A white, paint-like coating that reflects more than 95% of sunlight and sends heat out through the sky. Born in a City University of Hong Kong lab, it has been used on more than 500 projects in about 30 countries, from Hong Kong towers to grain silos and shipping containers.
A two-person company fills weather balloons with sulphur dioxide, lets them burst in the stratosphere and sells the result as "Cooling Credits". It is the most controversial product in this series: tiny in physical scale, but a direct test of who gets to decide whether humans dim the sun.
Small pumps lift seawater from under the winter ice and spread it on top, where it freezes fast. The goal is thicker, brighter ice that survives longer into summer and keeps reflecting sunlight. It is one of the most watched, and most criticised, sunlight reflection experiments in the world.
A thin film and fabric that reflect almost all sunlight and radiate heat out through the sky, staying cooler than the surrounding air even at noon. It wrapped an entire pavilion at Expo 2025 in Osaka and is now marketed in Europe by a Munich subsidiary.
A roof coating developed at IIT Bombay and sold by a small New Delhi company, designed to bounce back the near-infrared part of sunlight that heats concrete and tin roofs. As Indian states start to require cool roofs, products like this are moving from pilot projects to building permits.
