Filipinos have found a new (and practically free) way to use an old source of light, and it’s something you can put into your survival playbook to provide light to a shelter if the electrical grid ever goes down. You can also use the method to provide light to an outbuilding that doesn’t have an electrical connection.
All it takes is a clear, one-liter soda bottle, some water, chlorine and little simple engineering. Fill the bottle with a mixture of water and chlorine, cut a hole in the roof and secure the bottle and you have 55 watts of free and simple solar lighting.
Watch the video to see how it’s done.