Evaporative cooling is still popular today, even though it is an old technology. If you have ever tested the wind by waving a wet cloth in the air, you used evaporative cooling. The same principle cools your body off after swimming, in the same way it powers one of the oldest and easiest forms of air conditioning. Contemporary evaporative coolers trace their origin back to ancient Egypt and are known in the United States as swamp coolers. They are efficient, affordable and environment-friendly, though they have some limitations, that is why your standard air conditioner will still be useful.

Unfortunately, evaporative air coolers cannot operate everywhere. In order to work, they need a hot, dry climate, so that water would evaporate more efficiently and add coolness and humidity to the air. In the USA swamp coolers function best in the dry southwest. In 1998 there were more than 20 million evaporative coolers around the world, with four million of those in the United States alone. For example, in the states along the Rocky Mountain Range, the evaporative coolers could be found in 26 percent of the homes according to the Energy Information Administration's 2001 appliance report.

Swamp coolers are built around a simple, cost-effective technology that has been in use for a long time. If the laws of evaporative cooling worked great for the pharaohs, they can still work for you. Choose an evaporative cooler that will best suit your needs today!