Some information about
evaporative coolers, the
science behind the
technology, the history
of their use, and
can be found in the links
here. We hope you find
About Evaporative Cooling
Evaporative Cooling - What Are the Benefits?
I've been asked this question many times over the years and even with the increasing
efficiency of forced air conditioning units I can still come up with several reasons why
evaporative cooling is still a useful and beneficial cooling option, especially in the
First and foremost is the initial installation cost. Rooftop and split system air conditioning
units are subject to a government mandated efficiency minimum that has forced air
conditioning manufacturers to upgrade to more expensive refrigerants, components, and
cabinet sizes. This drives the cost of air conditioning units higher and higher. Meanwhile,
evaporative cooling unit costs have stayed fairly low. A typical rooftop air conditioner can
cost more than $6000 to have installed on a 2000 square foot house. An evaporative
cooler for the same size house can be installed for as little as $1500. Even less if you are
able to do it yourself.
Second, evaporative cooling is a green technology. Evap coolers use up to 90% less
electricity than air conditioning units. They also do not use chemical refrigerants that have
been linked to upper atmosphere ozone depletion. Coolers only use water and air.
Another nice benefit of evaporative cooling, which is actually subject to preference, is the
addition of moisture to the conditioned air. The moist air can feel very comfortable,
especially in dry climates like the Southwest United States. Air conditioning actually
removes moisture in the air as it cools it, leaving the conditioned air very dry.
Now for the math.
While the operating costs associated with air conditioning have dropped dramatically over
the last ten years, evaporative coolers still have them beat hands down. A standard
residential evaporative cooler on a 2000 square foot home, operating on 230 volts pulls
about 6.8 amps which equals 1.564 kilowatts. If your cooler ran for 10 continuous hours at
an average rate of 11 cents per KwH it would cost $1.72 per 10 hours.
A 5 ton, 13 seer package heat pump A/C unit on the same 2000 square foot home pulls
about 32.7 amps at 230 volts for a total of 7.521 kilowatts. 10 hours at 11 cents per KwH
would be $8.27 per 10 hours.
What that boils down to is that even a high efficiency A/C unit costs 4.8 times more to run
then a similar sized evaporative cooler!
So, is it worth it to have a new evaporative cooler installed or to fix up the existing one?
Absolutely! It's all in the numbers.
For more information about evaporative cooling check out
Bryan Robert is the owner of Indoor Comfort Supply in Phoenix, AZ and has over 20
years experience working with evaporative cooling and air conditioning systems.