I'm on the A320 so not that clued up on A330 system differences, so if you went into EMER ELEC you would expect the RAT to deploy. If the RAT was to fail/damaged in wx/not deploy - How would that leave you power wise ? Would be down to 30 mins BAT only ?
If you were down to BAT only - that would put you in ALTERNATE LAW.
How quickly on the A330 would the cabin pressure become an issue ? The A320 leaves you with enough time to descend down.
Once the batteries are dead - I presume the ISIS would fail too ?