Evaporative cooling has been around much longer than central air conditioning and has proven to be just as good at cooling in arid parts of the country. The technology works by the same process our bodies use to control temperature—perspiration. As we sweat and our perspiration evaporates, our skin feels cooler. Swamp coolers use hot air to absorb water, and the hotter the air, the better the cooling. Warm air from outside is drawn into a fan and pushed through moistened pads. The air is then vented into a room or through ductwork. Pads are made of shaved wood (cedar or aspen) to discourage mold and mildew from forming.
Evaporative cooling systems are inexpensive, efficient, and offer a more natural way of cooling—and they’re making a comeback. They’re popular because they offer a low-cost way to cool a room or a building, they require simple technology, and they also prevent wood from drying out, which is good news for floors and furniture. The downside to evaporative cooling is that they do not work in humid climates and require a constant flow of water.
Evaporative humidifier technology is sound, but there are always developments that are noteworthy. Here are some of the newest developments in swamp coolers:
- There are now two-stage units that cool the air before hitting the cooling pad. They are rated to cool as effectively as A/C, but cost much more than the average swamp cooler. This advance might be worth the initial investment, but the process is more complicated than in standard units.
- Some manufacturers are using photovoltaic panels (solar energy) as an energy source for units. Solar energy can provide enough energy to run a household unit, and even some industrial units. This is good news for homeowners and industries that want to go green.