the device in 1995 and was awarded a Rolex Laureate (Rolex Awards for Enterprise) in 2000 for developing this “pot-in-pot preservation/cooling system”.

Of all the households in the US, 99.5% have refrigerators. About the same percentage have some way of heating food. We've seen some great gadgets for keeping things hot and cold here on Slashfood, but I want to show you an ancient technique for keeping food cool. It's called a zeer pot. The vessel itself may be third world, but it's playing a timely role in the continuing recovery of northern Darfur and other African nations. Science in Africa magazine states that a zeer can keep tomatoes edible for 20 days, as opposed to two, and meat two weeks, as opposed to a few hours.

A zeer pot is quite simple. It's basically two large earthen pots, one nested in the other. The space is filled with sand and water is added. A damp cloth covers the top. As the water evaporates, the inner pot containing the perishables is kept cool in the same manner that a mechanical refrigerator operates -- water evaporation draws heat from the inner vessel. Water is added twice a day.

Muhammed Bah Abba is credited with reviving (some say inventing) use of the zeer and has his own instructions on theory, application and making one. I am going to make one of these myself and see how long basic vegetables will keep at room temp. You can see from the picture how easy it would be to improvise a zeer with regular flower pots. I will then give it a taste test after one week.
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We definitely want to reduce our carbon footprint, get off the grid, and eliminate using a refrigerator that could break down. I've seen lots of old-timey-type boxes and ice-boxes, but like this idea. When you have all of your food right at your fingertips for harvesting, and a cow in the barn for making fresh butter, you really don't need a LOT of refrigerator space. This sounds wonderful.

I couldn't find any retailers online for these. Questions:

  • will any clay pot in a clay pot work this way?
  • will any kind of sand work in the bottom pot?
  • just a wet cloth on top? does that keep much coolness in? what if you can't re-wet the cloth twice a day?
  • as an alternate, what kind of top would you put on... and would it be on both or just the inner pot?



Kiki-Chan said...

I can not tell you from experience, since I live in puerto rico and the humidity is so high that this does not work. but I have seen some articles on the net and as far as I can remember the important thing is to get unglazed pots and coarse sand. and I think I have seen it with a terracotta lid

ThrtnWmsFam said...

Thanks. I wonder if it's possible to find square terra cotta pots (inner and outer) to fit several along a wall. We don't have a lot of humidity here in the Denver, Colorado area, so this should work for us if I can figure out the logistics. Vikki

RovingWeaver said...

I had been wondering about the lid, too. I just moved to northern OK, and need to figure out what the average humidity rate is here. Did you ever try yours? I really want to make one! I have a back addition on the house I'm renting that stays too hot - I'm thinking it would be perfect, if I vented it a bit. :-) The refrigerator in this house is fine, but I want to see if this works for when I have my own place again!

ThrtnWmsFam said...

No, I haven't had a chance to try this, but you can believe that I will when we get settled onto our homestead. Which, at the rate this is going, may be another year. Yeck.

Thanks for stopping by. Please come again! :) Vikki

MelVil said...

I would think that where a swamp cooler works this should work as they both work on the same evapritive principle.
swamp coolers don't work in humidity above about 20%