The device uses an evaporative cooling terracotta section and a moisture condensing metal section. The terracotta section evaporates water through it's microscopic pores making the water in itself colder, the heat transfers to the condensing metal section which cools the air and condenses water on it's surface and pours down to the terracotta section.

The terracotta section is placed in a chimney. The top of the roof is connected to the top of the chimney to evacuate the hot air that rises to the top.

The outside air passes the condenser, cooling it and condensing water for the terracotta (2). The cooled air is heated by person or other heat source and rises (3). The hot air exits through the chimney (4). Cold, dry air passes the terracotta as it's pulled by the chimney updraft , causing the water to evaporate and cool the remaining water, the coldness is sent to the condenser by heat pipe.(5).
-- flireferret, Sep 08 2024

diagram https://imgur.com/a/h6OcyoX
fits with the numbered descriptions [flireferret, Sep 08 2024]

Clay pots. https://www.enginee...ithout-electricity/
Who knew? [2 fries shy of a happy meal, Sep 11 2024]

MIT and Berkeley offerings https://youtu.be/EG...si=-aF4JnM_9nHvhZD4
They should have looked a little closer. [minoradjustments, Sep 13 2024]

So it's a swamp cooler with an extra step?
-- Voice, Sep 08 2024


First of all, auto-bun for anybody who puts up illustrations of their ideas, [+] but I'm a bit confused. So is this a passive system with no fans, the air moving around by nature of its temperature, up when hot, down when cool?
-- doctorremulac3, Sep 08 2024


There's a fellow in India who won 200,000.00 dollars inventing a double walled clay fridge which would stay at exactly two degrees as long as water was dripped on the cloth covering the double walled vessel and it stayed in the shade.
-- 2 fries shy of a happy meal, Sep 09 2024


…and was kept inside a refrigerator set to 2 degrees.
-- doctorremulac3, Sep 09 2024


//the coldness is sent to the condenser by heat pipe.//

I'm not sure what process sends coldness *up* a heat pipe.
-- pertinax, Sep 09 2024


Isn't this the general principle of a dehumidifier?
-- pocmloc, Sep 09 2024


Well flireferret, you've got everybody interested here. Confused but interested.
-- doctorremulac3, Sep 10 2024


//water was dripped on the cloth covering the double walled vessel and it stayed in the shade.//

and the ambient humidity was cooperative.
-- bs0u0155, Sep 10 2024


Yea, relative humidity is everything. That water's gotta have someplace to go.
-- doctorremulac3, Sep 10 2024


//That water's gotta have someplace to go//

I grew up in a NW English town so routinely damp that a whole silk industry flourished there, dry air makes silk snap easily apparently. Anyhow, it makes heat pump heating systems more powerful for good parts of the year as the outside evaporator cools and causes condensation of the near 100% humidity, you end up with a ton of free heat from the phase change.
-- bs0u0155, Sep 10 2024


//…and was kept inside a refrigerator set to 2 degrees.//

No. It's true.
You can make a fridge from two nested unglazed, (another strange flag), clay pots, some dirt, a towel, and enough water to continuously evaporate. [link]

Apparently it will only cool contents to ten degrees lower than ambient temperature, but it works just fine in the shade.
-- 2 fries shy of a happy meal, Sep 11 2024


(+) btw.
-- 2 fries shy of a happy meal, Sep 11 2024


Regarding the clay fridge - this must work using evaporative cooling. Cooling water in unglazed pots is an old trick.

I don't know what the double-wall you mention is for. If you've got water dripping onto cloth on the outside, the walls won't be that critical a component. I guess you need some conductivity for heat, and maybe some thermal mass would help draw heat out of stuff you put in more quickly (and deal with heat loading during the day). So you couldn't use e.g. expanded styrofoam. But many materials would suffice.

Anyway, this is probably great in India with routinely very low humidity. It would work less well in England - say, bs0u0155's town with ~100% humidity.
-- Loris, Sep 11 2024


//I don't know what the double-wall you mention is for.//

The space between the two clay pots is filled with soil. It allows for more water to be contained than a single pot alone could absorb, and it insulates the interior contents.
Yes, relative humidity would be a factor.
-- 2 fries shy of a happy meal, Sep 11 2024


//The space between the two clay pots is filled with soil. It allows for more water... // and ample mold-growing volume, just like the near-continuously watered mulch covered planters in front of my building.
-- bs0u0155, Sep 11 2024


What would keep the moisture passing the condenser ON the condenser? Any breeze at all would just steal the heat and move on, not leaving anything behind.

There were a couple of popular ideas for condensing H2O from relatively dry air using the delta between the ground temp and the air temp. A buried pole format. It raised a lot of money before they proved it couldn't work. Another idea uses solar to extract H2O from passing air, even in the desert! This one is from MIT and Berkeley, and is thoroughly debunked by the dude in the link. Volume is the problem, balanced by the energy needed to get it out of the air.
-- minoradjustments, Sep 13 2024



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