Solar Evaporative Coolers

Evaporative cooling uses a system of air flow called the Fresh Air System. In this system, fresh outside air is brought in through the cooler, where it is cooled and pushed through the building, then exhausted to the outside through screened windows or doors.

Swamp coolers are relatively simple appliances, and we've all experienced the power of evaporative cooling at one point or another. The evaporative cooling principle can be likened to putting on a wet t-shirt and standing in front of a fan. If the climate is dry and the humidity is low, the cooling (and sometimes even chilling) effect will be instantaneous. On the other hand, in areas with high humidity levels, this process will only result in dampness on the skin and in the air. In addition, unlike air conditioners where you will need to close all doors and windows, an evaporative cooler will require adequate air flow and ventilation in order to evenly and effectively distribute the cool air through the home and expel warm, moist air through window openings.

There are typically two types of swamp coolers: direct and indirect. Direct evaporative cooling lowers the ambient temperature by changing water to vapor, and warm, dry air is transformed to cool, moist air, while indirect evaporative cooling involves some type of heat exchanger.

Typically, swamp coolers used in residential or industrial settings utilize direct evaporation, and this usually involves an enclosed plastic or metal box with vented sides and a centrifugal fan, along with an electric motor and a water pump to moisten the evaporative cooling pads. These types of swamp coolers can include casters for portability, be mounted on the roof, or placed by the exterior walls or windows of a building.

In order to cool, the swamp cooler's fan draws warm air through the unit's side vents and through the damp pads. Subsequently, air evaporates the water from the pads, and these are constantly re-dampened in order to continue the cooling process. These cooling pads can be constructed of materials such as excelsior, plastic, or melamine paper, and the pad's thickness plays a great part in a swamp cooler's cooling efficiency because of the increased surface area.

In addition to being able to providing reliable and cost-effecting cooling for homes, swamp coolers are also perfect for industrial and commercial applications such as automotive garages, warehouses, and agricultural areas. As well, because swamp coolers use very little electricity and have a large cooling area, they are also suitable for outdoor use, such as athletic fields, concerts, and stadium. Swamp and evaporative coolers can be stationary or mobile.