[toast0]

> I also think you would need more than 24 hours battery. You have to prepare for freak weather events that reduce system capacity.

In general, yes. Not really in the context of utility generation for a DC, though. A DC should have onsite backup generation, at least to supply critical loads. If your contracted utility PV + storage runs out, and there's no spare grid capacity available (or it's too expensive) you can switch to onsite power for the duration. The capex for backup power is already required, so you're just looking at additional spending for fuel, maybe maintenance if the situation requires enough hours on backup.