Unlike traditional paint, the “ultra white” paint is made with a chemical compound called barium sulfate, which is also used in the production of cosmetics and photo paper.
The barium sulfate particles are made of different sizes, which “scatter” the sun’s rays and can even cool immediate surrounding surfaces.
White paint has been used in warmer climates for centuries to cool buildings from the heat, but this new formula absorbs much less sunlight and therefore heat, the researchers said.
An image from an infrared camera shows how a swatch of the new ultra-white paint cools the environment. The image on the left shows the paint in place, while the image on the right shows how it cools the environment using special technology. The darker the color, the lower the temperature. Credit: Purdue University / Joseph Peoples
While regular paint absorbs between 10% and 20% of the sunlight, the new paint absorbs only 1.9% – an amount small enough for a building to lose heat in general, they said.
“If you used this paint to cover a roof area of about 1,000 square feet, we estimate that you could get a cooling capacity of 10 kilowatts. That’s more powerful than the central air conditioners used by most homes,” said lead investigator Xiulin. Ruan, professor of mechanical engineering at Purdue
It’s the “coolest ever,” they claimed, capable of keeping surfaces 19 degrees Fahrenheit cooler than other environmental environments at night, and 8 degrees Fahrenheit lower during bright sunlight.
Lukas Schertel, a light scattering expert from the University of Cambridge who was not involved in the study, told CNN the findings were potentially exciting and that the paint, if used on an industrial scale, could positively impact the climate. by reducing energy consumption.
He said that research on cooling paints has gained momentum in recent years and that if they were applied on an industrial scale, including to generators and other machines that radiate heat, they could theoretically “ have a global impact on energy efficiency. to have’.
The challenge would be to encourage commercial adoption, he said – and to do that, the production of the paint would have to be scalable and affordable.
The materials used in the formula are already “relatively widely available,” he added, but a manufacturer should “make it cost-effective.”