Earlier this week (August 14), the Reinvent the Toilet Challenge announced its first prize winner: a solar-powered toilet that generates hydrogen and electricity from flushed human waste.
The Challenge, posed by the Bill & Melinda Gates Foundation, calls for researchers to come up with novel ways of disposing of human waste that avoid the drawbacks of the traditional flush toilet, including dumping high volumes of clean water and wasting the nutrients and energy found in urine and feces. In total, the Challenge’s contestants, each demonstrating their inexpensive (less than 5 cents per user per day) and productive (recovering salt, water, nutrients, and energy) human waste disposal prototypes, processed some 50 gallons of soy-based synthetic feces.
The solar-powered winner was developed by Michael Hoffmann of the California Institute of Technology and colleagues, and uses an electrochemical reactor to convert human waste into hydrogen gas that can be stored to power the ...
