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Evaporative AC and Other Alternative AC

Grainger Editorial Staff

They say that when you’ve got a hammer, every problem looks like a nail.

And when you’re thinking of how to cool a large shop, warehouse, or other building during the summer months, central air conditioning is one heck of a hammer. But all that cool, dry air comes at price—sky-high summer energy bills.

Fortunately, there are other tools—other types of cooling systems—that you can use. Whether you're trying to figure out how to cool a warehouse without AC, or just how to cool down a hot room in your building, you should keep these AC alternatives in mind. 

Evaporative Coolers

Recently, evaporative coolers (also known as “swamp coolers”) have become very popular, and it’s easy to see why.

Because evaporative coolers rely on the evaporation of water to lower air temperature, they are much less expensive to operate than traditional air conditioners, which use compressors and refrigerants.

Evaporative coolers typically use 75% less energy (and therefore cost less to run) than central air conditioning systems according to the Department of Energy. They are also generally less expensive to install.

But there are drawbacks, too.

  • Evaporative coolers can require more frequent maintenance than air conditioners.
  • Evaporative coolers need dry outdoor air to be at their most effective, and they may struggle when temperatures are over 100 degrees.

Sizing an Evaporative Cooler

Evaporative coolers are rated by the volume of air that they can bring into a space—in “cfm,”or cubic feet per minute.

According to the Department of Energy, manufacturers recommend coolers that can deliver 20 to 40 air changes to the space per hour.

Fans and Powered Ventilation Systems

Using air circulators, ceiling fans, ventilators, and exhaust fans, a whole-building ventilation system prevents hot, stale air from getting trapped indoors. The idea is simple, but don’t overlook it. Active ventilation systems can be powerful cooling tools, and they also help maintain higher indoor air quality. 

  • A ventilation system is the most energy efficient—and therefore least expensive—way to cool a building.
  • Ventilation works best when there’s a big difference between daytime and nighttime temperatures.
  • Unlike central air conditioning, ventilation systems don't pull moisture out of the air. When necessary, dehumidifiers can reduce excess humidity, though their energy use can be significant.
  • Adequate ventilation helps avoid poor indoor air quality, which can lead to lower productivity and even health problems. Learn more about the health consequences of poor indoor air quality.

Step Up Your Ventilation System

If you’d like to improve your building ventilation, get an overview of ventilation systems and how they can prevent heat stress.

You can also learn more about: 

The information contained in this article is intended for general information purposes only and is based on information available as of the initial date of publication. No representation is made that the information or references are complete or remain current. This article is not a substitute for review of current applicable government regulations, industry standards, or other standards specific to your business and/or activities and should not be construed as legal advice or opinion. Readers with specific questions should refer to the applicable standards or consult with an attorney.

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