Evaporative cooling technology has been around forever. When you climb out of a swimming pool on a hot day, the evaporative effect cools you down. In Egypt, servants cooled their Pharaohs by waving giant leaves over water-filled ceramic jars. For the Romans and other ancient Mediterranean cultures, soaked towels and plaza fountains served the same purpose. From then to now, the technology has advanced, though.

Turning to The Past

How did ancient civilizations stay cool? Well, just like birds in flight, nature still has a few tricks up her gossamer sleeves. After all, aircraft engineers are still learning to build better aircraft, and they’re doing so by watching birds and flying insects. In olden days, porous water pots and cool building materials came together to provide a natural, sustainable chill. A step up from those fundamentally effective cooling solutions, Arab nations and Middle Eastern civilizations adapted their architecture. Ancient Stepwells, built in India and beyond, represent a key example of this early technological development.

Humbled by Early Technological Developments

Complex architectural edifices can still be found all over India and other parts of the ancient world. They used cool stone chambers and aqueducts, plus all manner of existing materials to realize elaborate designs. In the 19th century, though, more dynamic components transformed those free-flowing solutions into something far more active. Water pumps sent sprays of fluid through ducts, which also used powered fans to cool textile mills and other temperature-sensitive commodities. From here, wet blankets and pedal-powered fans gave way to true direct evaporative cooling technology.

Early Evaporative Coolers

Picture the scene. Coastal cities are established, and people are taking up residence in desert areas. The evaporative cooler arrives as a necessity, as a product that’s made of wooden panels and metal mesh. Burlap cloths come first, then there’s the early Twentieth-century electric fans and water pumps, which supply water to shredded wooden pads and burlap. The water evaporating principles operate just like they do today, by entering the hot air and acting as a constant source of enthalpy. Since then, all kinds of wet bulb and relative humidity graphs have come on the scene as appliance-refining aids, but the underlying principle still remains very much the same.

At one end of the bookending time zones, porous pots and handheld palm fronds did all the work. At the other end, where we are today, super-efficient portable appliances carry out the same duties. And the developments are still popping up, to this day. Diminishing the environmental impact, as imposed by air conditioning systems, evaporative cooling technology is advancing, so much so that the sustainable homes of tomorrow may well all use this water evaporating effect.