Hi Luciferase,
I hear you - I really do. It's why I still am pro-nuclear.

But the thing is - Germany spent all that money decades ago on renewables scaling it up to bring the cost curve down. And it's STILL going down. China is expected to drop solar 30% this year! There's a price war going on.

You're comparing the money invested decades ago with the prices today.

That's like comparing a Gen1 nuclear plant with today's developments in Gen3+ - it's cherrypicking and just not rational.

Western Power can't even do its own arithmetic. Walpole consumes 0.4 MWhr of energy each HOUR (on average over a day) not each DAY! Multiply by 24 (hours in a day) and you have 0.4 x 24 = 9.6 MWhr. It's worse than I calculated using Perth figures, and actually closer to 3 hrs than 4 hrs of backup! Even this presumes the dam is always full and ready to go, after possibly multiple days of grid failure. 75 hours is fanciful nonsense and you should be able to do the calculations yourself to establish this if you are to have any credibility. I respectfully submit that Walpole and Snowy 2.0 are walls and poles apart.

You really are clutching at straws, Max. France's Messmer Plan cost less than a quarter of Germany's investment in intermittents to achieve it's carbon intensity result. Inflation is barely relevant. If nuclear had been given the chance instead of being stymied by over-regulatory, ideological forces, it too would cost 30% less now. Don't even go there.

One path is proven success on emissions, the other is proven failure. The choice is simple, and affordable if we let the Koreans go to work here.

Max, I awoke with a start this morning at my late night stupidity. WP's calculation is indeed correct and it is I who's credibility is questionable, not yours or WP's. By my own reckoning 30MWh/9.6MWh/day = 3 days = 75 hours. Reduced a little for conversion losses and you have the roughly 70 hrs. There was no need for you to do a calculation as WP's was correct, and I was wrong to berate when I was at fault, not WP, or you.

If you can look past this, it demonstrates that for a 3-day grid failure, the situation is covered when the dam is full (which it should be often as it's largely recharged from the grid). After that, out come the home generators, or a central one to service the whole town.

It's the last bit that makes a difference. Whatever the storage method, how much is needed is an unknown question, even before weather dependent generation itself is is affected by climate change (longer wind and insolation droughts). There will always be the need for fossil-fuelled backup with intermittent generation and storage (no point in nuclear for backup purposes as it makes the generation and storage redundant). This is too much expensive infrastructure needing continual renewal and ongoing of emissions to making one clean, reliable, affordable system (without mentioning the enormous grid upgrade needed to accommodate it).

The remainder of what I said re Germany and France are true, only one path to nett-zero is proven and affordable, while the path Oz is on is not.

Apologies again, but I can't thank you for winning the path war.

South Australia does 10 days 100%
http://reneweconomy.com.au/south-australias-remarkable-100-per-cent-renewables-run-extends-to-over-10-days/