What are the possibilities for this in areas that are far too hot/dry for crops? Underground growing retains water and can be more easily temperature controlle

What are the possibilities for this in areas that are far too hot/dry for crops? Underground growing retains water and can be more easily temperature controlled. Given that photosynthesis does not use the full spectrum, how efficient do LEDs and solar panels have to be before you have a net gain on solar energy converted into photosynthesis?