(b) Battery prices (and pricing for the balance of the system) have dropped pretty rapidly, I'm not sure why you're claiming otherwise. There have been recent years where these systems have dropped in price by ~25%[1]. That's not insignificant.
[1] https://www.utilitydive.com/news/not-so-fast-battery-prices-...
Was the decision taken years ago? This is the 100 days or free battery. But yes I accept the power companies may have been slow. But still it isn't just Australia that was slow, its the US, Germany, Denmark, the world.
Not exactly.
Australia's high prices were not due to a technology failure, but a regulatory one. The power generators were manipulating the market causing extremely high peak prices, and essentially being allowed to get away with it. Most other countries don't allow the market to wildly fluctuate so much, so the payback is far longer. Think decades and not years.
Not many investments offer that rate of return.
You may be right to suggest it may not be competitive in other locations though. I don't know.
https://www.greentechmedia.com/articles/read/tesla-fulfills-...