Actually it can only deliver 100MW out of a load of 1000-2000 MW. So when all the wind farms lull at same time, the gas plants in SA and the coal plants feeding across the interconnect are what keeps the lights on, not the Big Battery. Mostly it will firm the adjacent Hornsdale wind farms variable output for a few 5 minute dispatch intervals, while the gas turbines spool up. It does not provide inertia so system must have a minimum number of dispatchable synchronous generators online, on that side of the interconnector to Vic, pursuant to the hastily-concocted, AEMO-inspired, rule-change.
It is really a big political stunt, playing on the ignorance of an ill-informed electorate and a clever, Teflon-clad State Premier.
