Why some homeowners prefer evaporative cooling over central AC
The basic technology behind evaporative cooling has been around since the days of ancient Egypt. Back then, wet blankets were hung across the doors of homes, cooling the hot dry air as it passed through. Simple, economical and efficient, those same principles are what make today’s evaporative coolers an excellent choice for cost-effective home cooling. But don’t worry, these days you don’t have to hang any blankets.
So what makes evaporative cooling a preferred choice over central air conditioning in certain situations? While both provide whole-home comfort, evaporative cooling has some real nice advantages. First, it’s a far more efficient technology. Evaporative coolers typically use 25 to 50 percent less energy than central air conditioners to cool the same amount of space. They also cost about half as much to purchase and install. The conditions do have to be right to use this technology in your home so let’s dig a little deeper and find out if you’re a candidate.
Why are evaporative coolers so efficient? Science, of course. Let’s go back to ancient Egypt for a minute, and the wet blankets. It’s pretty easy to see how this simple process works to cool hot air. Evaporative coolers use essentially the same technique, modified over the years for maximum efficiency in the modern home.
The main component of an evaporative cooler is the blower. A fan pulls air from outside the home and pushes it inside. On its way, the air passes through a set of damp pads, and that’s where the evaporation process takes place. The water in the pads evaporates and cools the air by about 20 degrees before flowing it throughout the home.
It takes two (mechanical parts) to make a thing go right
Hard to believe but the high-efficiency pump and fan are the only moving parts in an evaporative cooler. There’s no compressor and none of the complicated refrigerants you’d find with an air conditioner. Because of this straightforward setup, evaporative coolers save considerable energy and money, so you can enjoy the comforts of home without a soaring energy bill.
Is my home a good fit?
It’s pretty simple. The most suitable environment for evaporative cooling is a dry climate with low humidity, because the system requires hot, dry air to evaporate the water. If you live in an area like that, you’re a perfect match. There are some pros and cons to consider before fully committing though.
On the plus side, we’ve already discussed the huge energy savings, low price point and low cost of installation. These systems are also great for the environment because they don’t use refrigerants or ozone-harming chemicals. And in the dry climates, where they’re suited best, they provide an added benefit of humidifying harsh, dry air.
Because the system relies on airflow, one of the negatives is that you’ll need to leave a window open to allow hot air to escape. You can get around this by venting through the ceiling or attic, however, if you’re willing to pay the additional cost. Frequent maintenance is another downside, though most routine maintenance you can do on your own if you wish. Also, in extremely high temperatures the system may not provide enough cooling, but it should be more than adequate on most summer days.
It’s a good idea to look for a unit that has at least two or three fan speeds to allow for operation at lower speeds when it makes sense. A vent-only option is also nice to have so the unit can serve as a whole-house fan without water usage.
Evaporative coolers are available as rooftop/downdraft units, wall or ground-mounted, window-mounted, or as portable room units. A ducted evaporative cooling system is also a great option if you’re looking to replace a central air conditioner.
When it comes to sizing, evaporative coolers are measured by CFM. This measurement describes the cubic feet per minute of air that the unit can blow into the home. The general rule of thumb is to have 2 to 3 CFM per square foot of space you want the system to cool. So if you are looking to cool a 500 sq. ft. space, you should look for an evaporative cooler that has 1,000 to 1,500 CFM.
Rocky Mountain Power offers up to $150$1,000$200 cash back on qualified units designed to save energy and money. Be sure to check the list of qualified evaporative coolersqualified evaporative coolersqualified evaporative coolers, including details on how to earn cash incentives, if you think this high-efficiency cooling solution is right for you.