Regular paint usually reflects only 80 to 90 percent of sunlight and can’t make surfaces cooler than their surroundings, the ultra-white paint contains barium sulfate, a chemical compound that is used to make photo paper and cosmetics white.
Xiulin Ruan, a professor of mechanical engineering at Purdue, said: “If you were to use this paint to cover a roof area of about 1,000 square feet, we estimate that you could get a cooling power of 10 kilowatts. That’s more powerful than the central air conditioners used by most houses,”
Six years ago is when research on the ultra-white paint began. There have been other attempts from as far back as the 1970s to develop radiative cooling paint as an alternative to air conditioners.
“We found that using barium sulfate, you can theoretically make things really, really reflective, which means that they’re really, really white,” said Xiangyu Li, a researcher on the project.
Lukas Schertel, an expert in light scattering from the University of Cambridge, explained to CNN that if the ultra-white paint was used on a mass scale, such as on generators and other machinery that radiate heat, it “could have a global impact on energy efficiency.”
Furthermore, the researchers believe that the new white paint is the equivalent of the blackest black, Vantablack, which absorbs up to 99.9 percent of visible light.