Planning for a Power Outage

[Werbo]

Hey all

I recently moved to the outskirts of Victoria. Last year in my new neighboorhood there was a power outage that lasted over 48 hrs.
In case this happens this year I wanna be prepared so my sps frags and other livestock survive.
I'm assuming the frags will be ok without light for 48 hrs. So, what could I buy to keep my heater and powerhead running in case of a long power outage. Anything cheaper than a generator that will work?

Also where could I buy such equipment.

Thanks, Tyler