There are obvious ways to get some juice in your gizmo, such as using a hand crank or a battery pack.
Others involve hacking a 9v battery or even plugging your smartphone into a piece of fruit.
However, we’d advise you to avoid trying some methods of getting power in your phone, because you could damage your gadget AND yourself at the same time.
You could also try making your phone last longer by deleting these apps.
But where’s the fun in that?
Here are some of the wacky and sensible methods of charging up your phone during a power cut.
Hack a 9V battery
This method requires a 9V battery, the spring from a pen and a car charger adapter.
All you need to do is connect the metallic point of the car charger to one of the connectors on the battery, before attaching the spring to the other.
Finally, just connect the other end of the spring to the charger.
However, Matthieu Dubarry, an electrochemist at the Hawaii Natural Energy Institute and battery expert, told Mail Online that this method could blow your phone and cause an explosion with “as much power as a hand grenade”.
“There’s a risk, and we don’t want people getting hurt because they tried something off the internet without knowing about it,” he said.
Don’t try this one at home.
Build a battery from FRUIT
This is another dodgy method which could damage your phone, so proceed with caution.
You can see what to do in the video above, which comes from the YouTube channel LifeHack2012.
First you need to get a number of pieces of acidic fruit, such as lemons or oranges.
Then get one zinc nail and one copper nail into the fruit, making sure they don’t touch.
Use copper wire to connect the zinc stuck inside one piece of fruit to the copper in another, so they form a circuit.
Then open up the USB end of your charging cord and connect the cables inside to the copper wires.
Theoretically, this should generate enough power to charge your phone – but there’s a major risk you could damage it too.