You say 'did you look at a map' but have you looked at a topographical map? I don't see much room that isn't either protected forests or the Appalachian mountains, in some cases it's both.
Well, I don't know enough about the industry to analyze specific locations, but it's easy to find real-world projects in upstate NY and elsewhere: https://www.solarpowerworldonline.com/2020/03/large-scale-so.... The projects named in that article will apparently get more than halfway to the "11,000 megawatt hours per day" estimate.
Anyway, the more important point is that we already have large regional grids across the country, and while it's obviously nice to have generation and consumption close to each other, it's not a requirement.
Why do you think solar and wind could not be built in the Appalachian mountains? Wind in particular would benefit there. And the mountains are an excellent place to build off-river pumped hydro storage facilities.
Anyway, the more important point is that we already have large regional grids across the country, and while it's obviously nice to have generation and consumption close to each other, it's not a requirement.