Bill Gates' Latest Tech Development: Turning Crap Into Resources (Literally)

The flush toilet so many of us know so well is in fact out-dated technology. That, and the fact that they are “are irrelevant, impractical and impossible for 40 per cent of the global population, because they often don't have access to water, sewers, electricity and sewage treatment systems" is why Bill Gates has offered up cash for their re-invention.

To enter into the competition, all prototype toilets needed to operate without running water, electricity or a septic system; must not discharge pollutants; and cost no more than five US cents a day to run.

The big winner, designed by a team at the California Institute of Technolgy, uses solar power to run an electrochemical reactor that disinfects human waste, leaving a by-product of chlorinated water (to be used for the next flush), hydrogen (sent to a battery for when there’s not enough solar power) and fertilizer. The team displays and explains the toilet here.

Skeptics say that such a high-tech toilet is not likely to proliferate in places where people can’t afford running water, but the world’s wealthy stand to improve their sewage treatment, too. Canadian cities flush some 200 billion liters of raw sewage into oceans and waterways every year.