My headcanon for The Matrix’s “humans are batteries” is that it’s the machines’ perverse interpretation of this — killing the humans is off the table, and for whatever reason letting them live with no purpose to serve the machines is also disallowed. But giving their lives “meaning” in the form of a shitty (and thermodynamically dubious) “battery” somehow satisfies the rules.
It’s a very big stretch, I’ll admit…
Remote backup server would be my suggestion.
Configure it with a VPN to talk to your home network and set it up at a trusted friend’s or family’s place.
I do this with a raspberry pi and an external HDD that takes daily/weekly/monthly snapshots, with daily rsync. Works nicely for me.