An evaporative cooler has a lot of advantages over a standard air conditoner because it has a lower cost of installation, requires less maintenance and operates with less energy. Because they are less common in some parts of the country, it seems like a lot of people do not know how an evaporative cooler works. Evaporative coolers are also known as swamp coolers, and they provide effective cooling by taking advantage of the natural process of water evaporation. Condensation is combined with an air moving system to cool the surrounding air. This style of air conditioning has its roots in early cooling methods in the American Southwest. Because electricity was rare in the early 20th century and because inventions such as air conditioning did not exist yet people kept cool by sleeping outside during the summer on screened porches. Wet bed sheets were hung around the porch on the screens and they would use fans to pull the night air through the damp cloth to make a cool breeze into the room. The temperature thus lowered, they could sleep comfortably without having to soak their clothing or get wet from the mist. This sensation can still be felt on patios that have misting systems installed. Skin gets slightly damp from the mist and the fans force air to cool.
A swamp cooler works in a very similar way to the enclosed porch with wet sheets and fans. The motor in the unit pulls fresh outside air through moist pads, using evaporation to cool the air and fans to circulate the air through the building. The room temperature often decreases by 30 degrees when this method is used. An evaporative cooler is perfect in arid dry environments, especially for those who suffer from allergies caused by dust, pollen and dry air. Unlike a standard air conditioner, swamp coolers leave a small amount of humidity in the building, reducing the need for humidifiers.
Swamp coolers also use far less energy than central air conditioners because evaporative cooling employs water’s heat of vaporization. The motor does not have to work as hard to cool the air because it is aided by the water. The temperature of dry air is lowered significantly through the energy of the transition of liquid water to water vapor, which requires less electricity because the energy, rather than the air itself, is recycled, coming from the transition itself. Air conditioners, on the other hand, merely reuse the air already inside the building, which means that more electricity is required to cool the air in the first place and then distribute it within the building.