I came across an interesting article which basically mercilessly beats up on the Vertical Farm concept.
Assuming you have'nt clicked on either of these links , here is my quick rundown. If you have(my , it must be a slow work day huh?), than skip past this paragraph.
Vertical Farm concept presented as it is , makes a compelling argument about how Man needs to learn how to grow crops indoors , and closer to where they will be consumed, despite such superflous points such as the one about how this could be integrated into refugee camps. However , it does have some major flaws as ably pointed out by the Monbiot article. Some glaring ones are
1. How the plants are supposed to get light.
2. How this whole venture would make sense at the current urban land rates.
3. Other fanciful claims about how Vertical Farming would not need fertilizers or pesticides.
There are more reffer Monbiot's article.
Not for a minute am I trying to defend Dickson Despommier, but I don't think his idea can be dismissed of hand just because its missing so many important details. A lot of problems need to be resolved by minds far more brilliant than Despommier, before his concept can become reality.
Clearly such a farm only makes sense for crops that have a limited shelf life which would mean primarily frutis and vegetables. Wheat and Rice can be stored for long periods and it hardly makes sense to grow them in controlled environments close to where they will be consumed.
Though a Vertical Farm in Midtown Manhattan will never be a good idea, one on the outskirts of a less expensive city might be worth exploring.
There are a couple of ideas I can think of to make sure multiple floors recieve natural light simultaneously.
1. A series of lenses concentrate light from floor to floor, in addition to the light coming in from the glass walls.
2. The floors can be designed as non-overlapping triangles or some other geometrical shape so light makes its way to multiple floors simultaeously.
3. If there is a provision to rotate these floors , parts which might not have light earlier can be exposed per a fixed scedule.
All this falls in the category of spitballing I admit, and need to be researched.
Finally , the vertical farm idea if it ever achieve frutition, will be because the economics warrant it, which means, when 2050 comes, and we have no way to feed our vast populations, vertical farms might not seem like such an expensive and wasteful proposition(though I doubt , we will see one in Midtown Manhattan)