When I had a similar problem (power outage) I stuck my eggs in an egg carton, pointy side down, put it in the oven (top shelf) with a bowl of water on the shelf below it & a candle burning under the water bowl, door closed. It was years ago, can't recall what day of incubation I was in and it was for a few hours before the power went back on & back in the incubator they went. Had only 5 eggs, 4 hatched.
Another idea I've read here was using a heating pad wrapped in a towel, not direct heat but using as a heating element to keep eggs warm. In a container, make like a nest for the eggs, don't forget to add some humidity.
Good luck