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Comment by Yaa101 | Hacker News Reader

Interesting, apart from more efficient solar panels it could hand us a solution to better protect our skins with colored sunblock.

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I'm not sure the same consideration applies to sunblock. The article makes the case that plants always "want" to let through the same quantity of light, but not necessarily the same proportion, while we ideally want to block 100% of UV all the time.

I think this might be a good place to add this reminder:

"Vitamin D is made when UV (more precisely, UVB rays) react with a compound (7-dehydrocholesterol) in the skin. The best rays for UV synthesis have wavelengths between 270–300 nm." [1]

[1] https://www.sciencelearn.org.nz/resources/1313-vitamin-d-and...

270nm is UVC territory. Did you mean 280nm instead?

That is a fair question. This is what I find. [1]

Ultraviolet B UV‑B 280–315

Ultraviolet C UV‑C 100–280

[1] https://en.wikipedia.org/wiki/Ultraviolet

My read is "UVB" is the popular medicine way of saying UV is needed for the body to synthesize vitamin D. It was not considered necessary to point out part of the useful spectrum is in "UVC" territory.

Also kills microbes on surfaces.

Solar panels are already much, much more efficient than photosynthesis.

That doesn't preclude that further optimisation of solar panels could stem from research on photosynthesis.

Perhaps.. but part of the reason plants "lack efficiency" compared to our solid state electronics is that they need respiration to exchange input and output products with the environment and the entire plant needs to be laid out in such a way that it can maintain a root structure while being advantaged with respect to competing vegetation.

The two problem spaces are similar in that they use light, but exceptionally different in almost every other respect.

Also, sunburn is a real problem (aka excessive sun) without enough water or other nutrients for them.

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