Venture Beat reports: [edited]
Two designers in London have built functioning prototypes of GravityLight, a cheap way for people in developing countries to light homes, recharge batteries, or power a radio. And they just exceeded their Indiegogo fundraising goal by more than 500 percent with 21 days left in their campaign, so they’ll have the resources to mass-produce the light for less than $5 a unit.
Using the GravityLight simply requires removing the small white lamp from its bag, hanging it up, filling the bag with about 20 pounds of dirt or rocks, and attaching the bag to bottom of the device. Gravity powers a generator, light fills your room, and every 30 minutes, you hoist the bag back up.
The goal is to provide clean, efficient light for the 1.5 billion human beings on this planet who still do not have reliable access to electricity and use kerosene-powered lamps.
According to Riddiford and Reeves, the use of kerosene results in vastly higher cancer rates due to smoke inhalation, and 2.5 million burn victims due to dropped or jostled lamps every year in India alone. Not to mention the cost: 10 percent to 20 percent of a household’s income in the developing world can go to fuel for lighting.