The Gravity Light

This is a wonderful, ingenious idea.  About 20% of the world's population - 1.5 billion people - still rely on kerosene lamps for light after dark...either that, or they don't have any light at all at night.

There is a great unmet need for a very cheap source of artificial light that can be deployed around the world, ending the dependence on kerosene by those in the poorest places.

A press release from the London-based Gravity light inventors, Martin Riddiford and Jim Reeves, provides teh following perspective...The World Bank estimates that, as a result, 780 million women and children inhale smoke which is equivalent to smoking 2 packets of cigarettes every day. 60% of adult, female lung-cancer victims in developing nations are non-smokers. The fumes also cause eye infections and cataracts, but burning kerosene is also more immediately dangerous: 2.5 million people a year, in India alone, suffer severe burns from overturned kerosene lamps. Burning Kerosene also comes with a financial burden: kerosene for lighting ALONE can consume 10 to 20% of a household's income. This burden traps people in a permanent state of subsistence living, buying cupfuls of fuel for their daily needs, as and when they can.  Moreover, the burning of Kerosene for lighting also produces 244 million tonnes of Carbon Dioxide annually.

It was thought that maybe some sort of solar powered solution could meet this need for a safe, clean, and cheap alternative to kerosene lamps.  Problem with solar is, it requires sunlight. It that sunlight is going to be useful at night, a battery is required to store the energy collected during the day by solar PV cells. 

The gravity light does not depend on solar energy. It is a  LED that is powered by - you guessed it - gravity.

The grivity light

Here's how it works. A weight of about 20 pounds is hung from a string. As the weight pulls the string through the light, it turns a small generator inside the unit that produces enough power to run the light.  One setting of the weight provides about 20 minutes of light before the weight needs to be reset.

Riddiford and Reeves, the developers of the Gravity Light, expect to be able to mass produce them for about $5 each.  That means a subsistence farmer in Africa currenlty using a kerosene lamp can buy a gravity light for about the cost of three months worth of kerosene.   This is a no brainer. This technology should be adopted and dispersed on a mass scale as soon as possible.


Here is a video that tells the stlory of the Gravity Light...  http://vimeo.com/53588182