Saturday, June 22, 2013

Solar Light Concept: Get Free and Natural Sunlight to light up your home/office!

A few blog posts ago, we had showcased some of our innovations in construction related technologies at Ideas Unlimited. We did some Googling around for some innovative way to use natural light into the building. Some of the innovations done by people around the world on this front inspired us to do something similar in a more engineered fashion which looks elegant as well!

This idea is pretty simple. If you are into a bit of hands on Engineering, you can probably do it yourself too!

And the best part of this whole thing?  You don't have to pay for lighting up your home ever! You are harvesting natural sunlight for free from your roof! 

The system is so simple and maintenance free to make, that it is a one time investment that benefits you for life! We have put in some engineering aspects to make this into an elegant option and make it more appealing for people to adapt it even in their expensive homes and for commercial buildings.

Step 1: You have to make a  perfect template for putting the bottle in as part of roof centering. (If you want we can make them for you.)
Step 2: You need a large Candy or Toffee jar which is at least a foot high. Stainless Steel Cage gives a lighting fixture like feel at the bottom, while also aiding in any eventuality where the glass is broken accidentally for replacement bottle! Cage is custom designed by us.
Step 3: Use the template along with the metal sheets for centering. Place the cage and bottle inside. Now the bottle is part of the roof centering, ready for casting.
Step 4: Roof Casting
Step 5: Roof is cured. Bottle gets embedded into the roof. (You may have to clean the bottle surface)

Inspection before Centering is removed.

Step 6: After roof centering is removed! Bottles lay exposed. (This photo was taken with the camera flash on because nothing was visible in this dark area).

Step 7: Open the bottle lid, fill it with clean and pure water (preferably soft water) and add clear liquid bleach into it. The bleach prevents any kind of algae growth inside the bottle and also helps in diffusing the light the bottle captures.
Step 8: Observe Below and VOILA you have more than a flouroscent light worth of light (Tube light) from a natural and clean source and you don't even have to pay electricity bills for this light!(This photograph was taken without the camera's flashlight using the natural light in the place. Once the roof is painted white and walls painted, the light is expected to improve further)

If you are interested in using such lights, but unable to make the necessary materials required yourself, do get in touch with us at or (Strictly e-mail inquiries please).

Given both our companys (Ideas Unlimited, Ideas Manufacturing Mysore Private Limited) interests in Energy efficiency and Energy Saving systems, we are more interested in promoting this technology. We also intend to offer these in a product format shortly in the near future...


Of course, we DID NOT invent this idea. We were inspired by the Coke Light concept prevalent for many years in Philippines and the information available in public domain for this idea.

Video of the Filipino innovation in using Coke bottles for lighting up homes.

We however did  use our engineering skills to ensure that the process is achieved in a trouble free manner, with a HIGH QUALITY finish and easy maintenance. We made the concept better in this endeavor.


  1. Superb, people at villages should use this idea, This is something like mangalore tiles with glass, where you get light free of cost.

  2. How do we replace the bottle if it gets broken? Also what is done to prevent water likage from the space that may develop between the outer edge of bottle and the concrete?

  3. Hi Anonymous, the stainless steel cage that holds the bottle in the roof has 2 purposes:

    1) Aesthetics - It makes the bottle look like a professional lighting fixture.
    2) Life-saver in the event of bottle breakage due to some reason.

    Replacing a new bottle:
    The cage is embedded into concrete at the right level. The plywood sheet for centering to hold the bottle ensures that. That way, in the event you have to replace broken bottle, just remove all the glass piece, and chip off a bit of concrete, place new bottle into the cage that is permanently embedded into concrete, then pack it with new conrete/mortar.

    Water Leakage?
    Experts in concrete technology say that glass is a different form of sand and cement bonds very well with glass. (For example, have you seen cracks develop when people place solid glass blocks in roof or walls?)

    However if such a crack/opening does develop, a tube of Silicon sealant should do the trick.

    This roof in picture is about a month old now, so far no issues. Will post on the blog if something does happen.

  4. Very innovative and nice way to showcase a pre-existing idea with engg. support... Way to go nagendra! - Deepak


VIjaya Karnataka report on Project Pratinava (Silo) designed, Built and deployed by Ideas Unlimited

Reported on 18-Aug-2018. This report appeared in Vijaya Karnataka, Kannada language newspaper on 17-Aug-2018. Two other companies base...