total power requirement of the united states / amount of average power including weather and TOD produced by a square meter of land + amount of land to store necessary batteries = a corner notched out of nevada. not multiple states. i dont think you need a phd to see this, and elon musk also agrees with this and i think he is knowledgeable enough about solar and batteries. plus, there are lots of efficiency gains still in the pipes that will reduce our power consumption. when all houses are properly insulated, heated with a heat pump, have efficient appliances, thermal loops and have solar on their roofs then all of this becomes even more feasible. and thats not even including wind, hydro or thermal.
* https://environmenthalfcentury.princeton.edu/experts
I'm just copying and pasting the December 2020 report.
Off the top of my head, renewables (in the US) only produce electricity about 30% of the time, so you have to 'over build':
* https://en.wikipedia.org/wiki/Capacity_factor
They have energy storage experts, so I'm sure batteries and such are taken into account.