Evaporative air coolers include two motorized components: a pump and a fan. The pump circulates water around the unit and saturates a honeycomb-shaped irrigation pad. The fan blows air through the wet irrigation pad, causing the moisture to evaporate into vapor. The conversion of heat energy into evaporative energy results in a coolness in the outgoing air. The perfect example of this is a lakeside breeze: the air along a lake or waterfall feels cooler than the air inland. This is because heat has been converted into water vapor.