As with most forms of energy generation/collection it depends on what you want to do with it. Power density with solar is pretty poor. And it produces DC (conversion is about another 10% loss). On the other side of the equation it's damn good for heat energy (well, there's a surprise). And your are absolutely spot on about the need for a stressed grid; properly managed, solar has a very low distribution loss.

Of all places in the world Australia should be a leader in this technology. We're not short of sun.