Let there be Light: Solar Bottle Bulbs Illuminate Filipino Cities

When a group of imaginative students at Massachusetts Institute of Technology (MIT) first designed an experiment to make light emanate from plastic water bottles, they never imagined that their minimalistic idea would literally and metaphorically light up the lives of over 15,000 people.

The idea seems deceivingly simple: take an empty one liter plastic bottle, fill it with purified water and a few drops of bleach for cleanliness, and cement it halfway through a small metal roof sheet. The plastic refracts sunlight and suddenly illuminates every corner of a dark room.

But while its physics is straightforward, its impacts have been far greater than any of the original designers could have imagined. Many slum homes in developing nations lack proper lighting because of how closely they are constructed in relation to one another, and the families often cannot afford the luxury of electricity. Over three million families live immersed in darkness in metropolitan Manila, a Filipino city where the bottle of captured light has made the greatest difference.

Filipino student Illac Diaz, the creator of the My Shelter Foundation, has made it his personal mission to brighten one million homes in the Philippines by utilizing this elementary yet ingenious invention. He calls his project Isang Litrong Liwanag – A Liter of Light. Today, with the help of various organizations and individual volunteers, Diaz and his solar bottle bulbs have lit up over 15,000 homes in over 20 Philippine cities.

Although it is not a perfect technology because it does not produce light during the nighttime hours, it is surprisingly effective in the sense that it uses inexpensive and locally available materials to illuminate homes that had never experienced the luxury of light before. The MIT students’ science along with Diaz’s motivation have extended this project’s impact beyond providing light.

The success of A Liter of Light is a great model of a sustainable solution for a variety of socio-economic problems worldwide. It is an idea of Appropriate Technologies, a concept that provides a simple, replicable technology that fulfills the needs of developing nations by utilizing the limited resources they have access to.

And the Philippines aren’t the only country. From the jungles of Uganda to riverbanks of Bangladesh, these solar bottle bulbs are continuing to make their mark on countries all over the world. And for those families that now have these makeshift light bulbs in their homes, something that spreads a stray ray into the darkest interior can be much more than a bright idea.

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Angie Lou

Source: Let’s Talk Magazine