Practical Engineering has an excellent series of videos that explain in non-technical language how the power grid works and how it fails. It's frighteningly vulnerable to even a small disruption, in spite our best efforts to make it more resilient. Maybe your friend should watch this.

How Long Would Society Last During a Total Grid Collapse?
youtube.com/watch?v=_OpC4fH3mE

Playlist for the entire power grid series:
youtube.com/playlist?list=PLTZ

@chu