There aren't any batteries or fuel in the $5 revolutionary lamp called the GravityLight.

The ultra-cheap lamp was created as a replacement for expensive and highly polluting kerosene-powered lanterns, which are widely used in developing countries. London-based designers Martin Riddiford and Jim Reeves have been working on the GravityLight as a side project for the four years.

For the 1.5 billion people in the world who live off the electric grid, homemade kerosene lamps are the norm. But, the kerosene can eat up 10% to 20% of a family's household income, according to the designers. Fueling these lamps with kerosene is also extremely dangerous. Men, women and children are regularly exposed to fire hazards and harmful fumes produced by the burning kerosene.

There are no operating costs after the initial purchase of the radical GravityLight lamp. Each GravityLight kit will come with the adjustable lamp and ballast bag. Once the bag is filled up with sand, rocks or soil, users can hang it from the lamp like a weight to turn the LED bulb on. This creates enough energy to last 30 minutes whenever it's needed. The lamp can be recharged by solar panel.

SEE ALSO: Ultra-Cheap Android Tablet Comes to India

With this revolutionary lamp, the GravityLight will have no running cost and will allow families in developing countries to live kerosene-free.

Meeting their Indiegogo goal will allow the designers to increase production units making the future market price even cheaper. The GravityLight project has raised more than $190,000 dollars with 27 days left on the crowdsourcing platform Indiegogo.

Thumbnail image courtesy of Flickr, babbagecabbage; Main image courtesy of Indiegogo, GravityLight