Kripke wanted to explore the story on the "other end" of that.
"We're not interested in nihilism or hopelessness. We'll all survive and be OK if we remember the things that bring us together: family, brotherhood and mercy."
Ultimately, though, as McGee points out, "What 'Revolution' needs is what every show needs: five characters people care about. Why the lights went out turns into a bit of boring trivia without that emotional investment."
The rules of great TV are the same, even when the world seems to be coming to an end.