[petrocrat]

All energy has externalities, fossil fuel externalities are much worse. Why object to the externalities of solar in particular here but not the externalities of what it replaces?

An honest comparison would only judge the externalities of solar in the light of the externalities of fossil fuels it is replacing, and not in isolation as you are doing.

While solar may use the grid as a giant battery, fossil fuels are using the atmosphere as a giant garbage dump. One of these is obviously much worse.