Once again, our friends over at reThink Survival have ponied-up to the bar with a very informative post, comparing different modes of lighting for grid-down blackout conditions. This is, of course, a very important aspect of emergency preparedness, from a safety and convenience as well as a psychological perspective.
As human animals, we instinctively fear the dark. It's in our very DNA. In fact, I've found that full-dark actually keeps me from sleeping, due to an odd hyper-vigilance reaction it brings out in me.
Therefore, no survival kit is complete without taking lighting into account and having a backup... and a backup for your backup.
Here at the homestead, we have several rechargeable battery-powered LED lanterns, two kerosene lamps, a slew of candles stored in old coffee cans, and a bunch of rechargeable batteries for flashlights.
The rechargeable LED lanterns are plugged-up at all times, ready for action if/when the lights go out.
One of my next purchases will likely be a solar charger for my rechargeable batteries (like this or this). The LED lanterns were purchased from Ebay about 5 years ago for $12-$15/piece, and are still holding-up just fine.