I should have mentioned that
I should have mentioned that in the Northeast, they're trying the same thing using wind. Where I live, that would be the best option.
My brother-in-law in California has solar arrays on his home that power his house, a rental house, and often have some left over during the day. It's entirely possible in some parts of the world for that to be the case.
The point is, though, that the hydrogen created (rather than stored or sent into the grid - not nearly as cost-effective as the green pundits would suggest) can be used effectively in other elements of the home (namely heating) and used to fuel a car as well.