Gravity-Powered LED Lights Are Lighting Up Third-World Countries
According to core77.com, "Roughly 25% of the world's population have no access to electricity. In these areas using kerosene lamps for lighting is common. The potential for fires and burns from these lamps are bad, but the persistent fumes are worse. One study has it that the women tending these lamps sustain lung damage equal to smoking two packs a day, saddling many of these women with lung cancer. And of course, there are children around these things too.
A nonprofit called SolarAid approached London-based product designers Jim Reeves and Martin Riddiford, asking them to design a solar-powered light source to alleviate the problem. In order to be cost-effective for developing nations, the lamp would have to cost just six dollars."
This is what they came up with....