Soda Bottle Light Bulb

Being born in Venezuela and living there for 9 years, I remember visiting my grandmother (who lives in a small village 8 hours from the capital) and having to adjust to the power outages they would have every couple of hours and would last for about 2-3 hours, this would happen since there was no maintenance being done to the power sources in that area and I remember being frustrated since you would have to stop your activities such as watching TV,  drying your hair or  even cooking until the power came back on. Recently, I came across a story about some students at the  Massachusetts Institute of Technology who invented a super cheap way to produce light with a soda bottle, chlorine, purified water, roof sheet material and rubber sealant. The product is called the solar bottle bulb and it works by combining the water and chlorine into a pop bottle and by exposing it into the sun it can illuminate a small space, they also can last for about two years  and it can produce the same amount of light as a 60 Watt incandescent light bulb. This is such a great product for developing countries such as Venezuela that have very limited access to electricity  since it doesn't take many materials to make and are also accessible. Gotta remember to show this to my grandma next time I visit her!

Below, I have added the instructions into making these unique light sources:

1. Fill the clear soda bottle with purified water and adds 3 tablespoons of liquid bleach or chlorine. And tightly seal the cap. Note that purified water is needed because moss will not grow in it, unlike tap water.

2. Cut a hole in the roof sheet as big as the diameter of the bottle. Make sure that the other half of the bottle, starting from the cap, is exposed so that it could capture sunlight.

3. Make a hole in your roof, the same size as the bottle (not the roof sheet).

4. Insert the bottle with the roof sheet in the hole of your roof and seal it with a rubber sealant to prevent leaking due to rain.

It will produce light when the bottle is exposed to the sunlight. It is expected to last for 2 years before you need to replace it.

All info and images from: http://www.sustainableideas.it/2011/11/20/solar-bottle-bulb/