Places near ocean, river, and lake on Earth are cool due to natural evaporation of water. When hot air blow across water surface, water molecules absorb heat from air and evaporate, thus lowering the temperature of air above the water and making us feel refreshed and cool.
Evaporative air cooler utilize this principle of water evaporation and heat absorption for cooling. Specifically, hot, dry air passes through cooling pad (honeycomb pad layer made of special material that effectively increases touch area between water and air by 100 times). As water evaporate and absorb heat, air temperature is significantly reduced, with cooling decrease effect of 5-12 degrees Celsius. Cooling effect is most obvious, particularly during hot, dry days of summer.
