My father runs a natural gas generator for his whole house. You might want to look into one in you own a home.
Basically, if the power goes out, the generator senses the loss of power, then begins to convert natural gas into electricity to power your home.
The units installed can range anywhere from a few thousand, all the way up to 10K, depending on how much electricity you're needing.
Definitely something I'm going to look into when I buy a house. They're not only good for our aquariums, but during storms they'll run you sump pumps so that your house doesn't flood from rising water.