Kerosene lamps, used by more than one-quarter of the world’s population, makes people susceptible to inhaling high levels of particulates (a mixture of extremely small particles and liquid droplets) and have 9.4 times chance of inducing Tuberculosis. Two London-based designers, Martin Riddiford and Jim Reeves worked on GravityLight, a lamp powered by gravity that is available at a cost of less than $5, thereby having the potential to bring light to remote regions in developing countries.
There have been several innovations in the sphere of bringing low cost lighting to developing countries, from solar-powered lamps to wind-up devices and batteries that are rechargeable; all of these have kits that are expensive or require humongous efforts by the end user. GravityLight, by contrast, is simple and inexpensive.
GravityLight uses a bag filled with rocks or stones attached to a cord, which slowly descends depending on the weight of the rocks; this particular action powers light for more than 30 minutes. After the purchase of the lamp, there are no other running costs involved.
A standard kit from GravityLight contains an adjustable lamp and a ballast bag (to provide stability). The light can be turned on by filling the bag with approximately 10 kg of rocks or stones and lifting it up to the base of the device, when the bag falls over a period of 25 minutes, the strap spins gears and drives a motor that powers an LED (The time of 25 minutes is an approx number that was derived after trials for 8-10 kg of rocks or stones in the bag. The action of gravity is what drives the motor generating power for the LED). The lamp can also be recharged by a solar panel. Three seconds of lifting the weight up generates more than 30 minutes of light.
The initial idea was met with skepticism by traditional financiers who asked if people would be able to afford the $10 upfront cost (it was brought down to $5) or would they really lift a weight. Collection of field data also meant the founders needed to empty their pockets for the project, so they eventually turned to crowdfunding to raise $55,000. Exceeding expectations, by the time the campaign had ended in 36 days, they had raised as much as $3,99,550 from individuals and organisations, including governments.
The project emerged thanks to a competition held by the charity SolarAid, which had asked participants to come up with a low-cost light source as an alternative to the harmful kerosene lamps used in developing countries.
In an interview to wired.co.uk, Reeves says, “The investment made by the villagers is returned within three months of being freed from the cost of kerosene. After that, the entire money goes as savings”. The light strength can be adjusted, so the glow can be extended for a long time.
GravityLight, produced by the duo’s company Deciwatt.org, aims to provide affordable light to 1.5 billion people who don’t have access to reliable electricity. The duo worked with therefore.com where they were engaged with solar projects, but were developing GravityLight as a side project too. The team has plans for the device to charge batteries or power other small devices as a feature that comes along with the light feature.
“With hand-cranked devices, it might take about three minutes to turn the handle for a half-hour use. If such a huge effort is required, then the consumer might not consider it an attractive trade-off, but GravityLight needs only three seconds of lifting for a 30 minute return,” Riddiford told The Guardian.
GravityLight has the potential to lift people out of poverty, allowing them to use the saved money for other household expenses and lead a better life.
— mathew.maniamkott@gmail.com