Editorial Feature

What is Gravity Light?

How Does it Work?
Benefits of Gravity Light
Gravity Light vs Solar-Powered Light


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.

How Does it Work?

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.

what is gravity light

Image Credit: YouTube

Benefits of Gravity Light

The key benefits of gravity light include the following:

  • It is inexpensive
  • It has no operating costs
  • It does not requires any batteries
  • It can power radios, reading lights and other small electrical devices
  • It can recharge batteries.

Gravity Light vs Solar-Powered Light

It is a common belief that with the improvement in technology, solar-powered lighting is offering a more sustainable alternative across the globe. Solar panels are capable of producing electricity only when the sun shines and hence the energy is required to be stored for producing light under dark conditions. The quantity of energy stored is based on the size of storage, size of the panel and the amount of light energy absorbed from the sun.

Solar lights, panels and batteries are expensive and not affordable for a lot of people let alone for developing countries. Although solar lighting projects continue to be carried out by several millions of people in the developing world, their spread is very slow as individual homes cannot afford them. Hence only installed by the communities.

With gravity light, it takes very few seconds to create enough energy to provide lighting for half an hour as required by simply lifting the weight. It is clean and environmentally-friendly. As gravity light does not have any operating costs after the initial purchase cost, it is more suitable for individuals with no big savings. Therefore, this could provide sustainable lighting for developing countries and replace the harmful kerosene lamps that are currently being used in these types of countries.


Electric lighting can be easily taken for granted. Millions of people in the developing countries do not have the luxury of electricity and depend on kerosene lamps. Kerosene is expensive and inhaling the fumes of kerosene is dangerous. An inexpensive renewable and sustainable gravity-powered light could indeed be an appropriate solution for lighting demands across the world.

The gravity light has now captured a lot of public interest. The developers have been seeking crowd funding to raise capital for the manufacturing of gravity lights, and they have raised more than $115,000, blowing away their initial $55,000 goal. They aimed at selling the light for as low as $5 on mass production thus making the light pay for itself within a couple of months from the savings of not having the need to purchase kerosene.

This light may also find applications as a camping light or an emergency light in the future, but for now the gravity light is an example of something that just seems like the basic science of gravity, but is, and can be so much more to people around the world. Being able to supply lights that have no running cost for $5 is an incredible feat and one which could help the lives of millions of people seeking sustainable light at low cost.

GravityLight: Lighting a billion people - Run Time - 2:26mins

GravityLight: lighting for a billion people


Kris Walker

Written by

Kris Walker

Kris has a BA(hons) in Media & Performance from the University of Salford. Aside from overseeing the editorial and video teams, Kris can be found in far flung corners of the world capturing the story behind the science on behalf of our clients. Outside of work, Kris is finally seeing a return on 25 years of hurt supporting Manchester City.


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  1. Mayur Kale Mayur Kale Canada says:


    this is amazing. Where can I order the GravityLight?

  2. Kenny Stage Bishop Kenny Stage Bishop United States says:

    This needs to be world wide. We all need to be using this device. Think of all the savings....for all of us!

  3. Harsha Harsha Harsha Harsha India says:

    superb it  is  very help full for people who  are living in remote areas.
    i  do have some doubts, what are  the  main components  used in  this gravity light  and  how does the small rotation gives that much of light intensity.

    • mujeeb mhammad mujeeb mhammad India says:

      its about gear ratio and its LED can glow at low speed .....thanks to the inventor for this valuable product

  4. Jack Strawb Jack Strawb United States says:

    The GravityLight has all but disappeared from the conversation on clean energy. It has ostensibly been replaced by the NowLight, but there's little in the news about getting the NowLight to developing countries.

    Why has this extraordinary invention all but disappeared from view?

The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of AZoCleantech.com.

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