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Four African girls create a urine-powered generator (thenextweb.com)
134 points by jfc on Nov 7, 2012 | hide | past | web | favorite | 77 comments

Do you remember these, or do you do a search on each link? Just a-wondering!

I remember when I've seen something, and I've written tools to perform quick searches and create the text. I then confirm by hand, and copy-paste that text. It takes seconds if the search shows what I think I remember, and about a minute if I need to work harder.

More, when I do the searches I often stumble across other items by accident, and I've made several happy discoveries in that manner, so I don't think of the time as wasted. In this particular case the search for "Urine" in the title turned up some other interesting articles in addition to the earlier one for this story, one which already had discussion, which people may have missed without the cross-reference.

Is this all you do with your time on HN, post duplicate links? You're not actually helping and just cluttering the thread.

ColinWright posts great articles to HN, and thoughtful comments to threads. He is a valued contributor.

The duplicate thread posts are irritating to some people. But they are seen as very useful by many others. You claim that this single post is clutter and is not helpful. It is not clutter. It is helpful. It provides quick easy access to previous discussion.

It would be great if people could link to the canonical version of an article, rather than each tech-blog's minimal write-up; and if people could search HN before submitting a post.

But notice that ColinWright has not complained about duplication, and is merely providing useful links to previous discussion.

You've been downvoted. Partly this is because you should either ignore, or down vote, or flag, posts that you think should not be here.


>Please don't submit comments complaining that a submission is inappropriate for the site. If you think something is spam or offtopic, flag it by going to its page and clicking on the "flag" link. (Not all users will see this; there is a karma threshold.) If you flag something, please don't also comment that you did.

I have a feeling he was kidding based on looking at his profile. :)

he can't downvote yet.

Unfortunately this looks to be mostly puff-press since we are dealing with a trifecta of minority-in-startupland (black, female, third-world country)

This weird contraption obviously uses more power to make hydrogen than it takes to run it. (Unless we are breaking some laws of physics?)

I also see no mention of why using urine is better/worse than just using regular water. I am guessing because "Putting electricity in water generates hydrogen" is a less exciting title.

> I also see no mention of why using urine is better/worse than just using regular water. I am guessing because "Putting electricity in water generates hydrogen" is a less exciting title.

This is not electrolysis of water. In theory, they are decomposing urea to get their hydrogen, which uses far less energy. This is the same principle that would cause a hydrogen economy to be run off of natural gas. Sometimes a little knowledge is a dangerous thing. Or, in the words from Spinal Tap, there's often a thin line...

There isn't all that much urea in human urine - less than 3%.

I point this out in another comment, but that's a good point I hadn't taken into account. Getting hydrogen from urea is better than electrolysis, but there's not that much urea. Still, if the entire village contributed, it might be enough to charge cell phones and run LED reading lights, which would still be a huge boon.

> Still, if the entire village contributed, it might be enough to charge cell phones and run LED reading lights, which would still be a huge boon.

If you think people in undeveloped countries need to generate power from their urine to charge their cell phones, you really need to get out and see the world.

Not all villages in developing countries are dirt-poor and desperate for the slightest technology. Cheap cell phones are used quite a bit in many rural areas in Africa, for example: http://www.cnn.com/2012/09/13/world/africa/mobile-phones-cha.... For example, farmers can use them to look up weather forecasts and price information for their crops.

I think the point is that villagers from those rural areas can generate power the old-fashioned way, by burning fossil fuels.

Yep, that's exactly what I was saying.

Granted, I really do need to get out and see the world. But I had thought that 'burner' cell phones were quite ubiquitous in the developing world?

Sure they are. Anywhere in the developing world that has power to run a cell tower clearly doesn't need to be extracting power from urine.

I would assume running wires to a few cell towers considerably cheaper than running wires to many villages. Indeed, isn't that why cell phones themselves are much more common than landlines in rural Africa?

No, it's because many developing countries "skipped" a technology. They missed out on land-lines because they were undeveloped, and now they have electricity and infrastructure, they jump straight to cell phones.

For this reason, countries like Ecuador, Guatemala, etc. Have cell phone rates higher than developed countries like Australia and the US. http://en.wikipedia.org/wiki/List_of_countries_by_number_of_...

Jeesh, it's like you're missing the trees for the forest here. Skipping technologies is the pattern but there's a reason for pattern.

Developing countries don't skip technologies out of a desire for hopscotch or something. They skip wired tech because copper wires are expensive, their expense doesn't go down over time in contrast with the increasing sophistication of chips. Conventional phone lines and electrical power are both wired tech. Thus both are harder in third world conditions.

That doesn't help. If you electrolyze water with 3% urea the vast majority of your energy is used to split water, and only a small portion of it will split the urea.

But electrolyzing water, and then burning hydrogen is a net loss in energy, and the 3% urea does not give enough advantage to offset this.

Maybe if you had some way to preferably electrolyze just the urea and leave the water alone, but then you have to deal with batch process (instead of just continually adding liquid), and the lower voltage makes the reaction too slow.

The technical paper linked from the article[0] explains how this is done. The electrolysis of urea does compete with the electrolysis of water, but it happens at a lower voltage.

[0] http://www.suttonfruit.com/pics/urea_electrolysis.pdf

edit: grammer

You still have to input energy to get hydrogen from urea, so why not just use that energy directly?

The only good reason to extract hydrogen is for storage. For example, solar energy could be used to extract the hydrogen from urea, which could then be burned at night to continue to generate power.

On it's own, any technology that requires extraction of hydrogen will result in a net loss. Sometimes a HUGE net loss.

> You still have to input energy to get hydrogen from urea, so why not just use that energy directly?

If you can do it efficiently enough, in theory electrolyzing urea then burning it to water (and nitrogen) is a net gain in energy.

I believe you are mistaken in this case. The technical paper, linked from the article, will explain better then I can: http://www.suttonfruit.com/pics/urea_electrolysis.pdf

There's probably more value in the urine as fertilizer.

Is this a common practice in Africa? If it's not, then a village already meeting its fertilizer needs can have power after dark in addition.

Depends on the salt (Na) content.

Urea is easier to break down than water. (0.37V as opposed to 1.2V) I'm no chemist, but I think that making an unstable chemical into a stable(er) one gives off energy.

Also, if it wasn't a viable way to get energy than it wouldn't run at all. I don't see any wire going into a wall socket or anything, so I assume if they had it run for six hours like the article implies there has to be /something/ there.

My main issue with it is having what looks like a gasoline generator run on hydrogen. Doing the necessary tweaks raises the technical complexity of this by an order of magnitude.


Uh, are you implying that urine is mostly urea? If that were the case, then our urine wouldn't be liquid, but more like bird poop. (The white part contains uric acid.) Urea is solid at room temp and is dissolved in water in our urine. Also, it's CO(NH2)2, so there is hydrogen there you don't have to get from water.

Article mentions a charged electrolytic cell. Charged from outside power?

I did a ctrl-f for charged in the article and didn't see it. Where did it say that?

If that is what it is, though, the entire thing is pretty much fake because a charged electrolytic cell is the same thing as a charged capacitor.

What's more, they're leading small (?) quantities of hydrogen into a metal container which (presumably) hasn't been vacuum-emptied beforehand, and so will after a while contain an air+hydrogen mixture, which while technically not oxyhydrogen, can still be ignited and make the metal gas tank explode like a pipe bomb.

The first time I tried to write this comment, I was a little flip, because I'm not sure if you're trolling.

Purging the container is very easy and requires nothing more than fire (which I think Africans have), water (I am sure they have this), a vessel for boiling the water (ditto), and a moment's thought (the linked article seems to suggest this is locally available too). It does not require any vacuum pumps.

Step 1: Fill the vessel with water and start a fire Step 2: Fill the hydrogen container with water and invert (so the open side is down) Step 3: Hold the hydrogen container so that the opening is just below the surface of the water-to-be-boiled Step 4: Wait for water vapor to fill the hydrogen container.

You now have a hydrogen container filled with water vapor and trace amount of atmospheric gases (the ones dissolved in the water and the ones adsorbed to the surface of the container). Since the urea electrolysis process produces only "dryish" hydrogen gas (the borax stage is used to remove water vapor from the as-produced hydrogen), it does not matter that the hydrogen container initially contains water vapor.

At this point, the user can either cap the hydrogen container (which will produce a poor vacuum as the water condenses) or immediately start filling it with hydrogen.

If conservation of borax is important (probably not, since I suspect that it can be dried fairly easily) one could prime the system by purging the hydrogen container with as-produced hydrogen to reduce the water content to an acceptable level before connecting it to the borax stage.

The energy used in the fire is greater than the energy content of the unpressurized hydrogen in your container.

Also may be because in places like Africa there's scarcity of water and urine which is a waste could be turned into hydrogen is still valuable.

If I could downvote you I would, but since I can't I will leave a meta-comment.

Why is it important for you call out that they are in the set of three different minorities ?

The entire tone of your post isn't constructive.

I dont feel I am calling anyone out (except perhaps the website/author). I was trying to convey that this article is only getting traction /because/ of that. It is a deceptive invention that uses more power than it creates. This is contrary to the article which would have you believe if you piss in a can you could have 6 hours of generator power.

Quite literally this device is nothing more than a fraud as it is currently written.

Article title is : "These four African girls have created a pee-powered generator"

1: It is not a generator

2: You are mistaken. Its the article author who calls out front and center they are in 3 different minorities (see the title above) - I am simply responding to that.

Not all posts need to be constructive to contribute to the discussion.

The invention is about cheaper hydrogen production + wastewater treatment. The original paper http://www.suttonfruit.com/pics/urea_electrolysis.pdf

They use nickel catalyst in the process and achieve 36% cheaper hydrogen production than water electrolysis. I don't know if the results explicitly means that it could be used as a sustainable power source. The original article doesn't mention that. The main point is cheaper way of producing hydrogen fuel while denitrificating waste water.

Amen to that. Sewage gas, on the contrary is used with great success to generate energy, both in the developing world and in the developed world. This urea-electrolysis thing, on the other hand, is plain weird, to generate hydrogen you must put energy in that you won't ever recover, thermodynamics tells you that, and hydrogen isn't something that's easily stored or transported.

Basically, the article is made up. You would be hard pressed to run a generator for 6 hours on a gallon of gasoline.

We are talking about urine here- 95% water.

The article does not say how much power the generator will produce over 6Hrs time.

You could not even idle for 6 hours with that generator in the pic. (On gasoline)

I honestly don't understand all the money and hype around "world changing" startups that creates a product or service that offer some kind of amusement/entertainment or solving a "real world problem" such as the need to know what restaurants are near one person or how much one spends in potatoes.

I wish projects like this had more support, from offering sponsorship or scholarship to the people involved in the project to do more research or prototypes, to big companies offering to help on the research of that project, something like that, and hopefully leave aside the cookie-cutter world changing android app we see every week and start focusing on things that matter. I have the feel we have become a stagnant society as far as innovation and discoveries go, we focus all our energy, money and interest in entertainment rather than in discovery and humanity development.

It's a nice sentiment, but this project isn't real. They are basically using those girls for publicity.

>1 Liter of urine gives you 6 hours of electricity.

"Hour" is not a unit of energy.

Here's a link to google's cache of the original blog post on Maker Faire Africa's site:


while I applaud the initiative, someone might want to explain to them what 'Rube Goldberg Machine' means... As others have commented there's no gain here, it would be just as well to store the solar or wind power that charged the 'electrolytic cell' and keep the energy there rather than then using that captured energy to separate out the hydrogen.

edit: as some have pointed out, yes one could just run the wind generator 'directly' into this device and use the intermittently produced hydrogen as the storage mechanism..

Except that hydrogen (in gas form) is not that easy to store to begin with and likes to leak from containers.

The most efficient hydrogen storage we know is... fossil fuels.

Sounds like this system puts out less energy than it consumes.

Do any (eg gasoline) generators put out more energy than they consume?

There is no pure energy generator. All the generators are transforming one form of energy to another. The chemical energy from gasoline is transformed to heat (thermal energy) + mechanical energy + other forms of chemical energy (CO, CO2 and others). The mechanical energy is then transformed into more heat and electric energy (if we're talking about an electrical generator).

What makes gasoline a good energy "producer" is the simple way the chemical energy can be released and the percentage of usable energy (the efficiency of the generator). What makes other substances bad energy producers is the efficiency and complexity of changing the energy to usable energy (like mechanical or electrical energy).

More energy is given off from burning petroleum than it is taken from extracting it from the earth.

Sorta different situations. This contraption is extracting hydrogen from urine.

Gasoline engine just consumes/runs on gas.

Whats being said is that there is skepticism that the hydrogen extraction takes more energy than the hydrogen yield you receive.

> 1. Urine is put into an electrolytic cell, which separates out the hydrogen.

How does this part work

IIRC you stick an anode and kathode into the urine, separated by a semi-permeable membrane. This takes power of course. I'm not entirely convinced yet. Saying something gives you "6 hours of electricity" means nothing. My watch battery gives me years of electricity for example.

If you stick a pair of charged contacts in a container of water, you'll see bubbles produced at each contact. The cathode produces hydrogen.

Go get a 9 volt battery and try it right now. Just drop it in a cup of water. Presto! Hydrogen!

Use solar power as a source of electricity, and who cares about efficiency?

So what does that have to do with urine?

Use the energy from the solar panel directly, why convert it to hydrogen and back to electricity?

The idea is that their electrolysis unit is fed by the generator, which is in turn fed by the hydrogen from the electrolysis unit. To make the contraption somewhat more scientific-looking (and less suspect), they've put two water filters in the loop, presumably to 'purify' the hydrogen.

Does the article say that the generator runs the electrolysis? I don't see where it does.

A reason, though perhaps not theirs, storage. If you have excess wind/solar you could use a hydrogen generator to create enough to provide some minimal power for low production times or overnight.

The people who get the bill for the solar panels presumably.

Does this really work with a 9 volt battery? That would be a cool thing to show my kids.

Yeah, it's awesome. You can also try different electrode materials (connected to the battery with alligator clips) to make the water turn mysterious colors. Copper is the coolest in my opinion, if you salt the water it will go through multiple oxidation stages over time and change from green to yellow to black. (Oh, and if you use copper and let it react for a really long time, it will form copper tetrachloride and if you mix that with copper sulphate (blue crystals used to kill roots, get it at most any hardware store) you can come up with this crazy stuff that will eat up aluminum foil like some kind of nasty acid but does nothing to human skin.)

Yes. Make the water salty to increase the effect.

To save on batteries you can drop the end of a low voltage DC transformer in the water.

These girls banded together and built something. Whether it's a rousing success or ends up being a bad idea, there is something positive to be said for their efforts. If you consider the cultural context in which they are operating, they deserve praise for this.

Heck, we praise people who build failed webapps here in the US, in part because it's an exercise in execution. When people build new things, it's great even if it doesn't work out, because who knows what it could lead to?

Did anyone read "http://www.suttonfruit.com/pics/urea_electrolysis.pdf linked within the article. That's a paper that illustrates direct hydrogen production from urine without electricity (a chemical process)! Making the whole idea a little more plausible.

I am awestruck that there may be a day we all have urinals in our bathrooms because it helps lower our electricity bill.

Anything that uses electricity to take hydrogen out of water will use more electricity than it produces.

When you read this paper closely you will recognize that the authors have discovered a way to remove bound nitrogen from effluent. It's possibly an advance over the well-established biological reduction of nitrate, considering that instead of putting energy in in the shape of methanol you can recover a part by burning the hydrogen the process generates - possibly in the sewage gas plant that you already have on site.

My friend works for a small startup in SF called Fenix International. Their device for providing power in places like Africa is much more promising www.fenixintl.com/

You could at least explain the basics behind how the device works rather than making us type in a url. As it is, I have no interest in looking into your friend's product.

Sorry, I posted from my phone just before a meeting.

The device is called ReadySet and is a high-quality personal power generation unit with battery for storage. It can be powered by putting it beneath the rear wheel of a standard bicycle or the included 15-watt solar panel. http://www.fenixintl.com http://kck.st/LP5NjI

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