South Australia - where the battery is located - is an outlier in the Australian market due to its relatively progressive energy generation composition. It's worth noting the battery charge/discharge values depending on the market price of wholesale electricity. Arbitrage in action! :)
The application is open sourced and available here:
Our largest 3rd party, the greens just won't even consider nuclear, to them it's solar/wind or bust.
Of course, they have not actually done anything at all, which is the definition of Australian politics.
That said, you would think that the gas generator company could just bid the load they've agreed to supply under the long term contract into the spot market when the price dips negative. I assume there is a good reason why this isn't done.