Guest essay by Eric Worrall
What could be better for providing light in a poor country with no electricity than a cheap kerosene lamp? A group of renewable entrepreneurs think they have found the answer – meet Gravity Light, a third world LED lighting system powered by lifting a bag containing 12Kg (27lb) of rocks every 20 minutes.
GravityLight Brings Clean Energy to Kenya
In Kenya it’s estimated that one in seven people live without access to electricity. Sixty eight percent of Kenyans rely on kerosene as their main source of energy. Kerosene is expensive as a fuel, and can be dangerous as a flammable in the household. GravityLight is one of several startup companies working to make clean and renewable energy and lighting available to families in Kenya and around the world. The foundation has partnered with Shell to send more than 3,000 lights to families in Kenya.
The light isn’t very bright. According to the specification;
|Product weight (empty bag)||1.2 kg / 2.6 lbs|
|Max loaded bag weight||12.5 kg / 27.5 lbs|
|Nominal Voltage||2.7 V DC|
|Max current||<0.031 A|
|Max electrical power||0.085 W|
|Luminous flux||15 lm|
|Luminous efficiency||208 lm/W|
|Colour temperature||5000 K|
|Colour Rendering Index||> 70|
Read more: Specification Document
But hey, the idea has an endorsement from Bill Gates. And think of the health benefits. Instead of studying for hours by the steady flame of a kerosene lamp, risking DVT from all that sitting down, every 20 minutes someone has to winch up a heavy bag of rocks.
Perhaps the benefits will spread to first world countries. Who needs an industrial economy and a steady supply of fossil fuel powered electricity, when you can have the healthy exercise benefits of owning a human powered gravity light?