1. Charge up every laptop in your home. If you lose power, turn a laptop on (but don't unlock the screen) and use your iPhone or Android cable to charge your phone via the USB ports. Most newer laptops can charge a smartphone multiple times.

2. Keep your phone on "Low Power Mode." This setting will use far less juice. On an iPhone, go to "Settings," scroll down to "Battery" and turn on "Low Power Mode." On an Android, swipe down from the top menu and find the "Power Saving" icon.

3. Use your car to charge your phone. Most newer cars have a USB port – or two. Even if your car is out of fuel, you can turn it on and charge it using the car battery. It's a last resort, but if you have a newer car battery, it will charge a phone multiple times easily.

4. Buy an external charger if you don't have one; most drug stores have them. Portable smartphone battery chargers are getting better and less expensive. Most drug store chains have them near the counter, but you will pay more for the convenience. But if you need one right now, that is a good place to look.

Companies such as Anker and Aukey sell high-quality, high capacity chargers on Amazon. Consider buying one before the next storm. Some of the new one have capacities approaching 30,000 mAh, which is enough to charge an phone over five times.