Evaporative cooling works with two simple natural processes, water evaporation, and air movement. Evaporative cooling systems, sometimes called “swamp coolers” because of the amount of water they use, can effectively lower the temperature as much as 30 degrees Fahrenheit. These systems have been around for a long time but have been making somewhat of a comeback because they use approximately 75% less energy consumption than a typical air conditioner. Where they would be used most, hot sunny regions, they can also be outfitted with solar panels to run the fan and water pump that would lower energy costs even more or even eliminate them altogether.
These systems are very easy to design and run. They can be placed in a window or used as a system to cool an entire house. The system uses large pads that are continuously kept wet by a water pump; this pump drips the water at the top of the pad and gravity forces the water down through the pad. A large fan draws hot, dry air through the wet pads which evaporates the water and cools the air by a range of 30 degrees. Thus, much cooler air is then blown by the fan throughout the house.
These systems are much easier to operate than conventional air conditioning and cost only about half as much for a system of the same size and cooling ability. The only down side to this type of cooling system is that it must be used in an area with low humidity. This is required because for the evaporation process to work efficiently, the outside air cannot contain a large amount of water, or the cooling process will not work as well.
For this reason the best places to use this type of cooling system are in southern states of Australia, Victoria, South Australia etc., anywhere that is hot, dry, and the sun shines all day. In fact, this system works especially well during the hottest time of day since that tends to be when the temperature is the highest and the humidity the lowest. It also is when the sun is shinning the brightest which would be perfect if you were to run the system using solar power. Since these coolers use 75% less electricity than regular air conditioners, you would be saving approximately $150 per year on energy. In the hotter dessert climates and if you used solar energy, you would save even more.
Another nice feature of evaporative cooling is that you are taking outside air, cooling it and then blowing it into the house. This circulates fresh air throughout your home and even does a complete air change every one to three minutes. At least one window should be left open to let the cooler moist air force out all the hot, dry air from the house. This moist air helps keep your wood furniture and fabrics from drying out and also traps dust and pollen in the evaporation pads. Pads should be replenished every year or two and only cost around $20 – 40 for a set of two.
If you live an a hot, dry, sunny region, you should take a look at the many benefits and huge energy savings you can gain from installing an evaporative cooling unit over the costly and much less energy efficient air conditioner. This is certainly a win for the average home owner and a win for the environment since so much less energy is being consumed.Read More