My daughter's grandmother lived back in the hills (in the 1950's) with no utilities. She had a screen box outside her kitchen window (shaded by the porch roof). It was wood frame, covered with metal screen on the sides, and that covered with burlap. She'd wet the burlap down, and as it dried it would lower the temperature. It was her 'cooler', year around.

My late father was in the British army in the 1950's stationed in the Middle East. They would wrap a water filled jerry can in a wet army blanket, keeping the blanket wet would cool the jerry can water down so much it would freeze! That's evaporative cooling for you!

stand the zeer pot on the little pots to get it in the air for more area exposed for more evap. put it in full shade & in slight breeze too for quicker evap. you will git better results.

I have a suggestion for you, place a foil sheet the shiney part facing outward over the wet towel this method should keep the contents inside the clay pot even cooler, try that. :-)

No impact man brought me here. This is crazy!!! How cool!!! A bit extreme for me but half I got a better explanation of what it is and how it works.

LOVE all your ideas--shows more thought goes into making something with as little to no cost, while incorporating design with function, and with uncompromised functionality.

Hi there! Good Idea old idea from the grand parent... We gonna try it soon is amazing thing to do!! Thank you for the video.

I love the little pots. Because, know body could ever tell the size of the big pots when you walked up to them. That's funny stuff.

i would think you could use very large pots and still get good cooling. the shape of the container shouldn't matter. square or rectangular pots should work fine too.

good questions. no, the pots have to be made from something pourous like clay (to allow for air flow).

you’re the coolest. my new fave page thank u so much

Really appreciate the idea ,I will apply it ...I have to wait a couple weeks before I buy a refrigerator , thank you 💕

Excellent experiment

It is most likely that what limits the cooling is the rate at which water can evaporate from the system. Addition additional insulation by additional pots or sand probably won't help much. If you could increase the surface area/volume ratio, you should get a greater cooling rate--so a smaller system might achieve a lower temperature. However you could fit less stuff in it (eg: your grapes example) and would need to re-wet it frequently as it can't hold as much water. The primary emergency use I can imagine for a zeer is to keep refrigerated medicines, especially insulin, cooled after a natural disaster until help arrives, or until evacuation becomes possible.

Appreciated the temperature statistics

You have to use a closed pot so the evaporating water cant get inside. Also, skip the sand. Water holds ALOT of thermal energy. The way you’re using the sand is basically the same as putting your pot in a bucket of water and setting it in the sun. It wont be hotter than the bucket of water, but the bucket of water is going to heat up because its going to absorb energy faster than it can evaporate. Ever hang out in a shallow pool in summer? Water gets pretty warm, but when you get out and there is a breeze you suddenly feel much cooler than when you were in all that water. Only water on the surface can evaporate and that’s where the cooling happens - all the water that’s in the sand cant evaporate till it gets to the surface; it’s like a pool of warn water. You want to keep the water on the surface. Take two pots of the same size; wax the inside surface. Turn one upside down like a lid to make a closed chamber with the two pots. Put the towel over closed pot and pour water over the towel, repeat a few times as the towel starts to dry out. I think you’ll have much better results with this method.

thank you for posting you are a blessing.

This reminds me of those 3-D printed houses that I was watching today because in those 3-D printed houses, the there is a gap in between parts of the 3-D print or I imagine you could pour sand into it and I assume use the same technique add water and it will keep the house insulated and cool like this pot in pot cooler.

Thanks so much for making this video about creating this brilliant Stone-Age :^) fridge. For starters I am definitely going to make 1 Stone-Age-pot-fridge. Here in Ireland electricity-prices are now Brutal. Old Age Pensioners with only a state pension, those who have storage heaters only, can't afford heating their homes. They pack sandwiches, thermos with tea, medicines, wrap up in warm clothes, use their free travel pass, get on a bus or train, travel aimlessly from A to ? and back home again, just to be warm. Heart breaking. That's the doing of the IMF Bankers-Gangsters who have Ireland too financially on her knees. Peace ...

This is awesome! Once again! Would it not be even more effective and efficient if it were buried also? Just a suggestion :)

Have you tried soaking the pot in water before assembling? Getting the pot to soak water before adding wet sand may improve performance.

Whoa, you living in hell or something? 122F???

I like the idea of cooling a couple of grapes, or a strawberry :D

Thanks for the video and testing with 3 pots. I'm wondering if there is a difference in performance depending on the sizes of the pots. I'm off the grid and really would like a place outside my fridge (which is really a freezer that runs several times a day) to store tomatoes and Armenian cukes. The tomatoes aren't supposed to get very cold anyway or they lose flavor, so this would be better than a fridge. How big could they be while still having good cooling? Do they have to be round?

Could you not fill copper capillary coils with nitrogen and have a closed system within the pot to keep things frozen or cold? Not to mention making a cold sink for home cooling needs?

The round pots are Better, completely wet the Clay pots prior, put sand around and leave in shade ideally. Could even be half inserted in the ground.

Shady spot too helps and I sink mine half way in the ground. In a breezy area. Make a video trying that please😁

This is called a zeer pot refrigerator btw.

could this be used as an air cooler? Maybe drill holes around the bottoms of both pots for pvc pipes tp get air flow in and an exhaust fan on top or an intake tube from the lid that almost reaches the bottom

I wonder how cool it can get if it's in the shade.

Does it matter what kind of sand it is? Like would fuji beach sand work just as good as the Sahara desert sand?

You should have made a lid that is the diameter of the most inner pot to cover the pot. And leave the surface area of the outer pots open so the water can evaporate, since it is suppose to be an evaporative cooler, to cool the inner pot and outer pot. And if you can line the lid with aluminum foil, it will keep the inner pot even cooler since the aluminum reflect the heat from outside from entering the inner chamber of the inner pot.

I'll try this with my house mate.

If I put a terracotta dish on top would that stay cool? I've seen some where you use the terracotta water catcher to cover the top. I was wondering if it would give feral cats a place to cool off a little bit if it's in the shade

How cool will the pots get when you set them in the shade instead of direct sunlight?

works for dry weather country.

Since they are powered by evaporative cooling, is the inner chamber cooler if the pot is in sun rather than in shade?

Would using vermiculite (from a garden center), be a better insulator? It would also absorb more water. It should be worth trying.

You need to pour more water, one liter is not enough, it will also help if you use cold water, or let ice cubes melt in the sand, the inner pot will be significantly colder, you can actually feel the frigid air inside the inner pot., if you put the wet towel and cover it with one of those pot bases that look like a plate it will stay even colder, and even more if you wet the pot base before putting it on top, it will help keep everything cold inside, try it and make a video about it.

Have you tried this with a liter of frozen bottled water as an "ice pack?"

I'll be making one to store fruits and fresh watter in my room (where I live is pretty hot and a small fridge just for me would be a total waste)

Good video man, 👍😊 put the thermometer in the shade out of direct sunlight... Evacuated thermal tube heaters can get up to 300+ degrees Celsius... Larger the light collector area, that hight the temp... Keep the thermometer in the shade so you can test the air temperature not the sun thermal infrared temp output, which can be very high 😳 Oh or can invest in a laser thermometer...

Nice sharing

I am an engineer. A domestic electric powered refrigerator cools down one enclosed space. Industrial cryogenic refrigerators that cool down several dozen degrees below zero are, as a bit of an simplification, a refrigerator in a refrigerator. In other words, one refrigerator cools down a refrigerated space to a temperature well below what the primary refrigerator can do. I wonder if a "pot in pot in pot in pot" system like this could cool it down more than 40 degrees. If the ambien temperature is 38 Celsius and you want to cool it down to 2 degree Celsius, could it be done?

A darker towel might be more effective because the white towel will be reflective; as a black towel should get hotter therefore evaporating at a quicker rate- but thats just a suggestion based on color science as black absorbs all wavelengths. Where as white reflects all wavelengths (except when it comes to paint that's a bit more complicated) Edit:typo

Other videos show this zeer pot off the ground for ventilation. That could cool it off more, as well.

I hope to experiment with this idea. I hope to get two pots big enough to hold a gallon glass jar. I hope to set the pots up on two layers of offset bricks. On the first layer of bricks lay a 12 volt fan horizontally. The fan is direct drive off of a 12 volt solar panel. The zeer pot sits on the upper layer of bricks. The theory is that the zeer pot stays in the shade and the solar panel stays in the sun. The hotter the sun gets the faster the fan runs. The fan will increase the rate of evaporation cooling the pots. I am also interested in finding out if there is any improvement in performance using salt instead of sand between the pots. Salt is hydoscopic. It pulls moisture Out of the air. What I want to do is set this close to my chicken coop. Put a cup of lime desolved into a gallon of water and put it in the gallon jar inside the cooler. I hope to store my excess eggs in this cooler. They should keep for up to a year in the lime water. Keeping them cool doesn't hurt either. In the markets in North Africa they Make a bigger cooler like this for storing vegetables. They set four or five plastic laundry baskets on a brick floor then they build a wall of bricks around the baskets. Then they build a second wall four inches away from the first wall and fill the void with sand. They wet the sand and the bricks and it does the same thing as the zeet pot.. They put an insulated lid over the cooler. These are built under thatched roof shelters to keep the sun off of them. If you have a lot of stuff to keep cool this might be a better way. Big pots aren't cheap. Bricks are sometimes free.

Hi again! another idea I saw it in other video, that we make a hole large in the soil and put inside in the hole a pot, without any pot inside ! After put a little bit of water in the corner, Time to time ;) By by.

"Literally gets so hot in my yard the thermometer busted" Peak humanity right there. "Its inhospitable" "Nah, we'll make it work." 😂

taking it out of the direct sun will drop that temperature, too.

you can cool things with water and air you can boil things with sun and a reflective surface

Would potting soil work just as well?

thats a 20 degree centigrade temperature drop.. thats a lot

What about trying it in the shade?

White marble is cooling, I wonder if crushed white marble would work, and if there were some sort of tiny fan, such as a little solar fan blowing on it to speed up evaporation.

I was wondering if maybe you added some rock salt to the sand (as they do to freeze ice cream) , if it would be cooler? Just a thought! ?

Mohammed Bah Abba Nigerian invention won a Rolex Award for the Invention.

Pour a little sand then a little water till it reaches the top for total saturation

just like aztec gardening system

If you have to have it outside, I would place it against the house on the north side and that way it'll never see any direct sunlight and you might get lower temperature readings. The best thing to do is to probably bury it up to an inch of the rim.

Would this also work inside the house or does the pot really need to exposed to the sun to get proper evaporation going?

u forgot to mention best to use unfired pots as then the clay will soak some of the water in m on a mates property back in the mid 80s we used a single pot with a lid sitting on a saucer we kept filled with water .. lol we got use to boiling up green meat for dinner

You should make a whole clay house with an inner clay layer with sand in between and have some kind of misting or water system for the center you would never need air conditioning.

I fill mine with ice from the fridge ,it works so much better

Put it in the shade with a lid on it then the towel.

Would it be better to keep the frig in a canning room where it's 60-65* ?

how about if you put 2 pots inside the 2 pot fridge - with a gap of air inbetween? i would think it cools even lover - but will probably take longer to cool down.

I need this sort of cooler to keep my Amaryllis bulbs dormant for a couple of months. Did you say 40 deg fahrenheit it cools down to? That is 4.4 deg celcius! Does it really get that cool inside?

So, what would happen if you put one of these inside an even larger one? Would it cool the smaller one even more? I mean obviously there has to be a limit, but as long as its hot enough for evaporation to take place couldn't you theoretically just keep making larger and larger pots or sealed brick chambers with layers of wet sand between them in order to fit the smaller pots until evaporation is slowed to the point of not making a difference anymore? Am I over thinking this? Probably. I just find it interesting to think about.

Can I put canned food or food in glass jars in the Zeer? I have an extremely large clay pot that would take another large pot inside. Does it work as well with larger pots? Thank you.

Wonder how we could do this on a large scale for an outside dog house.. would be great! Could connect it to a 5 gallon refillable water tank to keep the sand wet. 🤔

I'm thinking of making an underground ice test.

Do you just put food inside there.

Thanks for making this videos

Viva las vegas! If you plant something in it, it should keep the soil cool yea?

Interesting but it would only work in dry climates.

125 degrees out 😮, Where do you live? Get’n 110-115 up here in northern cal above the Bay Area and that’s hot enough

Do you know if fine or coarse sand is more efficient?

living in AZ like: "it got so hot the thermometer exploded like in Looney Toons"

Inside a home where the average temp was 70-80 degrees, a 30-40 degree cooler difference would make it possible to keep milk cool. Thanks for posting, I've seen huge pots used in Africa so farmers can get their crops to market without the vegetables spoiling.

You forgot to put more salt that is the secret for a cooler pot and to dug a not to deep hole ablut 3 feet in your yard and put it inside with the towel and that will be very cool

why not use this technique to extend the ice life in an ice chest????

Bro it’s 2022 already good thing we have refrigerator 💀

Hey, I did not hear the sizes of the clay pots you used for this: can you provide it please?

Bro, I think blanketing the sides of the pot with a towel hinders the process of evaporation. The sides I think need to breathe to effectively draw out heat from the inside.

Will it work if we put soil/mud instead of sand (we cant get sand).

weight ?

How about using this to cool water for fog system

Is it resin

how the hell is it 125 degrees out? where do you live? mars?

Could you imagine how much energy one could save if houses in dry hot areas were built like this.

Do you change the sand often or no need?

Very "cool" lol Thanks for sharing.

How much cooler it would be if it were put into the ground?

U can also bury them into the ground.

125 degrees? Where the heck do you live?

How long does it keep the veggie fresh

Can you use this to cool the air in a room?

Better off the ground in the shade and in some area that catches a breeze.

About how long will it stay 40 degrees cooler?