I remember one Sunday morning a few years back, I got up at 8AM, and at 8:05 the power went out. I forget what the storm was but I had made preparations. By 8:30 I was serving bacon and eggs with toast, and my coffee was hot.Ok then so lets rephrase the question and make it a smaller scale local emmergency where you may need to live off grid for a few weeks
A few weeks is no problem for me. Even during the winter I keep a spare full tank of propane for the BBQ grill. I can cook a large dog in there.
For everyday I also use propane, but in the small (expensive) bottles; I typically buy 1-2 pairs when I see them go on sale and have a large supply now. That keeps my lights, heater, and alternate stove going.
(Meanwhile, when Sandy took our power out my wife freaked out after 3 days and so we bugged out to Ohio till power was back.)