World’s Whitest Paint Could Eliminate Need for Air Conditioning
Will this game-changing new paint really change the way we cool down buildings?
Did you know the color of the paint on the outside of a building can drastically impact the temperature inside? Engineers at Purdue University have developed a paint that is so white it may eliminate the need for air conditioning.
By coating buildings in this ultra-white and highly reflective paint, researchers estimate that they can cool buildings without any mechanical air conditioning units.
“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,” said Xiulin Ruan, a Purdue professor of mechanical engineering. “That’s more powerful than the central air conditioners used by most houses.”
The paint, officially certified by Guinness World Records as the “whitest paint in the world,” has gone through multiple iterations and retoolings. The finished formula uses a chemical compound called barium sulfate, the same one that gives paper and makeup their whiteness. The particles are all different shapes and sizes, adding to their reflectiveness.
Researchers at Purdue demonstrated the cooling powers of this white paint with impressive results. During testing, surfaces covered in the white paint were eight degrees F cooler than their surrounding area when exposed to strong sunlight during noon hours. At night, the paint kept surfaces 19 degrees cooler than their surroundings.
Typical “heat-reflecting” paints on the market reflect 80 to 90 percent of sunlight. Purdue researchers say its ultra-white paint reflects up to 98.1 percent. While it is technically possible to make the paint even whiter, researchers worry that doing so would compromise the integrity of the paint.
“Although a higher particle concentration is better for making something white, you can’t increase the concentration too much,” said Xiangyu Li, a postdoctoral researcher at the Massachusetts Institute of Technology who worked on this project as a Purdue doctoral student. “The higher the concentration, the easier it is for the paint to break or peel off.”
So when will this paint find its way into the hands of the public? It might be sooner than you think. According to a news release, Purdue has filed patent applications for the paint formula and is working with an unidentified company to scale up the production and get it on the market.