A revolutionary waterless toilet powered by the sun, developed to help some of the 2.5 billion people lacking safe and sustainable sanitation around the world, will be unveiled in India this month.

Designed and built using a $777,000 grant from the Bill & Melinda Gates Foundation, the self-contained, waterless toilet with its innovative technology converts human waste to biochar, a highly porous charcoal. It aims to provide an eco-friendly solution to help some of the 2.5 billion people around the world lacking safe sanitation.

The toilet has the capability of heating human waste to a high enough temperature to sterilise it and create biochar, a highly porous charcoal, said Karl Linden, project principal investigator and professor at the University of Colorado. The biochar has a one-two punch in that it can be used to both increase crop yields and sequester carbon dioxide, a greenhouse gas.

The project is part of the Gates Foundation’s “Reinvent the Toilet Challenge,” an effort to develop a next-generation toilet that can be used to disinfect liquid and solid waste while generating useful end products, both in developing and developed nations, said Mr. Linden.

While the current toilet has been created to serve four to six people a day, a larger facility that could serve several households simultaneously is under design.