Evaporative air cooling is a natural, age-old practice.
People living in the desert use various methods of evaporative cooling (where evaporation of water is used to cool the air) when temperatures soar. The practice is not new – in the old days, people would often hand water-soaked bed sheets or blankets in windows and doorways and rely on natural wind or fans to pump air through the moist cloth to cool the room.
Evaporative air coolers – a refined concept of the age old practice – provide an alternative to refrigerated air conditioning by being:
The 3-step air cooling process is very simple and no less effective than modern refrigerated air-conditioning technologies.
A simple air moving system pulls fresh outside air and drives it through the moist pads. (The water / air cooling pads have replaced bed sheets.)
The water in the pads evaporates, bringing down the temperature of the air passing through the pads.
The blower then blows the cool air into the room.
Why natural evaporation lowers temperatures?
Evaporation takes place throughout the day. For example, we perspire in hot weather and the water vapour produced by sweating takes the heat away from our body as it is exposed to air. Whenever dry air passes over water, the water is absorbed by the air. That is why evaporative cooling naturally occurs near waterfalls, rivers, lakes and oceans. The hotter and drier the air, the greater is the water absorption.