In South Africa they call this
Load Shedding, but currently there is no issue. In the summer of 2015 there was 2.5 hours every day a blackout. I noticed that most ATM's and supermarkets worked normally, due to backup diesel generators. So it is much more prepared than here in the EU.
But back to SA, it is completely powered by wind ? I thought that Australia is, like South Africa, addict to coal power stations, despite both countries have much more sunshine than the EU.