My understanding was that you put the solar in the desert, so that you can put the vertical farm somewhere else where soil, water, transport logistics is easier.
So the question is whether a greenhouse/farm in the desert is easier than solar in the desert connected through grid to vertical farm somewhere else.
I have no data. My guess is the ongoing logistics of piping electricity out of the desert is easier than fertiliser into the desert and produce out to where people live.
Hmmm, that’s a good question, I couldn’t find much information publicly available and I can of course not disclose internal. But there’s a little in this annual report from 2015. There’s an rudimentary illustration on the second page. Unfortunately it doesn’t include many of the details which I found most impressive, we had just started the project in 2015, so that might be why.
I'm also just an armchair intellectual speculating here...
Not "per se" a knock against greenhouses, but definitely one of the things you're looking for is a closed system rather than the sort of greenhouse you'd get in many places in America, where it's just a robust plastic tent-on-a-concrete-slab, and they don't care much if the water runs off. In a desert you'd be really concerned about making sure the whole works has very, very low water-losses.
The key thing to make this useful is to conceptualize it not as the sort of area, like the Nile, where they've already got an ample water supply. To make this useful, it's best to think of something where there's basically no water supply at all, and we're trying to crack the problem of "okay, how could we grow crops here?" Something that right now, is just bone-dry barren desert. Most of the solutions we rely on in the wetter world just don't really care much about water loss.
Something that could fit the definition of a greenhouse, with windowed ceilings, might well be a viable solution. But I do suspect there's some correlation between making a grow site more bunker-like and lowering water loss (especially if it's recessed into the earth).
The other huge upside of a truly sealed system is it's another approach to pest control. Sealing the system could potentially completely eliminate the need for pesticides and herbicides. Right now those have huge negative externalities.
Some type of semi-reflective coating to keep heat low and closed loop systems? I wonder how expensive and actually complex would it be to find nano-scale substance that would reflect most of wasted light spectrum while allowing the one needed...
