Have you considered any of the solar “generators”? Basically they incorporate a solar controller, inverter, and battery into one easy to use package. I typically get at least one outage/year here in the Midwest. I bought a kill-a-watt to measure what my fridge is using (about 2kwh/day) and it looks like one of these devices could keep that running through a longer outage. If you want to go even further you can buy more batteries!