A Hairy Solution to Cool the Planet | Sumitra Rajagopalan | TEDxCoriano

Quick Overview

Sumitra Rajagopalan presents a cheap, energy-free cooling technology inspired by nature's radiative cooling, specifically camel hair, which reflects heat and pulls body heat away, achieving a remarkable 250C temperature difference in laboratory tests using spray-applied materials costing less than a dollar per application.

Key Points: Extreme heat stress is causing crises globally, exemplified by New Delhi reaching 500C, heat-related deaths among workers building the Qatar FIFA stadium, and London declaring a national emergency. Nature utilizes 'hair' for cooling in organisms like the camel, cactus, and desert scorpion through a process called radiative cooling, which reflects heat and pulls heat away from the body into outer space. Scientists worldwide replicated this effect using fine fibers, achieving temperature differences between 100C and 150C in deployments in Phoenix, Hong Kong, and India. Rajagopalan and colleagues achieved a significant 250C difference when testing their sprayed material in an oven set at 550C, demonstrating effective heat mitigation. The experiment involved dissolving their material and spraying it like graffiti, eventually replicating the fine hair structure seen on camels and cacti. The experimental material application cost less than a dollar, with the spray can costing an additional dollar, making it an extremely cheap and deployable solution. While the ultimate solution to climate change remains transitioning from fossil fuels to renewables, this cheap technology can immediately deploy across continents to save lives compromised by heat stress.

Context: The presentation by Sumitra Rajagopalan addresses the escalating global problem of extreme heat stress, citing examples from New Delhi, Qatar, Greece, London, and Phoenix, where high temperatures are making life unbearable and causing severe health issues like kidney disease in young workers. Rajagopalan pivots from the problem to an innovative, nature-inspired solution, focusing on how organisms like camels survive extreme heat, leading into the scientific exploration of radiative cooling.