If we do that it would nice to have some experience ready to go on the Industrial farming side.

Also it takes protons to haul the wheat to market, to harvest it, til the soil and plant it. Not to mention all the externalized costs of large scale outdoor agriculture.

Also on mars and the moon beckon, having a closed loop there would likely dwarf anything we can grow on a field here because of the energy costs of moving tons of food into space.

"However, given the high energy costs for artificial lighting and capital costs, it is unlikely to be economically competitive with current market prices."

There is a limited amount of sunlight hitting an area. That means to scale crop yields by going vertical, you need artificial light.

At the moment energy is not harvested in a (sustainably) scalable manner, so vertical farming is infeasible except to boost local production in rich countries.

Saying it's a "pipe dream" is a bit too harsh imo, I think as energy demand ramps up, and oil keeps going down eventually we will be forced to produce unlimited amounts of cheap energy through nuclear power plants, but that's just my vision for the future..

2. I’ve heard the real efficiency is tailoring light from high efficiency leds per plant.