How to Build a Water Bottle Skylight

 

I spend a lot of time looking at appropriate technologies coming from missionaries and other groups that work in third world countries.

I figure – if it works in areas lacking infrastructure then it will work if we ever lose our infrastructure.

This idea came from a couple of YouTube videos I saw of people making water bottle skylights out of 20oz soda bottles.

This is also called a solar bottle bulb.  Either way, the concept is pretty simple I have used this in domes and animal houses several times.

Most specifically I got it from the video at the bottom of this page.

I modified it slightly and was quite pleased that two of them gave enough light in my cement dome that I can see what I am doing.

Actually, if I am in the general area of one of the lights I can actually read by the light.

This technique was used on my Dome of Doom on Doomsday Preppers and it works very well.  I have a series on how I made my cement EMT dome.

 

Parts:

• 1 clear soda bottle
• Water
  Bleach
• Plastic roof flashing
• 2 eyebolts
• Wire
• Duct tape
• Mylar space blanket

Procedure:

• Drill two small holes on opposite sides of the plastic flashing, and thread the eyebolts in the holes
• Fill the bottle with water, leaving enough space that you can add about a ¼ cup of bleach to keep anything from growing in the water.
• Cut the mylar blanket into a strip approximately 1/3 the height of the bottle.
• Center the mylar strip in the middle of the bottle and wrap it tightly – you need to leave unwrapped bottle at the top of the bottle to gather light, and at the bottom to release it. – Basically you are making a reflective tube to channel the light.
• Insert the bottle into the flashing, leaving about 1/3 of the bottle sticking outside the top of the flashing.
• Wrap wire around one eye bolt, pull the wire tight over the bottom of the bottle, and then secure it to the other eye bolt – this keeps the bottle from dropping out of the flashing.
• Insert the entire assembly on your roof and calk as needed to prevent leaks.

Note:

Over time UV light will degrade the plastic – but since soda bottles are everywhere, it is a simple process to rebuild as needed.