Developed by two London-based designers at innovation company Therefore, the GravityLight produces 30 minutes of light for three seconds of effort. With an estimated market price of $5, families can expect to see a payback period of just three months, in terms of the savings on kerosene expenditure.
To power GravityLight, the user pulls a rope, which lifts an attached bag, weighted with 9kg of materials. Gravity does the rest. As the bag descends, a series of gears translate the weight into energy, powering a small generator. The project is aptly named Deciwatt, after the amount of power the GravityLight produces. A deciwatt is enough to power an LED light and some small devices, such as a radio, or to charge batteries.
After developing and self-funding GravityLight for four years, the team behind Deciwatt turned to the crowd-funding site indiegogo. After raising $399,000, they will now be piloting 1,000 GravityLights in remote communities over three continents during 2013. Mike Pepler, UK Ashden Awards Manager, believes it has “huge potential”, but adds that the “durability of the gearbox will be key, as will getting sufficient light output”.
Jim Fullalove, Therefore’s Director, says that “it has to be designed to work many times over, and be useful and practical”. If, by the end of 2013, it proves to be all of this, he adds – and users really want it, “then of course there is no reason for it not to go into volume. It could be a product to break the poverty trap” by sparing families hefty kerosene costs. While the GravityLight is being trialled, says co-designer Martin Riddiford, the team will be “setting [its] sights high” by researching the possibility of a battery-free system for accessing the internet.– Olivia James