Tuned radiative cooling for PV solar panels?!

[DanKegel]

OK, I think I get it now.

Roofing materials are rated for solar reflectance and thermal emissivity.
That latter number just means how well it radiates heat.
eg gold and some other metals have low emissivity, hence films of them can be used as radiant barriers.

Ideally you want the solar panel's cover to efficiently radiate heat.
As the paper mentions, glass does already; they're just trying to improve on that a bit.

See also this book about spacecraft power

https://books.google.com/books?id=fV7y6lPL5RgC&pg=PA312&lpg=PA312&dq=ir+emissivity+solar+cells&source=bl&ots=SR17F4glOD&sig=1U38NtpHuXCJFKawTDA4HaYKC3U&hl=en&sa=X&ved=0CDMQ6AEwBWoVChMIjbDj8biXyAIVAjuICh1lfQjh#v=onepage&q=ir%20emissivity%20solar%20cells&f=false

The references to the cold of space still sound kind of silly, though.

[SunEagle]

More details at
https://www.osapublishing.org/optica...1-32&id=296235

Definitely more details.

They still need to figure out how to either block the wavelengths that generate heat or a way of quickly radiating the heat that is collected.

I am still not sure what they propose will work under all sunlight conditions or what the cost would be for each solar panel.

Still trying to eliminate heat which is a detractor of pv cell efficiency is a step in the right direction.

[DanKegel]

More details at

https://www.osapublishing.org/optica/fulltext.cfm?uri=optica-1-1-32&id=296235

[SunEagle]

This is a bit science-fictiony, and I don't understand it, but:

http://engineering.stanford.edu/news/stanford-engineers-invent-transparent-coating-cools-solar-cells-boost-efficiency

http://www.pnas.org/content/early/2015/09/15/1509453112

Supposedly there's a transparent material the prefers to radiate heat at a wavelength that passes through air without heating it.
Putting a layer of that on a solar panel lets the panel radiate heat away more efficiently.
Or so they claim.

Any physicists in the house? Can someone explain how that would work?

I read a similar article about Stanford. Seems pretty much sci-fi. Although stranger things can be true.

It is just hard for me to believe someone found a material that is clear enough to pass the spectrum of light that a pv cells like yet reflect the longer IR waves.

[DanKegel]

This is a bit science-fictiony, and I don't understand it, but:

http://engineering.stanford.edu/news/stanford-engineers-invent-transparent-coating-cools-solar-cells-boost-efficiency

http://www.pnas.org/content/early/2015/09/15/1509453112

Supposedly there's a transparent material the prefers to radiate heat at a wavelength that passes through air without heating it.
Putting a layer of that on a solar panel lets the panel radiate heat away more efficiently.
Or so they claim.

Any physicists in the house? Can someone explain how that would work?