If you are thinking in terms of disaster planning, figuring out how to do things without electricity is a better use of your time and money than figuring out how to generate a lot of electrical power in the event the power grid fails long term. That said, there are a few things you will not wish to go without that are going to need electricity. One of those is communication. Sneakernet might be fine and dandy to get the town gossip in the PAW, but a radio is a lot better.
Claire and I made the switch to rechargeable batteries in 2005, a couple of years before I got the small solar array set up. We have never looked back. Right now, I have 120 volt wall chargers running off the deep cycle batteries that are, in turn, connected to the solar panels. If we lose grid power, all that will still work as it does today. In case the house solar is not working or if we need to charge some AA or AAA batteries away from the house, I have a couple of alternatives. One is a dedicated solar battery charger. It will take a 2400 mA NiMH AA battery from discharge to full charge in 8 hours of direct sunlight, and it charges 6 batteries at a time. Our GMRS walkie-talkies take 3 AAs each and run for a couple of days on a set, so that works out nicely. We also have a couple of very inexpensive two-way radios that operate on the same frequencies, but they use AAA batteries and don’t last as long.
In a pinch, I have harvested the solar panels and circuitry from a half dozen old decorative solar yard lights and can use them to take a 600 mA NiCad AA to full charge in a day. I had thought about using little sidewalk lights as indoor task lighting, say over the sink, but they produce so little illumination from the on-board LED that it is hardly worth the effort of taking them outside every day to charge up.
For light, we keep a variety of LED flashlights, headlamps and lanterns, all use the AA and AAA batteries that we can recharge using the sun. There are any number of solar or hand-crank powered gadgets that might be handy (or fun) to have in an emergency, so look around and see what appeals to you.
Here’s a solar battery charger for under $30. LINK