No, a swamp cooler isn’t a rum-based Mardi Gras libation served in a garish plastic to-go cup in the shape of an alligator (although that does sound tasty right about now).

A swamp cooler, formally known as evaporative cooler, is an energy-efficient alternative to central air conditioning and window units in areas with relatively low or no humidity. They come in all shapes and sizes: portable floor units, windows units, or wall units. Climate is key to operating a swamp cooler — if you’re suffering through a sultry Florida summer, don’t bother with one. It will make the air more humid. But if you live in the arid southwest, a swamp cooler in the home will save you significant money while bringing chilly relief. How cool is that?

In addition to requiring less juice to operate — according to the California Energy Commission, up to 75 percent less energy is needed than with refrigerated units — swamp coolers work by way of simple science: a fan + moistened evaporative cooling pads made from wood or cellulose = air-cooling evaporation. This is a significantly more earth-friendly air cooling/circulation process than refrigeration where ozone-depleting gases like chlorofluorocarbons and hydro-chlorofluorocarbons are involved.

Also, the cooling pads in swamp coolers can double as highly effective air purifiers if well maintained. But take heed: swamp coolers do indeed require water, sometime multiple gallons of it a day, to run smoothly. If you live in a draught-prone area or are more keen on saving water over energy, take this into consideration. 

Below are a few particularly energy-efficient and air-cleansing portable swamp coolers for under $200. 

Waterless Air Cooler Plus @ Air Cooler Plus ($189)

NewAir AF-330 Portable Evaporative Swamp Cooler with Built-In Air Purifier @ Air & Water ($99)

Fujitronic FH-776 Evaporative Swamp Cooler with Fan and Air Purifier @ Amazon.com ($109.95)

Evaporative Air Cooler  - Blue (SF-613) @ Target ($104.99)

Matt Hickman ( @mattyhick ) reports on design, architecture and the intersection between the natural world and the built environment.