poo power, renewable energy, wastewater treatment, sewage, sewage 
sludge, fuel cells, microbial fuel cells, nanotechnology
Engineers at Oregon State University have their minds in the gutter. They’re working on getting more energy from sewage, and they’ve made a discovery that boosts electricity production substantially. By applying a nanoparticle coating to the anodes in fuel cells that turn crap into currents, they increased production nearly 20-fold.
In this particular potty-to-plug technology, bacteria from the sewage are placed in an anode chamber, where they consume nutrients and grow while, in the process, releasing electrons. The researchers put a nanoparticle coating on the graphite anodes – one bit of bad news: the coating was gold. Talk about flushing good money down the toilet! However, iron may work nearly as well, at least for certain kinds of bacteria.
Interesting note: OSU’s Hong Liu, an assistant professor of biological and ecological engineering, gained inspiration for the work when changing her young son’s diapers.