A solar-powered commode that treats waste products electrochemically won first prize in the Bill & Melinda Gates Foundation’s competition to design a toilet that can help improve sanitation and curtail waste-borne diseases in the developing world, The Seattle Times and Reuters report.

A California Institute of Technology team was awarded the $100,000 first prize on Tuesday in the foundation’s Reinvent the Toilet Challenge, launched last year to develop alternatives to conventional flush toilets. The world’s largest philanthropy also announced  $3.4-million in new support for such projects, bringing its investment in new toilet technology to $6.5-million.

The Caltech model treats and recycles water for the next flush, and also breaks down feces and urine into hydrogen gas that can be stored in fuel cells for use as a household energy source. British and Canadian researchers received smaller grants for prototype toilets that treat and convert solid waste.

In announcing the prizes, Bill Gates, who with his wife is chairman of the foundation, called sanitation an “ignored” but crucial element in improving health for the poor. Some 2.6 billion people worldwide lack access to toilets, largely for lack of plumbing systems, and 1.5 million children are killed each year by diarrhea-related illnesses.