Saw this pop up on reddit – Four teenagers in Africa invent a Urine powered generator and a BBC article with a picture but no description.
Now on the face of it it ticks a lot of boxes – developing nation ingenuity, young kids sticking it to the energy companies and the green credentials (hey – urine’s a renewable resource right?).
But I’m not so convinced.
The claims is that “1 Liter of urine gives you 6 hours of electricity.”
Wow, 1 Litre of urine and 6 hours of electricity.
The following is on the site explaining it.
The system works like this:
Urine is put into an electrolytic cell, which separates out the hydrogen.
The hydrogen goes into a water filter for purification, which then gets pushed into the gas cylinder.
The gas cylinder pushes hydrogen into a cylinder of liquid borax, which is used to remove the moisture from the hydrogen gas.
This purified hydrogen gas is pushed into the generator.
Along the whole way there are one-way valves for security, but let’s be honest that this is something of an explosive device…
What is in Urine?
Going to that bastion of semi-reliable information (wikipedia) – I find that:
Urine is an aqueous solution of greater than 95% water, with the remaining constituents, in order of decreasing concentration urea 9.3 g/L, chloride 1.87 g/L, sodium 1.17 g/L, potassium 0.750 g/L, creatinine 0.670 g/L and other dissolved ions, inorganic and organic compounds.
Ok, so nearly all water – and 9.3 g/L of urea. Hrmm.. On the face of it and with limited research into the chemical energy in urea – that’s not sounding like something that is likely to power a generator with a 10-40% efficiency (and that’s being very generous with the range).
Let’s take a look at the picture from here.
Now it looks to me like a very daggy looking battery (the “electrolytic cell”), several water filter holders, a modified gas cylinder, some tubing, clamps and a generator. The bit from the generator to the electrics is pretty non-contentious – have seen similar things – a light to provide some load/indicator that energy is getting through and some powerpoints to plug the stuff in you want power to.
The “electrolytic cell”
Can’t really see what’s inside that or how it is filled up with urine etc – but keep in mind it’s got to be well sealed enough to pressurise the gas cylinder via the water filter thing in between. Also curious about the wires leading from it to the generator. What’s up with that?
Have they just hooked up the battery to an inverter perhaps? Surely people will expect the generator to be running while it is powering the lights. Or is it supposed to close the loop on supplying power back to produce hydrogen?
Next in the chain is the first of the water filters. What’s it for? “The hydrogen goes into a water filter for purification, which then gets pushed into the gas cylinder.”
Ok, let’s go with that. First up it has no filter in it. Next up: it’s not pushing liquid through and a “water filter” only makes sense if you’re pushing water through it – I’m not sure what the point of it is – surely the gas would just bubble straight through to the exit? e.g. the liquid in it is irrelevant like blowing into a glass with a straw not in the water – the air doesn’t magically go down into the water – it just stays at the top. If you filled it to the top you might get a bit of water blown out initially but then it would have cleared a path. If it had a hose down it you’d get a sheeha/bong type result – but how it is currently I don’t see how it does anything. It’s ok, these kids don’t hang out with the drop-out pot-heads enough to know how to fashion a bong out of an Orchy bottle. Even if you tipped it upside down during operation it would proceed to blow out all the water until it was clear and then the gas would flow straight through.
Here’s how they are usually set up to filter water:
So water comes in – is pushed or pulled through the filter – and then flows out. If you don’t have the filter there – the water just flows straight out.. If you tried blowing air through – it’d just flow straight to the exit.
So you could take that out of the system – a sign of many “perpetual motion” and “free energy” machines where they stick a big coil, magnet or a mystery big resistor or something in there.
The gas bottle
There’s some things wrong with the gas bottle too.
No clamp on the “input” – which I’m not sure what that is and how it works. Looks like a repair job, but not sure what that other bit is – looks like a plug or something on the side of it. The corrosion might be because they welded the wrong metal on there? But generally you don’t want too many valves/openings in your tank as it is a point of failure – certainly not a big drain sized opening or whatever that is.
Another water filter
Then there’s the next bit – don’t have any idea why you would have filters on the stuff going out to the atmosphere (I presume that’s what that is).
Huh? Why would you care about filtering whatever comes out that bit – either they’ve hooked up their sham rig incorrectly (e.g. this stuff with the filters should be hooked to the electrolyte cell or to the gas tank or somewhere that makes sense. Double filtering something that is going nowhere – why? Again, those could be removed for the same impact.
And finally – 6 hours of running a generator on a litre of petrol is probably pushing the friendship a bit – 6 hours of running a generator on 95% water content – unless it’s uranium or fairy dust disolved in it is probably a stretch.
While I’d love to believe the story – I just don’t buy it. There’s either something very wrong with their setup or it’s just pointlessly complex for no apparent reason.
I’m labelling this a quack gadget – in line with the perpetual energy machines, magnet only motors.. Urine powered generators are in good company.
But happy to be proved wrong and we can finally harness the grubs who piss in the street and the urinal at the pub could run the lights.
Anyone else got any thoughts?
Edit: article talking about potential for using urine talks about needing electricity to separate the hydrogen. I don’t buy that this will be capable of producing the volume and the pressures required. And another talking about batteries – but again, that was just a chemical reaction like any battery. And another talking again about electrolysis of it being a bit easier than water – but that all needs power.