
Newly discovered formula explains efficiency gains from bifacial solar cells - known
https://www.purdue.edu/newsroom/releases/2019/Q4/solar-power-from-the-dark-side-unlocked-by-a-new-formula.html
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ncmncm
We need a variety of cell that is transparent to wavelengths plants use, so
they could be used above farmland and pasturage. Many plants could probably be
grown under them in places where it would otherwise be too hot, maybe even
needing less water.

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inetknght
I imagine different plants need multiple different wavelengths.

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ncmncm
Most of the plants I know about are green, and rely on chlorophyll
electrochemistry.

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m-p-3
Don't they look green because they reflect most green wavelengths?

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ncmncm
Yes, they don't use green. Or infrared, beyond 700nm. I don't know if they
reflect the IR like they do the green.

Conversion efficiency of the part they do use can't be more than a few
percent, so they probably radiate in IR. Converting IR radiating from plants,
as suggested in TFA, thus seems like a good idea.

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Havoc
Surely a small stepper motor will still consistently win?

I mean this is cool for fixed structures but overall finding some empty space
and pointing the thing straight at the sun seems better.

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biofrack
Sun trackers are marginally more efficient, but the complexity of motors and a
moving frame make it less desirable.

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clairity
looks like there are (led?) lights under the pictured double-sided gas station
solar panel canopy. letting some of the light through would be more efficient
that the conversion to electricity and then back to light.

and yes, you'd still need lighting at night, but a semi-transparent roof
combined with the wider area lights already in use at gas stations would still
likely be more efficient.

(of course this doesn't consider the value of the shade on hot days)

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klyrs
Woof, what a title. FTFA:

> The formula shows that the efficiency gain of bifacial solar cells increases
> with light reflected from a surface.

Perhaps a better title would be "Newly discovered formula explains efficiency
gains from bifacial solar cells"

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dang
Done. Thanks!

