Search on properties

Type of initiative

Field of work


Search on keyword

You are here:  en  /  Initiatives  /  Liter of Light
back to the overview

Liter of Light


Hundreds of millions of people worldwide live in informal settlements. Many of these chock-a-block dwellings lack windows or adequate daylight, and in tropical areas they are often made darker by extended roofing for protection from rain and hot sun. The results are rooms and shacks that are dark even in daylight. Residents of informal settlements often resort to kerosene, candles or inventive wiring for light; risking health and safety in the process. Many simply go without light. Proper electricity is not a common option.


In order to tackle this problem the Filipino entrepreneur and activist Illac Diaz created Liter of Light to provide informal settlements in his country with a cheap daytime lighting source, that can be produced and distributed locally. His idea is going viral, and worldwide people are using clear plastic soda bottles filled with water and installed in the roof as a skylight. This simple technique called “Liter of Light” proofs to be a very sufficient light ball, a 55 watt solar bulb. The water refracts the sunlight as it streams through the bottle, dispersing the rays 360 degrees, thereby illuminating the entire room. The recipients of the solar bottle bulbs, who pay about $1 for the bulb and installation, save money on electricity or cut back on the use of kerosene, candles and other fuels that are responsible for indoor air pollution and fire hazards.


Liter of Light is not a charity: It provides enough initial supplies and volunteers to generate interest, but its focus is on teaching a community how to manufacture and install the solar bottle bulbs, with the end goal of creating green micro businesses.


Liter of Light started in 2011 and is now widely distributing the technical know-how to produce the solar bottle bulbs, and through a combination of social networking, community outreach, open-source sharing and hands-on building, the organization has placed tens of thousands of these solar bottle bulbs in informal settlements worldwide.


The campaign started in the Philippines, but has spread beyond Southeast Asia to India, Nepal, South America and Africa. To date, the solar bottle bulb has been installed in over 30,000 homes in the Philippines. Around the world, Diaz estimates the number of installations is roughly 110,000. There are small adaptations to the design along the way. “In Nepal they put a little bit of anti-freeze in the water so the bottle doesn’t expand and contract,” said Diaz. “In Africa, in the thatched houses, we tied three plastic bottles together and put a stick in between, to attach them to the roof.”


The project is fostered by the MyShelter Foundation that aims to brighten up one million homes around the world by the end of 2015. The Foundation has many volunteers worldwide that invest time and effort to install the bottles in places that need them. They describe it as a great teambuilding experience to literally spread the light. On the website you can find an instruction video that shows how to build and install a solar bubble yourself.


Watch the mini documentary below.


Click here to read our news item on Liter of Light “Light from a bottle” from July 2013.




Permalink  |  Share




Type of initiative Action/campaign organization, Information/network organization
Field of work Other (non-profit), Other (specify): durable energy
Date of commencement 2011
Founder(s) Illac Diaz
Legal form Foundation
Continent Asia
Country Philippines
City Makati City
One or several keywords that describe your initiative Liter of Light, solar light bulb, durable energy, Light from a bottle
Publications Videos, articles, photos
More information

Contact person(s)

Illac Diaz


Contact information

Name A Liter of Light
Address 11th Floor, Insular Life Building
Zip/postal code
Place Makati City
Country Philippines
Phone +632-9189403513



View all initiatives