I personally think that it is impractical, as you generally need 220 - 240 VAC in your house, though a few e-bike front lights may be useful in a power cut, to light up dark corners.....
There are DC to AC converters for making the mains AC from batteries, but they generally need either 12 or 24 DC as an input, as they are most often used with Lead Acid Batteries.
It is probably best to have a few LED flashlights around, one per person would probably be best, and buy ones with 18650 Cells, to give you the longest power on time.
A few camping lamps would also be a great idea to have, rechargeable ones of course!
A wood burning fire/stove can give heat, without the need for electricity, which if bought carfully, could also heat water, or do some basic cooking as well.
Some have a back boiler, and give the possibility of showers or bathing, without any electricity of any kind.
I had a Franlin wood burning stove (acually two, one in the lounge and one in the dining room, no central heating at all!) in the UK many years ago, with a swing out grill (on a hinge) that made fantastic steaks ready to eat as well as holding a kettle over the flames when needed....steaks need that the wood has burned down to a really hot glow, with little or no smoke by the way.
Old pots and pans do not care if they get a bit black, and still manage to do their job well.....
Best wishes.
Andy