Hand wavy arguments as to why this is a bad idea are ... well, just hand wavy. << Solar is ~20% efficient LED's are less than ~40% efficient so you would need

Hand wavy arguments as to why this is a bad idea are ... well, just hand wavy. << Solar is ~20% efficient LED's are less than ~40% efficient so you would need more land area for solar farms than you save by growing indoors. On top of that you need to pay for all your capital costs. There are other issues, but if this was close to cost effective you would be seeing this in Iceland which gets little sunlight in the winter and has cheap energy costs. Instead they use suplimental lighting inside green houses to boost production. >> I thought the vertical stacking makes more efficient use of the light than the single layer you find in a farm or green house. It means that even though the light is produced inefficiently the vertical stacking is intended to cancel out that inefficiency by using the light more efficiently. Moreover, the optimization of the plant's exposure to light through automated means adds to increased efficiency in the plant's use of the light. If every grower did this, it would (or could) destroy Monsanto's business model. I love it.