Swamp Cooler

Evaporative Coolers, called swamp coolers are a sensible alternative to cool a home in dry climates. With 100 degree outside air and 10 percent relative humidity, these units will cool to around 70 degrees. Operating cost is about 1/3 that of an air conditioner. Installation cost is 1/5 to 1/6 that of air conditioning, however maintenance is higher.

But there's a catch...they only work well in a dry climate. Southern Arizona is ideal.

They also add moisture to the air which increases the comfort level.

By comparison, air conditioning dries the air, enabling higher set points for the air conditioning thermostat. For example we are comfortable with a set point of 79 degrees. We also have ceiling fans in most rooms that circulate the air and make people feel cooler.

I prefer air conditioning because it is more controllable and continues to work well in the more humid Monsoon Season (coming in July). Air Conditioning has helped make practical the explosive housing growth in Southern Arizona.