Even during the ice storm you could get fuel in areas that did not have power. They used generators as well. It would still be possible to get fuel, unless the world runs out of oil.
I keep generally 100 liters of gas on hand, well 80 liters now as one can needs to be replaced. The generator is kept full. I also test the generator twice a year spring and fall and run for about 30 minutes to make sure it's working good.