Whether or not you put much faith in groundhog predictions, one satisfying sign that winter is finally releasing its icy grip is the subtle, yet steady, increase in daylight hours. Many North Americans agree it is the bleak darkness of winter that is hardest to endure. Fortunately, with just the flip of a switch, we are able to able to carry on daily activities well into the evening hours, regardless of time of year or which charming rodent has seen his shadow.


The price of power leaves many in the dark:  Looking for Alternative Lighting Options in Developing Countries.

Electric light is something we largely take for granted and, as such, it may be surprising to learn that one in five – that is, more than one billion people – live without electricity. For these people, carrying on daily functions once the sun sets means settling for less than ideal options, such as kerosene lamps, to light the way. As a fuel, kerosene is expensive and dangerous.

Research has found that, for some of the world’s poorest, up 30% of their monthly income is spent on kerosene fuel, which is highly flammable and emits toxic fumes. The challenge of replacing kerosene with an affordable, sustainable energy source that is as reliable as the rising and setting of the sun is challenging, but not impossible.

Light: At the speed of gravity

Possibly inspired by the forces behind the sun itself, finalists from Shell’s 2015 Springboard Awards channeled the energy potential behind ‘what goes up, must come down,’ in their innovative design, which combines kinetic and potential energy as a source of power for free light.

GravityLight generates light from gravity, which means it doesn’t require batteries or sunlight and can be used anywhere, at any time. The design is simple: An elevated weight – essentially a bag filled with sand or rocks – is connected to a pulley system; this is even better than other alternative lighting sources in developing countries, which usually rely on the sun or water to generate power.

Using gravity, the weight slowly drops (about 1 mm per second) and this movement powers a drive sprocket, which rotates very slowly with high torque. A polymer gear train running through the product turns this input into a high speed, low torque output that drives a DC generator at thousands of rotations per minute.

LEDs translate a few watts into lots of light

This process generates just less than a deciwatt (on tenth of a watt), which can power an onboard LED and ancillary devices, such as SatLights. Because LEDs are so efficient, the light produced by the GravityLight is over five times brighter than a typical open-wick kerosene lamp. Once the weighted bag reaches the floor, the process is repeated simply by lifting the bag back up to the top of the pulley system.

Investing in R&D led to updated design and new applications

The team used funds raised through a very successful crowdfunding campaign to manufacture and distribute over 1000 lights, which were given to off-grid families in Africa and Asia. These families were then able to provide extremely valuable feedback, which, along with the Shell Springboard prize of £150,000, helped shape essential modifications and improvements to the device. The updated design (GL02) will be assembled in Kenya, thus creating jobs and skills in regions where opportunities are relatively scarce.

Interested in supporting the GravityLight journey?

With a revised design in hand, along with the recent bump in funding, the team hopes to start production on its Kenyan assembly line in the spring of 2016. GravityLight also aims to expand its market to include disaster relief organizations and refugee camps. The Indiegogo crowdfunding campaign is still active, with funds going towards the Made in Africa initiative, supporting the setup of operations in Kenya with materials like soldering irons, assembly jigs, and quality testing equipment, as well as staff training on assembling GravityLight and performing QC and QA checks.

In addition to supporting a great cause, the GravityLight is a pretty cool, yet highly practical product. For $70, supporters will receive one the first samples of the new, Made in Africa, GL02 and 2 SatLights (estimated delivery September 2016). It’s a great lighting alternative for camping and a helpful addition to your emergency response kit. Or, for the Isaac Newton enthusiast, it is also a really neat homage to the law of universal gravitation.

While we may still be at the mercy of nature when it comes to changing seasons and hours of daylight, it is inspiring to see how simple, elegant solutions arise when human invention and the forces that be come together to do something good.

About The Author

John Keirstead
John Keirstead
Serial Entrepreneur, Technologist and Inventor my objective is to develop useful products that have a net positive effect in the lives of those that use them and the environment that we live in. CEO of Mission LED Lighting Company Ltd.

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