When it comes to dealing with Mother Nature, I only have one thing to tell you: work with her rather than against her. Look up the local farmers and see which ones have broody hens (or turkey, or peahen, or... well, you get the idea). With some luck you'll find a few; discuss with the owner the possibility of you coming over for an emergency incubation if the power outage shuts down your incubator. DON'T buy the broody hen from him in advance; the shock of the transport and change of coop can deter her from brooding. Let her brood your eggs in familiar territory, then come fetch mom and chicks when they hatch. The farmer can get his emergency broody back when the chicks no longer need mama, and if you spot cockerels in the lot, send him some too as thanks for lending you one of his hens.
Note: Look for hens that have gone broody at around the same time you've placed your eggs in the incubator. A hen that's been brooding for almost three weeks is not one you want to put your eggs under, as she will abandon your eggs in favor of saving herself if hatching them takes an unusually long time. Target hens from brooding breeds (Cochin, Brahmas, Silkies, etc), note down all potential mamas, and see which ones would be ready to welcome your eggs if a power outage happened. Broody hens aren't picky when they want chicks - any egg they can claim becomes theirs.
This might sound far-fetched and pulled out of my hat, but honestly if electricity fails and generators run out, a broody hen will be your best (and perhaps only) bet of saving your eggs from a cold doom. If you can afford it, then it's worth a try.
