Why use an evaporative cooler?

What Are the Benefits of Evaporative Cooling?

I've been asked this question many times over the years and even with the increasing efficiency of forced air conditioning units, there are still many reasons why evaporative cooling is still a useful and beneficial cooling option, especially in the Southwest.

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 $10000 to have installed on a 2000 square foot house. An evaporative cooler for the same size house can be installed for as little as $2500. 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 indoorcomfortsupply.com

Bryan Robert is the owner of Indoor Comfort Supply in Phoenix, AZ and has over 30 years experience working with evaporative cooling and air conditioning systems.