Ancient Evaporative Cooling Returns as a Low-Cost Alternative to AC
Evaporative, or “swamp,” coolers—originally refined in Arizona in 1908—still provide affordable cooling in dry U.S. regions despite the spread of modern air-conditioning.
Centuries-old cooling methods that relied on air flowing over water were adapted into the modern evaporative cooler by Oscar Palmer in Arizona in 1908. The system draws hot outdoor air through water-saturated pads, causing evaporation that cools and humidifies the airflow before it enters a building. Widespread adoption in the 1930s brought relief to arid states like New Mexico and Nevada, and the devices continue to serve many households lacking central air-conditioning.
Advocates such as Eric Verpolegen, founder of the nonprofit CoolVeg, and Ankit Kalanki, principal of cooling at the clean-energy NGO RMI, highlight the units’ low cost and modest power draw, especially in dry climates. They also point out that rising humidity in some areas limits performance, spurring development of hybrid technologies that separate moisture control from cooling. The enduring relevance of swamp coolers underscores the link between rising temperatures, energy demand, and greenhouse-gas emissions.
Why it matters
Swamp coolers offer a cheap, low-energy way to stay cool in dry regions, reducing reliance on power-hungry air conditioners.
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