Evaporative cooler combined with Peltier elements to produce electricity
Image credit: Lynn Davis
Darko SavicMay 17, 2021
The idea is to generate electricity via the Peltier elements (Seebeck effect) coupled with an ancient passive cooling method.
In addition, the same cooling method could be used to make this almost passive atmospheric water generator into a fully passive atmospheric water generator.
By 400 BCE, Persian engineers were building yakhchāls (ice pits) in the desert to capture and store ice. A Yakhchāl is an ancient passive evaporative cooler. The structure has a dome-shaped evaporator above ground and a cold storage area below ground.
During evaporation, the warm air molecules move faster and evaporate from the opening on top. This leaves the slower-moving, colder molecules behind. The result is a significant difference in temperature between the outside air and the air inside the ground storage area.
Peltier elements and Seebeck effect
Thermoelectric devices or Peltier elements use the Peltier effect to create a heat flux between the junctions of two materials. The same can be used in reverse (Seebeck efffect) to convert the difference in temperature into electricity.
Electricity production via Yakhchāl and Peltier elements
Holes would be dug on the side of the cold storage area of a Yakchal. A barrier made of many peltier cells would replace sections of cold storage area wall. The hot outside air would reach one side of the Peltier elements while the cold inside air would reach the other side - thereby producing electricity via the Seebeck effect.