((Note: this is post of mine from a different site that is about a year old, but thought I would share it here too in case it helps anyone))
Old technology is once again getting attention, and this time it’s air-conditioners made out of terracotta clay.
“She was inspired by the Palestinian Jara, a traditional clay water container that is hung from the ceiling to cool water and cool the air. Specifically, the water contained in the hollow internal structure moves outward through the porous clay walls. With the heat of the air, it evaporates and is transformed into water vapor. This reaction absorbs heat from the surrounding air, cooling the water, the material itself and consequently the air in the room.” Forbes India In regards to Yael Issacharov.
There are two unrelated people currently being mentioned for promoting their designs using this technology; Monish Siripurapu(from India), and Yael Issacharov(from Israel).
Monish Siripurapu’s design is based off a beehive and uses a small pump to create a beautiful water fountain that both cools the air and can be used for gardening.
Yael Issacharov’s design uses no electricity, and instead relies on the naturally porous nature of the clay.
For dry and hot climates, this old technology could provide cooler air at an affordable price. The clay is readily available almost entirely world-wide, making it accessible and inexpensive.
"The humid clay traps some heat the air and the surrounding air gets cooled down to around 6-10⁰ C due to the process of evaporative cooling.“ EcoIdeaz in regards to Monish Siripurapu
Videos with more info:
Based on this information, I am wondering if a terracotta pot and a fan would have the same effect for a small room. Here’s a drawing of mine to help explain what I mean:
They do not work well in already humid environments but in a hot and dry climate they do quite well. It absolutely does add to the humidity (obviously) but speaking from experience I’d rather have a evap cooler than not if my AC is out.
The largest difference in utilizing one over AC is that they rely on airflow so you need to actually ventilate the area you are cooling as compared to AC where you want a sealed space.
The main driver is power efficiency. Only thing they are doing is running a small water pump and a big fan.