Urine: Fuel of the Future?

urinating-statueThis morning I spotted an interesting post in my Facebook feed about a group of Nigerian school girls who  had invented a generator that uses urine as fuel. According to this article on Forbes.com the generator uses one liter of fuel to provide 6 hours of electricity. This could have an amazing effect on a continent like Africa where electricity infrastructure is often non-existent, and where it does exist it tends to work badly.

Now, this sounds great and at first glance it would seem that these girls have really discovered something interesting. But all you have to do is think about it a little bit and you will see that this is actually not all it’s cracked up to be.

First of all, the article I posted is from November 2012. That raises a red flag in my head because if something with this kind of  potential to uplift people’s lives were legitimate, you’d have seen more of it by now. There would be prototypes and public information campaigns. People would be spreading the news like they do with the solar powered oven and wind-up radio.

But the real problem with this story is the very first step in the urine-electricity generation process:

Urine is put into an electrolytic cell, which separates out the hydrogen.

An electrolytic cell.

Electrolysis.

Using electricity to create an otherwise non-spontaneous chemical reaction.

And right there the urine powered generator falls over like a tripod with two legs. What’s happening is they are using electricity to create electricity.

Because nature runs on laws, in this case we will apply the law of conservation of energy. No system can create more energy than it consumes. At best these young ladies have found a way to use electricity to make less electricity.

I applaud them for their ingenuity, and hope that they will go on to create truly exciting inventions that revolutionise the lives of the poor. This, however, is not it.

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12 responses to “Urine: Fuel of the Future?

  1. dear author
    I don’t know have you ever heard of solar electricity or not!
    this is not only about making electricity from electricity, here these girls are making usable electricity from natural day light electricity. Which is cost affective and nature friendly too!
    And yes you were right in your last paragraph ,there work is applaudable!

  2. Would a litre of water (urine) provide enough hydrogen to run a generator for 6 hours? Would hydrogen evolve sufficiently quickly – I’m doubtful! Hydrogen isn’t especially energy dense – suspect the only way you could get enough energy from a litre of piss would be if you’d cracked cold fusion!

    • what’s the point? – if you are generating electricity from a solar cell there’s not much point in using it to crack the hydrogen in urine – you might as well use it directly

  3. Added this to rbutr, because the urine for energy thing has been doing the rounds just a little too much. Important to have these rebuttals linked.

  4. The apparent fact that they’re using urine is a red herring? It’s probably the water (obviously 99% of urine) that’s supplying hydrogen?

  5. I remember seeing this a few years back, and immediately realised the problem of needing electricity for the electrolysis process. You could use one of the many renewable sources for the electricity, but then why convert urine? Use urine for what it is good for – fertiliser and disinfectant, or just flush it away with vast amounts of fresh water.

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