I-Cool works by endothermic reaction (a reaction that consumes heat), so this evaporative Air Cooler sucks air through a wick saturated with water. As the air flows through the wick, some of the water evaporates into the air, consuming the heat that was in the air. An air stream is then blown out the front of the unit and is considerably cooler than the current room temperature! This is not an air conditioner and therefore uses much less energy.