Conventional agriculture works much better. You can build acres of greenhouses and make a profit.
Vertical farming is such an abject failure that every single vertical farm is biomass constrained, meaning that they have to stretch their biomass with water. This is why vertical farms generally only sell "leafy greens", a marketing term that tries to sweep the inherent technical failure of vertical farming under the rug.
Solar panel captures energy from an 800nm wide range (300-1100nm)
Plant captures energy from a 300nm wide range (400-700nm)
The solar panel could reproject and amplify the 300nm range at (800/300=) 2.7X more power than the sunI’m curious what is physically possible, if we assume we can achieve the max possible efficiency. I’m guessing there’s behavior like a Carnot engine, and the energy transfer can only be up to ~86% efficient (but please correct me if I’m wrong!!). In that case, conversion from light to energy via solar panels -> conversation back to light via leds should be 0.86*0.86 = 73% efficient in best case. And the full effect should be (800/300)*0.73 = 1.94, about twice as good as growing plants with the sun’s direct light. I’m surprised that seems possible!
p.s. My efficiency guesses are probably wrong. Please correct me.
And as you say the LEDs aren't 100% efficient either, though both deep red and bright blue are among the most efficient, about 85% there.
So that leaves you with about 50% overall just from those two.
So that would imply they are inherently more efficient just looking at the figures provided.
When we've got actually braindead policy like ethanol fuel mandates, the ROI of switching a corn farm to solar is so incredibly high that solutions like this just aren't competitive.
I wish some of our billionaire class would turn their attention to these things rather than building yet another rocket company. Maybe that's why Gates is buying up farmland, who knows.