We often have power failure at work, couple times a month and we have never lost data. Our backup is done nightly, I think it starts at either 1 or 3am, with the main one weekly. We are only small and still able to keep backups so something is not right there. Tell your DH to stop stressing as a few powercords removed will not wipe data.

If you shift or turn off your computer you don't data.