Evaporative Cooler Savings
Check out our store for energy conservation books and online training for energy auditors and other job skills.
Residential Energy 5th Edition
$45.00
Consumer Guide to Home Health
$12.00
Homeowners Handbook to Energy Efficiency
$24.95
If you live where summers are hot and dry, evaporative coolers (also known as swamp coolers) can keep your home comfortable less money than air conditioner. The lower your summertime humidity, the more successfully an energy efficient evaporative cooler can cool your home. Evaporative coolers have large fans that move air through water-saturated pads. These absorbent pads are made of aspen wood fibers, glass fibers, or specially formulated paper. A water pump in the reservoir pushes water through tubes into a drip trough, which then drips water onto the pads. The water in the pads evaporates, reducing the temperature of the incoming outdoor air. As cooler air is forced into the house, it pushes warmer air out through open windows or through specialized vents called up-ducts. Unlike central air conditioning systems, which are most efficient when your home is sealed up, evaporative coolers provide a steady stream of fresh air to the home. On cool nights an evaporative cooler can cool your house without using any water, by using a fan -only control setting.
So which is more costly: the large electrical consumption of a central air conditioner, or the combined electrical and water consumption of an evaporative cooler? Evaporative coolers use only18 to 25 percent of the electrical energy consumed by air conditioners, and evaporative coolers cost about half as much as air conditioners to install. Evaporative coolers compare in performance to air conditioners with a Seasonal Energy Efficiency Ratio (SEER) of between 30 and 40. The most efficient air conditioners have a SEER rating of about 12. The University of Arizona performed a study of evaporative cooler water use. They found that the cost of water consumed by these efficient low-tech appliances added only a minimal cost to their operation, especially when compared to power-hungry air conditioners. The study showed that the typical evaporative cooler consumed about 1500 kilowatt-hours of electricity per summer, costing about $150 at current rates. The cooler’s water consumption added an average of $54 to a municipal water bill over the course of the summer, for an electricity-and-water total of $204 per year. The central air conditioners in the study consumed an average of 6000 kilowatt-hours of electricity per summer, or about $600 at current rates. That $400 savings, year after year, makes evaporative coolers an attractive option for families all across the sun belt.
An added benefit of evaporative cooling is that it works best in the hottest time of the day. When the outside temperature increases, the humidity normally drops. In the early morning, for example, the temperature may be 70 degrees, with a relative humidity of 60 percent. By mid-afternoon, when the temperature has climbed to 90 degrees, the humidity may well have dropped to 30 percent. These dry conditions help evaporative coolers work more energy efficiently.
The use of low energy cooling methods such as evaporative coolers has an important added benefit for consumers and utility companies alike. Air conditioning adds a large summer “peak load”
