What you are looking for is called a book. It does not need power or internet, just light to read. The SAS Survival Handbook is good for all around advice.
Well, the most likely natural disaster here will involve my immediate local area being under about 5 meter of water, so either I'm elsewhere and in need of a map, or... well, not in need of a map.
That's great for an emergency kit but you never know when something will happen and if you'll be in a position to get back to your kit. Seems pretty worth.