Ray,

Thanks for the comments. Here is the generator I was thinking of getting:

http://www.electricgeneratorsdirect.com/catalog/product_info.php?products_id=608

From it's description it uses 2.2 gallons per hour, but I am assuming that is at full power. I am thinking, if I need to use it after a large earthquake (where the normal natural gas is shut off) that I will have it on for a small person A/C unit and a few lights at night.

During the day I would not need it half as much. I will have smaller personal propane tanks for stoves and such.

I was thinking the 40lb tanks because then I could use a dolly and transport them to a truck or 5th wheel if needed. That way if we ever need to bug out, I will have options.