Imagine a future where houses are painted with a specific paint that reflects virtually all of the sunlight, keeping your house cooler and thus requiring less electricity -- massively better for the environment.
Purdue University researchers have created an ultra-white paint that is not just the whitest paint ever made, but this new paint could eventually reduce or even remove the requirement for having an air conditioner. The researchers began their journey looking to reflect sunlight away from buildings, but it has turned out so good that the team made it into the Guinness World Records.
The new white paint reflects 98.1% of solar radiation, while it also emits infrared heat -- thanks to it absorbing less heat from the sun that it emits -- the surface of anything that this paint covers would be cooler below the surrounding temperature, without using power. This is quite the reverse of an AC unit and even regular commercial white paints.
A commercial white paint, when heated by the sun, gets warmer... not cooler -- whereas this new ultra-white paint does the opposite. There are paints available that are designed to reject heat, but it only hits 80-90% and it doesn't make surfaces cooler -- so this new paint is quite the creation.
Purdue University professor of mechanical engineering, Xiulin Ruan, said: "When we started this project about seven years ago, we had saving energy and fighting climate change in mind".
How was the paint created? The researchers used a very high concentration of a chemical compound called barium sulfate, as well as different particle sizes of barium sulfate in the paint. Barium sulfate is also used in photo paper and cosmetics, but is looking like it could be the key ingredient in the future paint on buildings and homes.