more on the paint:
https://www.purdue.edu/newsroom/rele...roundings.html
“It’s very counterintuitive for a surface in direct sunlight to be cooler than the temperature your local weather station reports for that area, but we’ve shown this to be possible,” said Xiulin Ruan
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“An infrared camera gives you a temperature reading just like a thermometer would to judge if someone has a fever. These readings confirmed that our paint has a lower temperature than both its surroundings and the commercial counterpart,” Ruan said.
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Developing this paint formulation wasn’t easy. The six-year study builds on attempts going back to the 1970s to develop radiative cooling paint as a feasible alternative to traditional air conditioners.
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According to the researchers’ cost estimates, this paint would be both cheaper to produce than its commercial alternative and could save about a dollar per day that would have been spent on air conditioning for a one-story house of approximately 1,076 square feet.
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grains of salt of course in terms of the above is Purdue's PR dept so they also can gloss over the science and downsides while hyping benefits