Bright ideas

‘A Litre of Light’ solar bottle

Waste plastic water bottles used for harnessing sunlight for poverty-stricken homes in the Philippines

The idea
‘A Litre of Light’ (‘Isang Litrong Liwanag’) is a sustainable lighting project using discarded plastic bottles, which aims to bring a sustainable solar bulb to low-income communities.

The idea was designed and developed by students from the Massachusetts Institute of Technology (MIT) and implemented by MyShelter Foundation. The product is based on the principles of Appropriate Technologies – a concept that provides simple and easily replicable technologies that address basic needs in developing communities.

The need
There is an ongoing problem of access to light and legal electricity throughout the Philippines in many urban and rural areas. Small, crowded communities are often covered in darkness even during the day because of the lack of ambient light. Using electricity during the day, as well as at night, raises household expenses by around 40%, which makes a significant impact on the low income population where 32.9% of people live below the poverty line (2006 est).

The product
The solar light bulb is made from used water and soft drink PET bottles. The discarded bottles are recovered, cleaned and filled with a solution of water, chlorine and salt, which prevents bacteria growth and discoloration. The bottles are then fitted into the corrugated sheet roofs of the community dwellings, leaving the top half of the bottle exposed to the sunlight above the roof line, and the bottom half of the bottle exposed in the room below.
Due to the powers of refraction, sunlight is diffused into the rooms, providing a cheap and sustainable source of light.

Future objectives
The project began with lighting 10,000 solar bulbs in the City of San Pedro, Laguna and has a vision of lighting a million homes by the end of 2012.

Apart from the actual number of installations, this project also aims to empower individual citizens to take a step towards using sustainable energy, whether by the use of the solar bottle bulb; volunteering in the project implementation; or being inspired to come up with their own ideas.

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