The “whitest” paint in history reflects 98% of the sun’s rays

Scientists in the United States have developed paints that are “much whiter than the whitest paints currently available.”

Tests conducted by Purdue University researchers with “ultra-white” paint have shown that more than 98% of the sun is reflected.

It saves energy and helps fight climate change, scientists say.

Painting a “cool roof” white is an energy-saving approach already deployed in some major cities.

According to Professor Xiulin Ruan, Purdue’s senior researcher in West Lafayette, Indiana, commercially available white paints reflect 80% to 90% of the sun’s rays. “This is a big problem because for every 1% reflectance, there is 10 watts per square meter and less heat from the sun,” he explained.

People in West New York, New Jersey are watching the sunset over New York on August 23, 2015.

New York City Adopts “Cool Roof” as a Climate Solution

“Therefore, it is estimated that using our paint to cover a roof area of ​​about 1,000 square feet (93 square meters) will provide a cooling capacity of 10 kW. This is used in most homes. It’s more powerful than a central air conditioner. “He said.

Can white paint help fight climate change?

“Cool” white roofs are considered a simple urban climate solution.

In the United States, New York recently painted white roofs over 10 million square feet. California has already updated its building code to promote cool roofs. ..

While their benefits are still under investigation, research has shown that they can reduce energy demand and lower ambient temperatures. This has the following additional benefits: Reduce the amount of water used to irrigate cities..

“We did a very rough calculation,” said Professor Ruan. “And we estimate that only 1% of the Earth’s surface needs to be painted with this paint. Perhaps it’s a rock-covered, uninhabited area that could help combat climate change trends. There is. “

How did this paint become “super white”?

The new paint contains a compound called barium sulphate, which is also used in the manufacture of photo paper and cosmetics.

“We used very high concentrations of compound particles,” explained Professor Ruan. “And because sunlight has different colors depending on the wavelength, we use a lot of particles of different sizes.”

The amount of light that each particle scatters depends on its size. “Therefore, we intentionally used different particle sizes to scatter each wavelength.”

Can anyone buy this paint?

Researchers are currently working with the company to manufacture and sell paints. They say this should cost the same as the paints currently available.

“I have already received an inquiry from the museum that we would like to display our whitest white paint side by side with the blackest black,” said Professor Luang.

The ultra black coating is a materials scientist called Vantablack, which was developed in 2014.

Its potential use is almost the opposite of “ultra-white” paints, as it absorbs almost all light. For example, Vantablack, used in space telescopes, can absorb stray light that can interfere with its ability to measure light from objects in deep space.

However, Vantablack, a nanoscale carbon tube coating, is not available to everyone. The invention caused artistic controversy when sculptor and former Turner Prize-winning artist Anish Kapoor purchased the exclusive right to its “use as artistic material.”

In response, UK-based artist Stuart Semple created a pigment that he claims to be the “most pink pink” in the world, and on his website “all but Anish Kapoor.” Made available for purchase for “people”.

A company called Vantablack developer Sally Nanosystems said the exclusive deal with Mr. Kapoor did not eliminate the whitest white that appears with the blackest black in the museum. “It’s not art. It would be seen as an educational exhibition for those interested in science and technology behind extreme light and darkness,” the company told BBC News.

Professor Luang added that it was up to the company to produce “ultra-white” paint, but hoped it would be available to everyone.

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