Researchers at Purdue University have developed a paint that's significantly whiter than the whitest paint currently available. Tests on their “ultra-white” paint showed that it reflects more than 98% of sunlight. That suggests that it could help save energy and fight climate change. Commercially available white paints reflect between 80% and 90% of sunlight. Every 1% of reflectance translates to 10 watts per meter squared less heat from the sun. So, if you were to use the ultra-white paint to cover a roof area of about 1,000 sq ft, it’s estimated that you would get a cooling power of 10 kilowatts. That's more powerful than the central air conditioners used by most houses. Cool white roofs are seen as an easy climate solution because they can reduce energy demands and create lower ambient temperatures. The new paint contains a compound called barium sulfate, which is also used to make photo paper and cosmetics. Researchers are now working with a company to produce and sell their paint, which they say should be similar in cost to currently available paints.
