A blackout like the one they had would be bad. Possibly even worse than the one in the Dies the Fire series that Revolution ripped off...uh, is inspired by. The people in the Revolution blackout still have guns to make the killfest killier.
I think the absence of guns makes the Emberverse killfest worse, not better.
If there are working guns, you get a situation like Africa where warlords keep their supporters fed and it's the meek who starve. So it would be like the worst Ethiopian famine ever, but still within the range of human experience. The food would belong to the best supplied military force that could come up with a workable paper communication system the fastest.
Without working guns, there's no way to impose even evil
order. You get total chaos because for the first time in about 6000 years there would be no armed and trained rulership caste that can sacrifice some people to save the rest. You'd be left with people literally fighting over scraps of food with baseball bats and butcher knives.