Plus, Australia has hydro, which can be varied to fill the gaps.
Renewable power is cheap in the same way someone whose head is dipped in liquid nitrogen and whose feet are in molten lead in over all pretty comfortable.
That's a bit like saying that there is no point in growing crops in Europe, because of the winter.
In fact, when it comes to food production (which is really just a form of energy), there are 3 major strategies how we deal with winter: storage (e.g. granary), shifting production (e.g. eating a pig you raised during the year), and trade (e.g. buying oranges from a tropical country).
We can apply all these to electricity as well.
Which grid can store enough energy to run for a week if all renewables are offline?
Hint: there aren't any.
But the technology does exist, and it's gonna be deployed eventually.
[[citation needed]]
https://helioscsp.com/the-cost-of-concentrated-solar-power-f...
That solar is cheaper at noon doesn't mean much. It's a bit like saying that coal is free underground.