Swamp Cooler vs. Air Conditioner: The Best for Dry Heat

Never heard of a swamp cooler? You're not alone. Sometimes called an evaporative cooler, these efficient appliances can help beat the heat in certain climates and may be a better option than air conditioning for some homes. With record-breaking heatwaves and high electric bills, consumers need to find ways to stay cool without paying a fortune.  

Here’s what you need to know about swamp coolers vs air conditioners.

Swamp cooler vs air conditioner: mechanical differences

A swamp cooler lowers your home temperature by adding humidity to the air. It works by passing air over a damp pad, letting the moisture from the pad evaporate, which cools the air by 15°- to 40°F before it is directed into the home, as per the DOE. Because of this, swamp coolers are only suitable for low-humidity areas, making them good options for homes in the Western and Southwestern parts of the country. 

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Unlike an air conditioner, a swamp cooler is an open system. This means that you’ll need to have doors or windows at least partially open while running the cooler. Swamp coolers “rely on the flow of air through the building to direct the cool air, and since they always need hot, dry air to evaporate the water, it needs to displace the air already in the house,” according to HowStuffWorks. The warm air has to escape somewhere. That may be a deal-breaker if you have allergies and want to avoid pollen or pollution.

Swamp coolers can be installed on the roof, in a window or on the ground, although most commonly, they’re installed in a down-flow arrangement on a roof, reports the DOE. Small coolers can be installed in a window to heat a specific room in your home, and small, portable evaporative coolers on wheels are now available.

On the other hand, air conditioners cool your home by transferring heat from the interior of your home to a warm outside environment. And it’s a bit more complicated. Here’s how it works, according to the DOE. Basically, an air conditioner contains a liquid refrigerant that evaporates in an interior evaporator coil, “pulling heat out of indoor air and cooling your home.” After which, “the hot refrigerant gas is pumped outdoors into the condenser where it reverts back to a liquid, giving up its heat to the outside air flowing over the condenser's metal tubing and fins.”

Unlike a swamp cooler, installing air conditioning is a more difficult and lengthy process, but can be used in homes in both humid and arid climates. Although they do tend to dry the air.

Upfront costs

The unit's price is a big difference between swamp coolers and air conditioners. How much each cost ultimately depends on the size and type of the unit and how it is installed. However, on average, swamp coolers have lower installation costs, making them cheaper.

The average cost for a swamp cooler installed in a 1,500 sq. ft home is $3,900, while an air conditioner averages $5,000, according to Fixr.

Here’s a price breakdown for swamp coolers, as per Fixr. 

• Portable swamp coolers: Range from $100 to $1,500 or more
• Mounted swamp coolers: range from $500 to $1,500
• Window swamp coolers: Range from $300 to $1,000
• Installation costs: Range from $100 (for a simple freestanding unit) to $1,000 (for a mounted unit)
• Overall costs: Range from $100 to $2,500

And here’s a price breakdown for air conditioners, also courtesy of Fixr.

• Portable unit: Range from $200 to $700
• Window unit: Range from $300 to $1,200
• Installation costs: Range from $100 (do it yourself) to $800 (professionally) 
• Central units: $1,500 on average, installation costs range from $2,000 to $5,000
• Overall costs: Range from $200 to $6,500

Cost to run and efficiency

Electricity: A swamp cooler uses 60% to 80% less electricity than a standard AC unit, meaning big savings on electricity costs. That efficiency is becoming an ever-more important factor for consumers. According to the U.S. Energy Information Administration (EIA), you can expect to pay more for electricity this summer than last year. The EIA forecasts that residential customers’ monthly electricity bills will average $173 from June to August. Last summer's average was $168. 

The EIA also found that monthly costs remain high in dry regions of the country, where swamp coolers might be a good option. The Southwest has the highest average monthly electric bill of $203. 

Water: One downside of swamp coolers is their use of water — often a scarce commodity in the arid environments where these appliances are most useful. Estimates of swamp cooler water use vary widely. While air conditioners do not require any water, swamp coolers may use between about 3,000 and 12,500 gallons of water annually, depending on location, size and other factors, according to the New Mexico Office of the State Engineer.

Swamp cooler vs air conditioner: sustainability differences

Overall, swamp coolers are more eco-friendly than air conditioners. They don’t contain any toxic chemicals and typically have lower levels of CO2 and greenhouse gas emissions. If refrigerant from an AC unit leaks, it can have a significant impact on the environment. For example, R-410A, a common refrigerant, has a global warming potential (GWP) of 4,260 over 20 years, according to the Natural Resources Defense Council (NRDC). If a pound of this refrigerant leaks into the atmosphere, it packs 4,260 times the climate wallop as a pound of CO2. 

So, if you live in a dry, arid region of the country, not only will using a swamp cooler save you money, but it’ll also pose less of a risk to the environment and reduce your carbon footprint.

Bottom line

Simply put, swamp coolers cool your home by adding humidity to the air, while air conditioners cool your home by pulling heat from inside your home to the outside. And while swamp coolers use significantly less energy and are cheaper than air conditioners, they have a huge drawback. They're most effective in dry climates and aren't suitable for areas with high humidity levels. They may also consume significant amounts of water. However, if you live in a dry climate, such as in the West or Southwest, you can reduce your carbon footprint and help the environment by installing a swamp cooler.

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