It would take 460 Tesla Megapack 2 XLs to be the same capacity as this. The biggest deployment so far of those is about 200 Megapacks 1 giving 450MWh capacity vs 1,800MWh for this.
The lithium batteries can supply the same power (300MW) and cost $160M. This cost $207M, so quite a lot cheaper given 4x the capacity.