GravityLight is a revolutionary new approach to storing energy and creating illumination. It takes only 3 seconds to lift the weight which powers GravityLight, creating 30 minutes of light on its descent. For free.
Following the initial inspiration of using gravity, and years of perspiration, we have refined the design and it is now ready for production. We need your help to fund the tooling, manufacture and distribution of at least 1000 gravity powered lights. We will gift them to villagers in both Africa and India to use regularly. The follow-up research will tell us how well the lights met their needs, and enable us to refine the design for a more efficient MK2 version. Once we have proved the design, we will be looking to link with NGOs and partners to distribute it as widely as possible. When mass produced the target cost for this light is less than $5.
In some parts of the world, lighting is provided through expensive and polluting kerosene. Kerosene lamps are hazardous to health and environment and constantly require replenishment. Fumes which are raised from the burning of biomass fuels can cause cataracts and eye infections as well as emitting smoke that is the equivalent to smoking two packets of cigarettes everyday.
Also, it was estimated that nearly 2.5 million people in India alone suffer severe burns from overturned kerosene lamps every year as well as the vast amounts of carbon dioxide produced.
London based designers, Martin Riddiford and Jim Reeves, have spent around four years working on an inexpensive and safe alternative that will be of great benefit to many people across the globe – a gravity-powered LED light. Unlike solar-powered lamps, the gravity light can be operated all the day and night and under any climatic conditions with zero running costs.
GravityLight is powered by the lift of a weight.
As the weight falls it turns a gear train, driving the motor that powers the LEDs.
GravityLight doesn’t need batteries or sunlight and costs nothing to run. It takes seconds to lift the weight that powers GravityLight, creating 20 minutes of light on its descent.
GravityLight is installed to provide a 6ft/ 1.8m drop of a 12kg weight. This weight is lifted by a person pulling the orange cord. A pulley system means the weight only feels like 3kg. Once lifted, the weight then falls very slowly (about 1mm / second).
This movement powers a drive sprocket, which rotates very slowly with high torque (turning force). A polymer gear train running through the product turns this input into a high-speed, low-torque output that drives a DC generator at 1600 rotations per minute.
This generates about a tenth of a watt to power the onboard LED and two SatLight LEDs. Together these produce a light more than 5 times brighter than a typical open-wick kerosene lamp.
Once the weighted bag reaches the floor (after 20 minutes), it is simply lifted to repeat the process.
How it Works ?
The gravity light consists of an LED bulb fixed to an adjustable lamp that can be hooked up on a wall or hung from a ceiling. It also comprises a pulley mechanism and a ballast bag hanging from the lamp. The ballast bag is filled with up to 9 kg of rock, sand or soil. The gravity light works on the principle similar to that of pendulum clocks that are operated with the help of weights. The potential energy is represented by the ballast material.
When the ballast bag is suspended, the potential energy in the ballast is converted by gravity with a slow descent of the bag. The converted energy then generates light. The gravity light can be operated for 30 mins continuously before the ballast bag needs to be refilled. The strength of the light can be adjusted from strong lighting to long-lasting low-level lighting. The two terminals present at the front of the gravity light can be used as a generator.
The Benefits Of GravityLight
- + Instant light, any time
- + No running costs
- + No sun or batteries needed
- + Robust and reliable
Smarter Every Day
Destin Sandlin is an aerospace and mechanical engineer from Alabama. He’s also the brains behind Smarter Every Day, a YouTube channel with over 4 million subscribers. As anyone who watch’s Destin’s videos will testify, he likes to explore and explain the world through science – helping his viewers become, well, smarter every day.
So naturally we thought he’d be the perfect person to pull apart a GravityLight and share his opinions on the impact this bright energy idea will have on developing nations. Watch the video below to grow a little smarter.
Why Gravity Light?
Did you know that there are currently over 1.5 billion people in the World who have no reliable access to mains electricity? These people rely, instead, on biomass fuels (mostly kerosene) for lighting once the sun goes down.
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.
The burning of Kerosene for lighting also produces 244 million tonnes of Carbon Dioxide annually.
Light without kerosene
Kerosene is a widely-available fuel used throughout the world. It can however be a costly and dangerous source of energy. Studies show that kerosene expenses can consume up to 30% of the monthly income for some of the world’s poorest families. Worst yet, open kerosene flames are common causes for burn trauma and the destruction of homes. Much like cigarette smoke, the fumes from gas lamps may also contribute to cancer.
GravityLight helps break the poverty cycle as it pays itself off thereby replacing a dependence on kerosene. The light empowers children and adults as it gives them a safer and healthier way to study at night. And because GravityLight uses local distribution partners and sales agents Kenyans can even earn a living selling the products. We believe this is a bright energy idea that just keeps on giving.