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A comment on Is air conditioning making cities hotter?. Parent comment

Re:Is air conditioning making cities hotter? by chris_va on Sunday September 10, 2023 @04:15PM (#37459574)
They are usually reflective out of band, for unifacial (ito on semiconductor on a metallic backing), so ~40% of the radiation is heading back to space, vs 10-20% for a typical roof.

However... that means they don't radiate well at night (they have low emissivity and are not well thermally coupled to the roof). Painting the roof white is ideal.

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Re:Is air conditioning making cities hotter? by pfdietz on Sunday September 10, 2023 @06:09PM (#37460612)
Hmm. I wonder if the glass can have a coating that would make them more emissive in the atmospheric transparent bands of the mid- and far-IR.
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Re:Is air conditioning making cities hotter? by jstanley on Sunday September 10, 2023 @11:26PM (#37462519)
It is easy to tell that they are black in the visible spectrum because they look black.
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