Lighting / Power
A candle is one of the simplest forms of emergency lighting there is, and gives off a bit of heat. A few steps up from that and we have a progression from flashlight to heavy duty batteries, inverters, "normal lights", and maybe even a generator or solar panels to recharge the batteries. Solar panels won't help in sunless (storms, ash clouds, etc) events, or in EMP events where electronic equipment like inverters and solar panels could be fried. You have to examine what events are probable, and within your ability to prepare for. A propane powered backup generator, with solar panels, deep cycle batteries and a good inverter, is a good all around solution for most events. If you have medical supplies that need to be kept cool, a small fridge might be necessary. A propane fridge can be a nice non-electric (some require electronic controls, others don't) solution for emergency medicines like insulin.