[Image above] Microbial fuel cells made of ceramic materials meet urine, resulting in an electrical output strong enough to power your smartphone. Credit: University of the West of England
This is one of those times.
Scientists at the Bristol Robotics Laboratory (BRL) in the United Kingdom are hoping to transform one of the world’s most abundant and accessible resources—urine—into electricity.
That’s right. Urine (which isn’t nearly as sterile as people believe it to be).
The same stuff NASA is transforming into drinking water could not only someday power your smartphone or tablet, but could also help to solve many of the world’s renewable energy and sanitation problems.
According to a report from The Economist, BRL researchers have been putting their “urine-tricity” to the test, and have found that their pee power can put off more power than other waste products—three times as much.
How’d they do it?
Urine-tricity is fueled by microbial fuel cells (MFCs) made from ceramic materials.
“When urine flows through an MFC, the microbes consume it as part of their normal metabolic process,” reports The Economist. “This, in turn, frees electrons. Electrodes within the cell gather these electrons and, when they are connected to an external circuit, a current is generated.”
Instead of feeding the MFCs scraps of food, dead insects, or grass clippings, the team, led by Ioannis Ieropoulos, provided a steady stream of fresh urine—which has a lower level of organic carbon, “favourable” acidity, and the ability to conduct electricity—to stacks of the MFCs. The electricity produced by the stacks had an output three times higher than that of the other organic wastes. In the video below, Ieropoulos and company demonstrate pee’s power by charging a mobile phone on the urine-fed MFCs.
Credit: UWE Bristol
The team’s findings were published in Physical Chemistry Chemical Physics last year, and the work at BRL, which is a joint venture between the University of Bristol and the University of the West of England, is being funded by the Bill and Melinda Gates Foundation.
It’s still too soon to say whether pee power will be widely accepted, but with an estimated 6.4 trillion liters of it produced each year, there’s no doubt that urine’s ubiquity lends itself to further exploration.
The paper is “Waste to real energy: The first MFC powered mobile phone,” (DOI: 10.1039/C3CP52889H).