GRAVITYLIGHT - ALL YOU NEED IS A WEIGHT
Created to empower 1.5 billion people that live off the grid, and to battle the hazardous effect of what is often still the only source of lighting, kerosene, GravityLight stands for an entirely new way of generating light, exploiting gravity.
About 20% of the world's population - have no reliable access to electricity. In many countries, the grid is also failing to keep pace with population growth, which means that the number of people without reliable electricity source will continue to grow. Most often, these people rely instead on biomass fuels - predominantly kerosene - for light. Yet kerosene lamps are extremely inefficient, dangerous and expensive, and have extensive health and environmental drawbacks.
In 2009, Therefore design consultancy, which also developed the famous Psion hardware, was approached by SolarAid to develop an extremely low-cost solar light for off-grid families that have to live on less than $3 a day. After realising that batteries and photovoltaic (PV) panels were two thirds of the cost, designers Martin Riddiford and Jim Reeves decided to look beyond solar and battery-powered devices.This led to the invention of GravityLight – a first of its kind. The light works by connecting an elevated weight — a bag filled with rocks, sand or whatever — to a pulley system that slowly powers a generator as the weight returns to the ground. As the weight falls it turns a gear train, driving the motor that powers some LEDs.
It takes just a few seconds to lift the 12 kilo weight that powers GravityLight, providing 20 minutes of light as it descends. Due to the pulley system, the weight only feels like 3kg. There's no sunlight or batteries needed, which means that GravityLight can be stored indefinitely, and doesn't have to charged in advance. The light is ready when you need it. As the energy generated from the device is completely self sustained, without any running costs, GravityLight pays for itself within months of switching from a kerosene lamp.
obust and reliable, the GraviLight also produces a light over five times brighter than a typical open-wick kerosene lamp, After the designers had a working prototype ready by the end of 2012, a first crowdfunding campaign allowed field tests across 26 different countries, and the development of an improved model, GravityLight GL02 - easier to use, brighter, and more robust .Another crowdfunding campaign in 2015 enabled to launch and pilot the improved product in Kenya - including testing assembly of the units on the spot. Rather than undermining the already extremely fragile local economy by flooding the maket with free products, the GravityLight Foundation works through sales agents and community networks: „We aim to create local jobs, skills and livelihoods in the heart of the communities that will be using it“.
The cost of the GravityLight will depend on whether it is sold in the developing or developed world. In the U.K., for example, it is set to sell for £49 ($63), while in Kenya it would cost roughly 2,500 shillings ($24.70). At the conclusion of the Kenya pilot, the foundation dreams of scaling up GravityLight internationally to reach the 1.2 billion people living without electricity. And meanwhile, the team is also investigating using the GravityLight technology to power other devices, such as a radio or mobiles, and to charge batteries The ultimate goal is to establish how small amounts of constant power can be utilized to provide low cost access to the internet, from very remote locations, at incredibly low cost’. (mb)