It doesn't actually take that much juice these days. On top of being able to use solar and wind generated power we also have leds that barely use any electricity to run.

Aside from the initial investment for the setup, the ongoing energy and resources needed for hydro and aero are most definitely going to be less than dirt farming especially when you factor in being able to grow year round. And don't forget the reduced amount of fertilizer and water usage. The water isn't lost to the ground with only a small amount of it being used by the plants.

Basically this is like ev versus ice. When you don't factor in everything, one looks better than the other but with all things considered, ev is way better than ice.