Plastic bottles give San Pedro light

Friday, 4 March 2011

SAN PEDRO, Laguna, Philippines—For at least 450 families here, plastic bottles have an unusual function in their homes—providing light without electricity.

“I couldn’t believe it myself but I thought there’s no harm in giving it a try,” said resident Morico Albao, 46, when the Solar Bottle Bulb project was first introduced.

“If there’s even a slight leak, I’d have to ask these people to replace my entire roof. But so far we have not experienced any when it rained last time,” said another resident, Juliana Vista, 68, who was apprehensive at first about the idea.

Solar Bottle Bulbs use the sun’s energy. The device—mainly a plastic bottle—is fixed on the roof of the house, protruding from the roof so the upper portion absorbs solar energy and the lower portion produces light.

The technology was developed in 2006 by students from the Massachusetts Institute of Technology (MIT) in the United States and has been used in poor communities in Brazil and Mexico.

In January, My Shelter Foundation, in partnership with the Rotary Club of San Pedro South and the local government, adopted the technology and introduced it to families living in shanties in Barangay San Vicente here.

How it works

The device would only need the following materials: a used plastic bottle (preferably a 1.5 liter soda bottle), 1’x1’ roof sheet material, purified water, chlorine and rubber sealant.

On the roof sheet, cut a hole to the size of the bottle’s circumference. The bottle is inserted through it, with the bottle’s upper 1/3 on one side and the bottle’s lower 2/3 on the other.

Next, fix the device firmly on the roof of the house, with the bottle’s upper portion exposed to the sun and the lower portion protruding in the ceiling. The rubber sealant, or epoxy resin, is used to secure the roof sheet and prevent leaks.

The bottle is filled with a solution of purified water, a bit of salt and chlorine measured by three bottle caps.

In the process, the water refracts the light while the chlorine and the salt slow down evaporation and prevent molds. The solution is expected to last up to two years before it needs changing.

Sustainable energy

Environment advocate Illac Diaz, founder of My Shelter Foundation, said Solar Bottle Bulbs are based on the principles of Appropriate Technology, which develops “simple and easily replicable technologies (to) address basic needs in developing countries.”

“It solves two problems—environment and social poverty,” Diaz said at the project’s launch recently.

He said the project would use recycled plastic bottles. Building the device, he said, would cost less than P100.

Some residents reported a sharp decrease in their power bills.

Baby Operanio, 43, said her bills fell from P1,200 to P544 since her family started using the Solar Bottle Bulbs.

San Pedro Vice Mayor Norvic Solidum, whose office is the project’s local partner, said the families were apprehensive at first about having to cut holes on their roofs.

“What I did, I had one on my own roof in our bodega (storage room) and invited the families to see it themselves,” he said.

Diaz, who also uses solar bottles in his own warehouse, said the Solar Bottle Bulbs bring white light.

“You give people light and they would not want to be in the dark again,” said Solidum.