How much land?

Monument Valley, Utah (Source)

I've mentioned this before (I think) but it's worth repeating.  How much land would be needed for solar panels to provide all the electricity needed to power the whole of the USA?  Elon Musk:

“If you wanted to power the entire U.S. with solar panels, it would take a fairly small corner of Nevada or Texas or Utah. You only need about 100 miles by 100 miles of solar panels to power the entire United States.” 

 “The batteries you need to store the energy, to make sure you have 24/7 power, is 1 mile by 1 mile. One square mile. That’s it.” 

“People talk about fusion and all that, but the sun is a giant fusion reactor in the sky. It’s really reliable. It comes up every day. If it doesn’t, we’ve got bigger problems” 

Elon said a blend of many power sources would be needed at first. “We’ll need to be a combination of utility-scale solar and rooftop solar, combined with wind, geothermal, hydro, probably some nuclear for a while, in order to transition to a sustainable situation,” Musk explained. 

[Read more here]

Of course, we won't be building a single giant solar farm on these lines.  There will be many large solar farms but there'll also be rooftop solar.  The 10,000 square miles needed would be spread across many places, large and small.  Obviously Musk favours solar as the solution to our renewable energy needs,  but that's not a workable solution for high latitudes, where wind is a much more reliable source of electricity in winter, and even then you will need seasonal storage.  And a mix of wind and solar produces a more stable combined output than either individually.  But his point is well made.  In sunny desert places we need very little space to produce enough electricity, and even less space to make it dispatchable.