We were at the Head of Bight free camp when the storms went through, and subsequently took it on the lam getting home in the resulting cluster that was rural SA.
I'm no expert on power grids, but I did witness first hand the p1ss poor condition of the power line infrastructure within SA. The power poles are rusty relics where even the concrete webbing they use in those stovey(?) poles is brittle and falling out, and the main trunk lines don't look particularly sturdy either; especially when compared to the powerlines we saw on re-entering NSW and later in Victoria. Irrespective of the mix of power generation, I'd say the SA government is besotted with shiny new "renewable power" generators that look and feel good, but it ignores the boring, not sexy belts and braces of proper infrastructure maintenance of the supporting grid.
BTW, on our way over to Head of Bight a few weeks back, Rural SA was just recovering from another major blackout that lasted days and extended just West of Port Augusta all the way out to the Nullarbor Roadhouse. That black-out didn't make the news, but talking to locals along the way, and witnessing the number of businesses who now have, or are about to buy a generator, I'd surmise the SA power grid is the least reliable in the country, despite being the most expensive in Australia and close to the most expensive in the (industrialised) world.
Wife and I went on this trip looking to move into SA in our retirement (we love the Flinders Ranges region, and we extended our house-hunting trip to Head of Bight to see some whales). I seriously doubt we will give moving to SA much further consideration now. SA, as much as we love it, has becoming an expensive, idealogically driven rust-belt.
Final observation from Ceduna where power and communication was restored, but lost again after a few hours; civialisation is a veneer just 1.5 days thick....