- #1
shane2
- 89
- 3
I'd read that "Most solar energy has a wavelength close to 0.5 µm" and that
"All surfaces radiate heat, mostly at wavelengths close to 10 µm wavelength."
So, just to confirm, that means that a black roof in the clear summer sun is heating up primarily as a result of the wavelengths as seen under most of the red above and later whatever that hot roof is re-radiating away that night will be in wavelengths mostly under the blue, correct?
OK, so here's my question, does common radiant barrier, like the aluminum foil faced rolls you see for sale that claim a 95% reflectance, do they equally reflect radiant heat at both 0.5 µm and 10 µm wavelengths? If not, how significantly so do they not?
If RB does not reflect both equally, I'll have a follow up question.
Thank you for any responses.
"All surfaces radiate heat, mostly at wavelengths close to 10 µm wavelength."
So, just to confirm, that means that a black roof in the clear summer sun is heating up primarily as a result of the wavelengths as seen under most of the red above and later whatever that hot roof is re-radiating away that night will be in wavelengths mostly under the blue, correct?
OK, so here's my question, does common radiant barrier, like the aluminum foil faced rolls you see for sale that claim a 95% reflectance, do they equally reflect radiant heat at both 0.5 µm and 10 µm wavelengths? If not, how significantly so do they not?
If RB does not reflect both equally, I'll have a follow up question.
Thank you for any responses.