Where There Is Gravity, Let There Be Light

By the dim glow of a kerosene lamp, a family in Kenya settle in for the evening. Huddled around a communal table, the children diligently do homework while the adults perform a myriad of household chores in the gloomy half-light. It’s a fairly typical scene played out across the world, with nearly 2 billion people living without access to electricity. For these, light is not something to be taken for granted: the kerosene that fuels most off-grid lamps is very expensive, perhaps 20% of a person’s income, and to buy it often involves an arduous walk of many miles. But more than this, kerosene is also dirty and dangerous. Quite apart from causing millions of severe burns every year, kerosene lamps fill homes with toxic fumes and smoke.

It begs the question, is there a better way? Shell is committed to helping find exciting and innovative new ways to harness and generate energy. Their #makethefuture campaign promotes the power of people’s ingenuity to answer energy challenges, and with GravityLight they have found an answer to the question of kerosene: a way to turn the kinetic energy of a slowly descending weight into the electricity to power an LED lamp. GravityLight is one of six energy start-ups awarded funding to develop ground-breaking concepts, a testament to Shell’s belief that it only takes one idea to change the world. This idea is already making a difference.

In 2009 British designers Martin Riddiford and Jim Reeves were challenged to create a safe, affordable, and sustainable lamps for low-income families living off-grid. Looking beyond solar and battery power, they had a lightbulb moment about gravity. Lifting a weight creates a potential energy store which is turned into kinetic energy as the weight descends. Through the GravityLight’s innovative gear train, this kinetic energy spins a generator that produces enough electrical energy to power an LED bulb. When the light goes out, the weight is simply hoisted back up to begin again.

Although simple in principle, the GravityLight is very carefully engineered, using special polymers, great geometric detail, and other innovative design features to ensure a smooth and constant output of power. It even allows you to add multiple lights, turning these on and off independently.

With the help of Shell, GravityLight has been piloted in Kenya where kerosene lamps are used extensively, especially in rural areas. A 50-night roadshow, supported by International celebrities, saw GravityLight engage with communities and organizations across the country. The results were impressive, with 90% of people saying they were happy to switch from kerosene. Little wonder, as the benefits quickly stack up. The GravityLight pays for itself in just seven weeks, and delivers an immediate improvement in the air quality of the home. It is clean, robust, renewable, reliable, and safe—as well as being better for the environment, giving off no CO2 or black carbon emissions.

Building on the insights from their pilot and sales worldwide, the design team behind GravityLight is continuing to iterate and improve. They are currently working on a solution that provides significantly more power, including the ability to charge mobile phones, addressing the needs of off-grid households as well as helping prepare and respond to emergencies. This will be launched in 2018 and, building on the lessons and success of GravityLight, will be rolled out internationally in an effort to reach everyone living without electricity. For Shell, GravityLight really is a shining example of how ideas can change the world.