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10 surprisingly easy sources of alternative energy

By: Bryan Nelson on Nov. 30, 2009, 11:27 a.m.
Human sewage

Photo: forbescreative/Flickr

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Human sewage

Poo power? Even human sewage can be used to create electricity or fuel. Plans are already underway to power public buses in Oslo, Norway, with human sewage. Electricity can also be generated from sewage using microbial fuel cells, which utilize a bio-electrochemical system that drives a current by mimicking bacterial interactions found in nature. Of course, sewage can also be put to use as a fertilizer.