Keep your mobile phone in service, in the event of a power outage, by unplugging everything else from your computer’s uninterruptable power supply (UPS, or APS), uplugging it from the wall, and using it to charge your phone. Keep the phone topped off, but not plugged in continuously. You want to make the UPS battery last as long as possible, but have a full charge on the phone if the UPS quits.
If you feel you have to stay connected with your peeps, use text messaging only. Not only does it use a lot less battery, but texts are far more likely to get out on overloaded communications channels than regular phone calls.
If you don’t know how to send a text message, it’s time to learn.