Evaporative coolers use a relatively low amount of energy, especially when compared to air conditioners. It has been estimated that a 1,600 square foot home will annually use 1,500 kilowatt hours for an evaporative cooler, versus 6,000 kilowatt hours for a refrigeration system. Thus, evaporative coolers can help save energy and money.
Table 1: Estimated energy usage and cost for evaporative coolers and air conditioners operating in a 1,600 square foot home.
||Cost per kWh
Although evaporative coolers have relatively low energy use, there are a few things you can do to insure that you avoid wasting energy (and water). Be sure that you install a thermostat and/or timer on your evaporative cooler so that it only functions when necessary. In addition, many coolers are available with two-speed blower motors. Often you will only need your cooler to operate at a low speed, which is the more energy efficient mode.
Some homes have a combined system where the same ductwork is used for an evaporative cooler and air conditioner. In this case, make sure that you don’t precool the air in the house using the evaporative cooler before turning on the air conditioner. Refrigeration systems use more energy if they have to remove moist air brought in by evaporative coolers.
“Evaporative cooler water use” by Martin Karpiscak of Arizona Cooperative Extension. Accessed April 11, 2003.
“Installing and Maintaining Evaporative Coolers” Home Energy Magazine Online May/June 1996. Accessed May 1, 2003.