Mouse is correct about the power plants and the people who live around them.
Have good friends who lived in the shadow of a cooling tower. No kidding, from their back window see the steam clouds. They moved but not for the plant, but two neighbors were real A-holes.
But a lot of the plants workers lived in the neighborhood. They are very motivated to make sure them and theirs dont get irradiated. And they are mostly too old to bug out.
The question is, have some of them sat around and thought up a way to keep the power going, at least locally?
Wasteland does bring Mad Max, desert wasteland (or CA) to mind.
But unless there is some major weather pattern change, we get up to 22ft of snow a year, and a good bit of rain too.
Loss of the grid for a prolonged period of time, say a year or longer, the population would see a serious decrease.
Living in caves? No.
I look to my Amish neighbors, and we all would have to adapt their kind of lifestyle. They can read, write, speak at least 3 languages, make a lot of things by hand, are dang good carpenters, know all about horses, and making things by hand.
Us English (as they call us) know we are going to need them for survival. And they may need us for self-defense.
Upside, myself a more than a few neighbors have differing skills, and we all have a lot of books on various skill sets.