Musk stated in the presentation that they plan to use solar with on-site battery storage at these "Mega-Charger" stations and will guarantee a max electricity c

Musk stated in the presentation that they plan to use solar with on-site battery storage at these "Mega-Charger" stations and will guarantee a max electricity cost $0.07/kWh. No grid needed (my phrase, not his). Not sure if it is doable, but that is the plan.