This Ancient Technology Is Helping Millions Stay Cool
Cheap, low-energy evaporative cooling devices are keeping water, food, people, and even whole buildings cool across India.
by NADEEM SARWAR & SHREYA FOTEDAR
This summer, India has endured possibly its worst ever heatwave. The capital, Delhi, logged a record high of 52.9 degrees Celsius (127 degrees Fahrenheit) on May 29, while India’s northern states have baked at sustained temperatures of more than 42 degrees during the daytime. Only now, as the rainy season starts, are temperatures cooling. But in the coming years, things will only get worse.
For many, respite from the relentless heat has come from an improbable source: the earth. Special pots made from clay, when combined with water, can be used to chill drinking water and the surrounding air. They are helping millions of households that don’t have air conditioning and refrigerators stay cool. Companies are also creating earthen building materials that are better at keeping out heat than bricks and mortar, drawing on knowledge that has helped keep people cool for thousands of years.
“We have lost track of traditional systems that have worked for us in the past,” says Monish Siripurapu, the founder of CoolAnt. His company is working to revive these preindustrial cooling techniques at scale, creating clay-based cladding and cooling units that can be installed in both homes and businesses.