The real problem is...
...that the treehuggers and luddites won't like the
idea that there would be millions of kilowatts
of microwave energy beaming into a confined
area on the planet Earth to be converted into electricity.
They have more political power and influence than we zoners have,
and they would kill such a project.
As far as to the engineering viability of making and establishing enormous fields of
solar-panels on the surface of the moon....It will cost the taxpayers tens of billions of dollars,
but that's NASA economics for you.