I want to build a 21st century farm. I’ll start with a solar array and a wind generator (probably a chimney). I’ll store energy in a liquid storage facility using a redox flow battery. Then using the storage cell I’ll run a CO2 extractor and maybe a water purifier.
Then I’ll build a sealed building similar to the PlantLab system. I’ll use red and blue LED’s on for 20 hours per day (or whatever is the optimum day/night cycle for the specific food I’m growing), high concentrations of CO2, and optimum temperature/humidity to grow food dramatically faster than a traditional farm.
There are very few consumables needed, some fertilizer and seeds. It’s not clear to me how long a wind generator or solar array can last. I’m sure eventually something will be needed for repair or maintenence.
Depending on the outdoor temperature this system could work for decades. If the greenhouse were buried in 57F degree ground and well insulated it may not lose much heat to the ground.