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Self-Sustaining Solar Reactor Creates Clean Hydrogen
An anonymous reader writes "A mechanical engineer working out of the University of Delaware has come up with a way to produce hydrogen without any undesirable emissions such as carbon dioxide. The solar reactor is capable of using sunlight to increase the heat inside its cylindrical structure above 3,000 degrees Fahrenheit. Zinc oxide powder is then gravity fed through 15 hoppers into the ceramic interior where it converts to a zinc vapor. At that point the vapor is reacted with water separately, which in turn produces hydrogen. If the prototype gets through 6 weeks of testing at the Swiss Federal Institute of Technology located in Zurich, we could see it scaled up to industrial size, producing emission-free hydrogen."
Finally, a source of clean hydrogen.
Gently reply
Great, just one more think to go wrong when pimply faced teenagers wish to live in a world without zinc.
Could it effectively be mass produced so that it could become a household item, every house having it's own hydrogen generator and turbine which can contribute to the grid? I've always thought that decentralising power production would make it greener, if only because there's less loss to long distance transmission. Either way, I'm holding thumbs for the six week trial.
But it's pointless to speculate about its utility without knowing how much hydrogen a given unit can produce, how much that unit costs, and how much maintenance it will need.
And the four giant robot arms the operator wears don't fill me with confidence.
How can I believe you when you tell me what I don't want to hear?
But if you burn hydrogen, it creates dihydrogen monoxide, a known greenhouse gas!
This is terrible!
How do you produce the zinc oxide powder? How do you produce the cylindrical structure? Not trolling, genuinly asking. If someone with more metallurgical knowledge than me tells me zinc oxide is common and easy to mine, I'll believe it. But it's a question we must ask.
TFAs: Read one today!
How can I believe you when you tell me what I don't want to hear?
I'm not an engineer, so get out your salt-lick before reading...but, they've developed a "proof of concept" device. I don't know if it's even appropriate to discuss "practical" uses of this device, yet. It's possibly a very expensive way to produce hydrogen and may not be meant to see much light of day outside academic circles.
One interesting feature of the reactor is that, in theory, the zinc oxide byproduct created during the reaction will be re-usable, making the project self-sustaining.
“This is probably the most complex device built by a graduate student in the history of our department,” added Prasad. “If he is successful, one day, we can imagine a huge array of mirrors out in the desert concentrating sunlight up into a large central tower containing a larger version of Erik’s reactor and making hydrogen on an industrial scale.”
So there's "hope", but is currently experimental:
We [they] will measure the temperature and the production of oxygen inside the reactor in real time, which will tell us how much solar fuel or zinc we are actually producing,” Koepf explained.
All of the above from TFA.
PS: I don't reply to ACs.
We here at the Clean Alternative Fuels Committee see this as just too dangerous to allow and plead to the US Government to outlaw this potentially dangerous technology. We simply can not trust the public with the ability to produce Hydrogen which could lead to the creation of Mini-H bombs. We propose the advancement of existing Hybrid technology as the clean energy alternative for a successful future and is wholeheartedly endorsed by our Charter Members: Chevron, Exxon-Mobile and Shell.
There are already solar towers using massive arrays of mirrors all aimed at the same point. This could presumably use something similar.
1. Fahrenheit isn't an archaic scale. It's in current usage by many laypeople and engineers.
2. Neither of the links in the submission go to a scientific article. One goes to a press release on the UD website, and the other goes to a blog that summarizes the press release.
3. Complaining about customary units does not make you cool or indicate scientific literacy. However, it does make you sound like pedantic, whiny bitch.
You may now go back to looking at cat pictures and masturbating.
It'll cost pennies!
Never say never. Ah!! I did it again!
Yeah, because the Rest Of The World ( aka Not North America ) uses Kelvin instead of Celsius.
Sigh...
There are far more 'laypeople' in the world who use Celsius than there are those who use Fahrenheit.
You mean if we get rid of them like the Canadians plan to do? Won't that inflate the price of our thoughts by 500%? Egads! Intellectual property will be too expensive for everyone.
Which - duh! - happens to be exactly the direction we're already inexorably headed. So to recap: add more water vapor to an already heating atmosphere, thus retaining more of it in the atmosphere, and thus further increasing atmospheric heating. Rinse, later, repeat. Did I get that right?
Ummm... no, I didn't get that right: "later" <--- "lather"
1) While it's in use by a lot of people, _most_ people don't use it.
2) It's about a scientific article, so we're talking about science. It just makes sense to use celsius or kelvin in a science topic. If we're talking about the distance between planets, we use AU or light years. If we're talking temperature, fahrenheit is not the first choice.
it can be stored in vast quantities in the form of formic acid and then released and restored in a continual cycle. there is obviously efficiency losses but apparently its very practical as it allow storage of large amount of hydrogen at a very high density in a room temperature atmospheric pressure liquid,
that is basically as safe as vinegar.
I was thinking this clean hydrogen would be perfect in so many parts of the world where their is plenty of sunlight but the land is otherwise of low value.
ps: its the nail polish like odor that gets released when ants die, and more specifically when they get crushed. its probably something they are sensitive to, so hopefully our green cars in the future dont get covered with ants in because of the pheromone.
It's not self-sustainable. It's sustained by the sun.
It is no longer uncommon to be uncommon.
Zink Oxide is recovered. Its not consumed.
Sig Battery depleted. Reverting to safe mode.
The recovery could be pretty close to 100%; the reactor's only products are oxygen and hydrogen, both of which are gases, so capturing zinc should be simple enough.
Zinc is usually found in conjunction with other metals like copper, so we get most of it "for free". Zinc oxide is actually a lot easier to produce than pure zinc, so refinement costs should be relatively low. The most common ore of Zinc, Sphalerite, is ZnS, and converting it to ZnO just involves adding oxygen and heat:
ZnS + (3)O2 = ZnO + SO2
The sulphur dioxide can be converted to sulphuric acid (H2SO4).
No carbon involved.
Besides, we already use >10 million tons of the stuff per year, and have at least a couple centuries more deposits to mine (to say nothing of recycling), so using a bit for this solar plant wouldn't even be noticed.
How can I believe you when you tell me what I don't want to hear?
If it's solar then the atmospheric heating would have been there anyways.
When our name is on the back of your car, we're behind you all the way!
I know that you're being deliberately obtuse, but for the benefit of any people who may not see through your little charade, I'll point out the key difference between water vapor and the CO2 this technology would be replacing: The half life of CO2 in the atmosphere is nearly a century. The half life of water vapor is a couple of days.
This article from 2005 on a different ZnO-Zn process may be of interest:
Zinc: Miracle Metal?
The SolZinc process described there uses carbon in the ZnO reduction, and works at 1200C, compare with 1650C = 4000F for the prototype in this post.
Key quote:
Mobile fuel cell: There are already projects to run vehicles such as buses on zinc-air fuel cells. If these could be moved down to cars, the results could be quite impressive; a vehicle using 250 Wh/mile would require only 179 grams of zinc (2.74 moles) per mile. Zinc is a reasonably dense metal at 7.14 g/cc; solid zinc would yield about 40 miles to the liter, or upwards of 150 miles per gallon (powdered forms would not be quite so energy-dense). The carbon monoxide would also be surplus in this scenario.
The actual available energy (electricity) from a Zn-air fuel cell is several times as great as what can be obtained from the same chemical input of gasoline to an internal combustion engine. The metallic zinc contains about 90% as much energy as the input carbon, and it can be converted to motion with very high efficiency. It appears likely that a solar-mediated zinc reduction process using coal could power 3.5 times as many vehicle-miles as a conversion of coal to liquid fuel.
Infrastructure is the questionable issue. If we ship zinc metal out as fuel then we have to ship it back for recycling, or get the zinc oxide to another solar plant. (If we ship hydrogen we have to manage the bulk.) But we did it with coal.
about 14 million tonnes of water evaporate from the oceans every second. I don't think we're going to make that much of a difference.
404: sig not found.
A lot of fertilizer (ammonium nitrate) is made from oil or natural gas purely because that's the easiest way to get hydrogen. There are a lot of other industrial uses for hydrogen which currently mean chemical plants are close to oil refineries and natural gas pipelines.
As a fuel hydrogen gas is a pain to store and transport in comparison to butane, propane etc or a liquid fuel, but if you can make it at sane costs where you need it then you don't need to store or transport much of it.
Nopee. Zinc is recovered. you need to do another chemical process to make zinc oxide. gee, i wonder how green that process is, which gives us green hydrogen?
Go read TFA, or go directly to the University of Delaware's page from which the TFA was sourced:
http://www.udel.edu/udaily/2012/apr/solar-reactor-040312.html
It CLEARLY states:
One interesting feature of the reactor is that, in theory, the zinc oxide byproduct created during the reaction will be re-usable, making the project self-sustaining.
Zink oxide in, heated to drive off its oxygen, exposed to water where it scavenges oxygen, which frees hydrogen, and you get zink oxide back. Probably nearly pure.
Sig Battery depleted. Reverting to safe mode.
The article assumes you went to high school and know basic chemistry. The zinc vapour reacts with water to produce hydrogen gas and zinc oxide.
404: sig not found.
To be honest, Fahrenheit is probably the single worst "traditional" unit. All others you can kinda sorta get used to, because the conversions are linear and fairly straightforward - for the most part, you can assume 2 pounds in kg, 3 feet in meter, and 1.5 km for a mile, and not be too much off.
But Fahrenheit conversion is just crazy - not only the factor is a very inconvenient 9/5, but you have to add/subtract 32, and not forget when you do it before multiplying, and when you do it after. Yes, yes, if you remember the definition of the scale, it's straightforward to reconstruct - but that requires a conscious mental effort every time.
After living in US for over a year now, it's the only unit that I still can't mentally translate right away when I hear it, nor translate centigrade to it on the fly as I speak.
Unless you are being unnecessarily pedantic, the ZnO should be considered as a one-off, sunk cost and therefore this does indeed represent "carbon-free energy":
Zinc-Zinc Oxide Cycle
The reaction regenerates the ZnO at the end of the cycle (reminiscent of a catalyst); therefore, the net reaction is H2O -> H2 + 1/2 O2. So, while the reactor requires some quantity of ZnO to bootstrap itself, very little (or no) additional ZnO should be required to keep it operating. If this particular prototype reactor doesn't fully regenerate & reuse the ZnO, then that is a limitation of the particular implementation and not a limitation of the thermochemical cycle itself.
However, if you were intending to be pedantic in the sense that almost *nothing* can be built without generating some sort of carbon dioxide emission (eg. if you consider wind energy to be "non carbon-free energy" because CO2 is produced during the manufacture of wind turbines), then please accept my opprobrium for your pedantry.
Yeah. Just as well I did a fair chunk of thermodynamics during the undergraduate and honours year levels before my PhD in (astro)physics. I'm really amazed that people in the US still cling to their archaic system and rush to its defense when the rational thing to to interoperate with the *rest of the World* (and, as I pointed out, their own military who apparently is more progressive than you, lol). I fully understand the Fahrenheit units but I'm amazed people would try desire them for any other reason than they just like old traditions. Bizarre.