Evaporative coolers are growing in popularity, thanks to their many benefits over traditional air conditioners. Amongst the benefits cited in comparison to traditional air conditioners are:

-Lower energy consumption
-Quieter operation
-Does not use polluting refrigerants
-Simple operation, and easy, cheap repair
-Can help humidify a home in drier conditions
-Improved air filtration

Evaporative coolers are basically large fans and water-wetted pads. The evaporative cooler works by pulling fresh air in from outside, cooling it approximately 20 degrees as it passes through the wet pads, and blown into the house with the fan. Since water is used to cool, evaporative coolers typically work best in low humidity areas of the country or seasons. Evaporative coolers also have the side benefit of helping with air filtration, as many particles are removed as air is passed through the wet pads.