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This Waterless Toilet Could Charge a Cell Phone

Makers of a waterless toilet could soon be setting up their loos in major cities, and they're more than just glorified outhouses; they turn waste into clean-enough water, ash and energy that could be used to charge a cell phone, according to its developer.

The so-called Nano Membrane Toilets have been developed by Cranfield University in England, which received a $710,000 award from the Bill and Melinda Gates Foundation four years ago. Cranfield announced last week that it has received an additional infusion of funds. 


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The toilets consist of two systems. One collects solid waste from the bowl and transports it to a chamber, where a traditional toilet's water tank would be. The waste is burned, creating energy and reducing the solid to ash. Liquid is warmed by heat generated in the tank and then filtered to produce "pure" water, according to Cranfield. It's not clean enough to drink, though.

Major cities will be just be testing grounds for the toilets, which are ultimately expected to make it to urban areas without adequate sanitation systems. The toilets are meant to be used in individual households and can handle waste for about six months before being serviced by a trained technician. Moisture is gathered and converted into water for washing and irrigation, and solids are tuned into ash and energy. Any electricity generated could be used to charge cell phones, according to Cranfield.

The exact business model and deployment strategy for the toilets haven't been made public yet, but the university says households could rent the toilets for less than 5 cents per person per day, assuming a 10-person household.

The funding from the Bill and Melinda Gates foundation was awarded as part of a "Reinvent the Toilet Challenge." The amount money Cranfield received in this second round of funding has not been disclosed.