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.
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.
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.
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...
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.
For this reason, countries like Ecuador, Guatemala, etc. Have cell phone rates higher than developed countries like Australia and the US.
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.
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 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.
If you can do it efficiently enough, in theory electrolyzing urea then burning it to water (and nitrogen) is a net gain in 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.
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.
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.
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.
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.
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.
We are talking about urine here- 95% water.
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.
"Hour" is not a unit of energy.
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..
The most efficient hydrogen storage we know is... fossil fuels.
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).
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.
How does this part work
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?
Use the energy from the solar panel directly, why convert it to hydrogen and back to electricity?
To save on batteries you can drop the end of a low voltage DC transformer in the water.
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?
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