The best idea is to rent or buy a generator. Otherwise, you can get battery operated air pumps at either your lfs or in the fishing department of Walmart and stock up on batteries. You need to aerate the water to keep the oxygen level up.
Hopefully, you will not have heat or cooling issues at this time of year. If your tank gets too cold, you can wrap it with blankets. There is not much you can do if it gets too hot, unless you have a generator and can run your chiller.
Good luck!