A blast from a heat gun has turned most of the black tile in this image white. The prototype tile, developed by recent MIT graduates, is designed to turn dark in cold weather and white in warm weather. Credit: Patrick Gillooly
From Live Science:
On a blazing summer day, a black roof gets miserably hot, while a white roof reflects the sun and keeps a home cooler. In winter, the warmth generated by a solar-radiation-absorbing black roof can save energy.
That's well-known and simple enough. Unfortunately, you can't have it both ways. Well ...
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