[Sherman Logan]

You would have to cover an area the size of Massachusetts with solar panels to provide the energy to marginally power a city of 100,000.

I agree with your general point. But I think this example may be a tad hyperbolic.

According to this site, it would take 2907 acres of panels.

http://www.boemre.gov/omm/pacific/kids/Power-Your-City/bookmark-1-page%20side-by-side.pdf

I don't know that's right either, but I believe MA has a lot more acres than that.

If you have an actual number for the power consumed by this imaginary city of 100,000 we can do some calculations.

[chimera]

I am wondering how well those 2907 acres of solar panels would do powering the city of 100,000 during the night. My guess is...not very well.

[Partisan Gunslinger]

According to your numbers it would take ~14000 square miles to power the United States. A square of ~118 miles on each side.