Swamp Cooler vs. Air-conditioning
Although hot air coolers and air conditioners were invented to turn hot air into cold air, the science behind each method is quite different.
What is a swamp cooler?
It’s just another name for an evaporative cooler. Water is used to dampen the absorbent pads around the sides of the cooler. A fan or “squirrel cage” draws outside air across the pads, and the air cools as the water in the pads evaporates. The main benefit of this type of cooler is that you only need to turn on a water pump and fan to pull air through the pads.
They typically use between three and 10 gallons of water per day. That’s equivalent to a few toilet flushes or, on the high end, a short shower.
Unless the relative humidity is below 30%, evaporative coolers are not very effective. They do well in the Southwest, West Texas, and parts of Idaho, Washington, Colorado, Wyoming, and Montana. In those areas you should be able to achieve a 20 degree difference between outside and inside.
Also, for an evaporative cooler to remain effective, it must push as much air out as it puts in. This means keeping a window open. If you don’t, the humidity will increase and so will the temperature of the air leaving the cooler.
Air conditioning, on the other hand, is popular because it will reliably dehumidify and cool the air, no matter where you live. This is how an air conditioner works:
The compressor compresses cold freon gas, causing it to become hot freon gas under high pressure. This hot gas passes through a set of coils so it can dissipate its heat and condenses into a liquid.
Liquid Freon passes through an expansion valve and in the process evaporates to become cold Freon gas at low pressure. This cold gas passes through a set of coils that allow the gas to absorb heat and cool the air inside.
Mixed with the freon is a small amount of light oil that lubricates the compressor.
Swamp cooler vs air conditioner: which is cheaper to operate?
In our friendly contest, the swamp cooler wins handily. For similarly sized units, even an Energy Star rated air conditioner uses 4-5 times the energy needed to run a hot water cooler.
The difference is the amount of energy needed to power an air conditioning compressor versus the electric motors used in an evaporative cooler.
Which is better for the outdoor environment?
Unless you think the soon-to-be-banned leak of R-22 refrigerant into the atmosphere from your air conditioner is a good thing, the evaporative cooler wins again. The Swamp Cooler maintains a green profile by mimicking nature’s way of cooling.
How an air conditioner or evaporator cooler affects your home’s indoor environment is determined by how the air circulates. Although an air conditioner recirculates the same air, this is helpful in controlling allergens like dust and pollen.
Since an open window is necessary when running an evaporator cooler, it will let in what the air conditioner won’t let in.
Swamp Cooler vs Air Conditioner: Which Wins?
I think hot air coolers are a good option as they are relatively less expensive and much cheaper to operate than air conditioning, as long as you live in Phoenix, Arizona. But if you call Little Rock, Arkansas home, no one will talk you out of your air conditioner.