I understand about the rooftops but we have to consider ALL available space to determine the boundaries of the system, what works what doesn’t. A goal is to same what kind of adaptable,economical,insulated growth area can we place where and what will it’s probable output capabilities be. That’s the one of the points of getting reliable telemetary from a small space ( farm computer) then seeing what it takes to scale it up to larger spaces, what materials do what, how does the growth medium work under different temps, water quality,even pressure ( coffee tastes better grown at altitude ) etc. Once you have some idea of the effects on an area you can find which bill of materials will be suit your budget and goals. Right now we have people growing lettuce out of gallon milk jugs with a cheap T5 light from home depot. The goal here is to get people thinking about this in offices ( yep they are growing there as well), school etc. It’s a system called Kratky ( see videos above) and is low maintenance.
Solar energy is market driven so the day it becomes economical to use it will be the day you see it grow like a weed, low oil prices ( and probably staying low for some time) aren’t going to help it’s case, ho hum… As to the conference, please try and attend there are some excellent speakers and Dr Nate Storey seems to have some interesting ideas, that may bear on your apartment space issue. He grows UP not sideways using grow towers, you could make one yourself ( just an example ) https://www.youtube.com/watch?v=663kBnFLBBM&list=PLbiYoiwgZY248_LGpNI872VHAWmZPxHm6