3 Reasons Swamp Coolers Are Not as Gross as They Sound

After such a brutal winter here in parts of the U.S., the thought of summer is probably one you’re excited by! Then again, summer also often brings with it unbearable heat and a bump in our electricity bills from running the air conditioning to keep us cool. Well, if high energy costs from traditional air conditioning has you less than enthused, a swamp cooler may be the answer! Otherwise known as evaporative coolers, swamp coolers can lower indoor temperatures by as much as 30 degrees and use as much as 75% less energy than traditional AC systems.

If you've ever licked your finger and held it up in the air to test the wind, you know what evaporative cooling is. When air passes over water, the water evaporates, becoming vapor, which cools the air. Swamp coolers combine this natural cooling effect with a continuous, energy-efficient air flow system. Swamp coolers are an "open system" that is constantly pulling fresh, hot outside air into it, passing it through water with a fan, and blowing the cooled air into the house.

A traditional air conditioner is a closed system in that it circulates air that is inside the house through a series of coils that are cooled by a refrigerant, such as Freon. The cooled air is then circulated through the house over and over again. The AC unit's mechanical process of cooling the air using Freon also creates heat, which is pumped outside the house.

Swamp Cooler Benefits

Swamp coolers have three main benefits over conventional AC:

1) Versatile, Inexpensive and DIY Options: Swamp coolers can be almost any size and they have many applications, from buildings to cars. They can be made as simply as using a fan and cups of ice water. Indeed, in the 1940s and 1950s, before air conditioning became standard in automobiles, swamp coolers were designed to bolt onto an existing car's window. The makeshift air conditioner pulled fresh water through a wick from a small self-contained reservoir in the unit and cooled the inside of the car as it drove along.

2) Reduced Energy Consumption: The reason swamp coolers are much more efficient than conventional AC units is that power consumption is limited to the fan and the water pump. In addition to the reduced energy consumption, evaporative coolers have low installation and maintenance costs. In dry climates, a swamp cooler has the additional benefits of adding moisture to the air.

3) No Harmful Refrigerants: Also, because water acts as the swamp cooler's only refrigerant, swamp coolers are free of the ozone damaging refrigerants that are banned by the Montreal Protocol (and referred to within LEED), as well as the less ODP and GWP impactful refrigerants found in most air conditioning units. Down-draft units are typically installed in the roof, but wall-mount and portable units can be used to cool smaller spaces or just single rooms. One of the added perks, regardless of the type of cooler you choose, is that the fresh airflow helps to keep homes free of stagnant air.

Problems with Swamp Coolers

But now for the caveats – these systems aren’t suitable for everyone, or rather, every location.

Oddly, while the name suggests it might be used to cool a swamp, areas of high humidity (e.g. swamps and swamp-like locales) are not ideal for this type of cooling system. Swamp coolers are most effective in climates with an abundance of hot, dry air (the Rocky Mountain region currently has the highest installation rate in the country). And, if a swamp cooler is not maintained, it can become a breeding ground for mosquitoes, or worse, Legionnaire's disease or sick building syndrome.

If your region is one of a hot, dry climate, you’ll need to calculate the necessary cubic feet per minute (CFM) cooling capacity to determine which system is most appropriate. Luckily, the equation is a simple one: Multiple the square footage of your home by the height of the ceilings and then divide that number by two. For example, if you have a 2,000 square foot home with 8 foot ceilings, then 16,000 ÷ 2 = 8,000. This indicates that you will need a unit rated 8,000 CFM or higher. You can get swamp coolers at Home Depot.

However, as you probably guess, you can also build your own swamp cooler. Here's a video on how to do just that!