Earlier quoted context omitted.
1) Depends where you live. In a lot of the world's biggest cities in terms of population you've got to travel really far to find land. Probably still cheaper to transport the goods into town than grow it locally, but that comes at the expense of freshness, time, and taxing a freight network that could be used to transport other things. Not to mention places like the Vatican, Singapore, Hong Kong, etc, which don't rea…
To address your point two : a crystalline Si PV panel has 25% efficiency, and the best white leds are about 45% efficiency. So the sunlight->panel->led->light conversion does waste ~90% of the sunlight. This is made less bad by not lighting plants with white light but purple light, but clearly solar panel on the roof, plants indoor don't make much sense. Now, the reasoning is completely different if the electricity i…
Why not? Wasting 90% of the sunlight is still better than using sunlight directly, where the plants themselves only use 4-7% of the sunlight. The plants are wasting all the green-spectrum light, which is where most of the sun's energy is.
Besides, you wouldn't use white LEDs, there's no sense in that. You'd use LEDs tuned for the wavelengths that plants actually use.