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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.
zinc oxide just materializes out of thin air?
Am I the only one who gets annoyed when scientific articles use archaic scales like Fahrenheit?
It says they will use simulated sunlight matching 10,000 suns. So where would they get that strong of sunlight if this actually proves to work? Will it work with 1/10,000 of that (i.e. our sun in the backyard)?
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.
If this were true, you could ignite the hydrogen and produce fresh water and power.
I can't find out what the reaction products are from this device. So water and ZnO goes in. What happens to the oxygen that was tied up with the hydrogen in the water?
Sorry, but gray text on gray background is making my eyes bleed.
Is it any easier to transport hydrogen from where the sun shines to where it's needed as fuel as compared to electricity? It seems that the energy needed for compression and leakage from storage tanks, fittings, and transmission lines would result in significant energy losses. Plus a 200 mile hydrogen pipeline from the sunny desert to a populated area seems prohibitively more expensive than a power line.
Is this hydrogen plant really any better than just creating electricity? Granted, electricity can be hard to store in large quantities, but storing hydrogen is not cheap or easy.
How much energy and other resources will be required to first mine all that zinc and then create the oxide to use in this device? What other costs of the process are being omitted here?
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.
finally. the price at my hydrogen pump is way too high!
What is the chemical result when hydrogen is burned? Water vapor.
What is the atmospheric component that is the predominant contributor to the greenhouse effect? Water vapor.
So lemme get this straight: all these disciples of the so-called hydrogen economy want us to burn hydrogen in energy-equivalent amounts as the fossil fuels we use now, thus putting more of the worst greenhouse gas of all directly into the atmosphere? Sure, some of it will change phase and precipitate back into oceans and lakes and rivers, but about the percentage that doesn't?
If they don't compare it to PV solar, I guess like "call for price" you already know the answer.
My question too. I've been off-grid on PV solar since 1980 or so, even charge my Volt with it. 3k degrees won't be reached easily or often with the tech I know, even with trackers and concentrators. So not only "how much energy does it make vs the same sq feet of PV panels" is in question, but how much per average day per sq foot when it's partly cloudy and so forth. Gheesh and then, electricity is hard enough to store - but hydrogen? Natures way of storing hydrogen is, unfortunately, as a hydrocarbon. I guess that's why my car is electric.
Why guess when you can know? Measure!
I have tried searching Web of Knowledge and Academic Search Premier (EBSCO), and I can't find any articles written by Koepf relating to hydrogen, solar, or zinc. I can also find no papers from the advisers dealing with this subject matter. It is entirely possible that they just haven't published anything on this yet, but that seems very sketchy to get press for something that has not yet been published... Hard to say. Anyone else have any luck with finding articles?
Also, zinc oxide is produced as a by product, so what we're seeing is something like...
Zn+H2O -> ZnO + H2
The real question is how to regenerate pure zinc from its oxide. If this technology can go somewhere, producing zinc from ZnO shouldn't require any external energy input (or minimal, if any). It is also entirely possible to just ignore reforming zinc oxide back into zinc, and they probably will at first. I just don't think splitting an oxide salt will be so easy only using high temperatures. Electrochemistry may help, but again, if the net energy gain of this whole process is too low, then it's unlikely to be picked up. Still pretty cool stuff though.
Fist bump, clean hydrogen from a sustainable, renewable, source. Except for the consumption of zinc oxide catalyst... Maybe not self sustaining after all?
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.
doesn't sound terribly down-scalable to me
What about heat?
When energy reactors get small and efficient enough that every American home and African village can have one, we are going to have a big problem with heat pollution.
Or, so an argument could be made.
It's not self-sustainable. It's sustained by the sun.
It is no longer uncommon to be uncommon.
I hate university magazine technology boast articles...
Is there anything that ZnO can't do?
http://www.youtube.com/watch?v=lLp4DZmPqYE
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I find it very unusual that the college's article did not mention anything about the traditional engineering measurements on such systems.
It is always energy in versus energy out and the % efficiency and then the energy cost of recycling the zinc.
This leads me to be very speculative.
Zinc is used as a catalyst to remove hydrogen from water leaving zinc oxide. The heat come from solar radiation.
Zn + H2O + heat --> ZnO + H2
The hydrogen can be used as fuel producing only water:
2*H2 + O2 --> 2*H2O
The zinc oxide is reduced to Zn using heat from solar radiation:
2*ZnO + heat --> 2*Zn + O2
The cycle repeats and the zinc is reused continuously.
Zinc will be needed initially and it will be need to be replenished on occasion, but compared to the world's consumption of zinc (12 million tonnes per year) it's probably quite small.
Remember as well that the pollution produced by the additional production of the zinc will probably be offset by reduced emissions from burning hydrogen instead of gasoline.
All in all, I think they've got a good plan to produce hydrogen in such a way that the environmental impact is minimal and should be greatly offset by reduction in other areas.
I void warranties.
Why burn it. Just use it in a greenhouse. Isn't that what greenhouse gases are for?
now we need to go OSS in diesel cars
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.
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.
The zinc gets reused, and no form of mining is "clean", not even for Uranium, not even for sand although it has less impact than most. You've been fooled into a bullshit circular argument where the only way out is making everything out of driftwood or fallen branches.
Anonymous Cowards do not have previous statements.
Sig Battery depleted. Reverting to safe mode.
Apparently you aren't the first to have this idea. These guys filled a greenhouse with CO2, which was just waste from a nearby industrial plant. As a bonus, they heated the greenhouse with the waste heat from the plant. No surprise, vegetables grow really well in there! To me, that seems like a very efficient use of our "waste" and our land!
Here is a proposal posted on the National Renewable Energy Lab's website ( http://www.nrel.gov/hydrogen/pdfs/development_solar-thermal_zno.pdf ). It discusses in further detail the process by which ZnO is decomposed into Zn metal and oxygen, using the Zn metal to react with water to form ZnO and H2 gas.
is fueling vehicles.
Hydrogen sucks for fueling vehicles. It is difficult to compress sufficiently to get a car to have a reasonable range, and brittlizes metals used for storage tanks, causing them to leak. Hydrogen will accumulate in garages and houses, with the result that houses either begin looking like the Hindenburg if they simply catch fire, or a bomb if the hydrogen mixes with the air in the right (wrong) proportions.
IOW, this article has attached to it a "So what?" If we want to use it to store solar power for overnight commercial power for sale, we STILL have to compress it, which is STILL expensive in terms of energy, but it could be done. But solar-thermal power generation with the "thermal" part stored in the heat of fusion of molten salt is much easier. Sooo... what?
I ran across this paper on nano scale production of zinc oxide by a laser ablation method. If the ZnO is being used as a catalyst, nanostructures are useful for their increased surface area.
This might be useful for those amateur chemists wanting to build their own at home.
Yang, Li, Paul W May, Lei Yin, and Tom B Scott. 2007. “Growth of self-assembled ZnO nanoleaf from aqueous solution by pulsed laser ablation.” Nanotechnology 18(21):215602. Retrieved April 5, 2012. http://www.chm.bris.ac.uk/pt/diamond/pdf/drm17-931.pdf
I've said for years that there's nothing wrong with electric vehicles that a batter that lasts twice as long at half the price wouldn't fix. That's actually a 4X improvement, approximately, but we've improved a bit over the last few years.
Long term, I think Lithium-Iron (LiFe) batteries are going to win the automotive market - a little less energy density(though they're working to fix that, of course), but they degrade so much slower that after the first year they actually hold more charge.
I don't read AC A human right
It is self sustaining as long as it's being sustained by sunlight.
I'm not a chemist, but why not deposit the Zn vapor onto a surface and sell it to produce Zn-metal batteries?
Would this provide an electricity storage source that is more dense than Hydrogen? Since the generators are distributed, then the Zn-battery plants could be built near the furnaces and the results distributed in local markets.
Something similar to the Better World battery swap stations could replace depleted batteries with fresh ones and the depleted batteries could be sent back and refined in the furnaces.
As a distribution matter, wouldn't this be somewhat less problematic than piping low-density Hydrogen around the community?
I always get the shakes before a drop.
see ozmanjusri's comment http://hardware.slashdot.org/comments.pl?sid=2766393&cid=39581439, but if you also have CH4 (biogas from cow shit?) it becomes even easier because you can start with a methane reformer.
You can burn a bit of the natural gas to get the temperature up to 800C.
Can anyone point out if there's anything wrong with:
1. 4CH4 + 2O2 + 2CO2 -> 6H2 + 6CO + 2H2O (exothermic, high temperature high pressure, autothermal reforming)
2. condense the water out? or somehow drive the water gas shift reaction so that you've got the right proportions for CO and H2
3. 6CO + 6H2 -> 3 CO + 3 CH3OH (high temperature high pressure with catalyst)
4. condense the methanol out or use it for the (extremely dirty?) Fischer-Tropsch process to make gasoline.
To be, or not to be: isn't that quite logical, Slashdot Beta?
I think this has been done before. Check out the hydrosol project: http://www.hydrosol-project.org/ They built a device to produce hydrogen using a "solar reactor" several years ago. How is this new device different?
Is this cheaper/more efficient than electrolysis?
Solar cell+2 wires+water+capture vessel = clean, cheap hydrogen anytime there's any light at all. Scales infinitely. Can use any bulk water.
There must be some reason this is better? It's certainly not cleaner...
-Styopa
I don't think this is true. Water doesn't start to decompose until roughly 2000C. So, having something that decomposes at a lower temperature as well as a material that stays put longer (ZnO stays a solid until it decomposes) is quite a bit better.
Technically it is true alcohol has only 70% of the energy of diesel or petrol per kg or per liter. But it stores easily in room temp, alcohol tanker trucks, alcohol pumping stations exist, and all of them are grandfathered out of any new hazardous materials handling laws. All new fuels will face significant hurdles in getting past the regulations. In fact, you can't transport handle petrol/diesel under present day haz mat rules economically. That and the liability case law and precedents set up a huge cost of entry barrier to anything trying to displace these fuels.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Water vapor is the most dangerous greenhouse gas. Ignorance abounds in the land of "clean energy".
This could be a very big thing, IF it works. If the test proves that the furnace produces enough hydrogen to warrant further development, and IF that works out, we could end-up not needing oil. That would not only benefit the environment, but it would also change the politics of the middle east completely. Interestingly enough, I wrote a Fantasy novel which required a renewable source of hydrogen to power a fuel cell on a non-fossil fueled boat. Back in 2002 when I did the research into this, I found a bacterial hydrogen generator project which used a genetically altered form of algae to produce hydrogen via photosynthesis. The book is more Fantasy than Sci-Fi, because the boat is sent back in time to 1813 to commit the perfect crime. To steal gold from Napoleon as an act of war committed by the Royal Navy. You can get the first half of Napoleon's Gambit free at, http://napoleonsgambit.com/
Let the Free Intelligent develop occur and miracles can happen. There ARE ways that have and will have to produce clean, safe and plentiful energy. Get the bureaucratic idiots out of the way and reduce the overbearing suppression of new technology by entrenched industry giants and we can make this a more viable planet; and just maybe the Human Species and Planet Earth will survive!
Skip Stein Free Agent Management Systems Consulting, Inc. http://www.msc-inc.net www.linkedin.com/in/skipstein
My buddy and I did this in chemistry class in 1981, using a bunsen burner. Then we made nitroglycerin. When it turned red, we rushed it outside where it blew up the flask. We have enough hydrogen to last basically forever. This could be the key to switching from petroleum.
Nothing to see here but us trolls...move along...
Well, a Volt isn't exactly #5, but good catch. I was picturing a pure electric vehicle with a small hitch and specialized power plug in the back; that way you avoid the expense of the engine - in both cost and weight, for normal trips that don't need it. And #6 would fix you right up.
So let's add one. I ordered them for what I saw as practicality/likelihood.
7. Buy a multi-fuel vehicle; plug-in hybrid of some sort if you make a lot of long trips
In your case, I'd consider utilizing mass transit - train or bus into city core; walk the rest of the way. I'd prefer a city core optimized for foot traffic - I live in the upper north, so to me this means skybridges and perhaps even slideways in the larger city centers. At an easy 3mph, a human can travel a mile in 20 minutes. If you figure that it takes 8 minutes to get to your car, start it up, get out of the parking spot and lot onto the road, then drive at 10mph average, then take another 8 minutes to park and get to the final destination, that's 21 minutes. With slideways doubling the walking speed to 6mph, that's more like 1.5 miles where going by foot is actually faster.
By the way, have you considered the cost of your commute? That living closer to your work might be better? Assuming you work 5 days a week, that's 25% more time, 500 extra hours a year dedicated to your job, plus fuel, plus car wear, etc... I believe that it's unsustainable for most people; the suburbs are eventually going to die. Note: This means attention needs to be paid in cities, building GOOD apartments and condos and such.
I don't read AC A human right
Why is it unfortunate that nature stores hydrogen as hydrocarbons?
Hydrocarbons are far superior energy storage than any battery or capacitor technology on the horizon. As a bonus, they are the very definition of stable storage (especially when compared to caps or batts).
People need to stop conflating the source of energy with the energy storage medium. Oil can be carbon neutral if it is made via reverse combustion. Link this solar reactor's water-cracking H2 production with a similar reactor cracking CO2 into CO (similar reactants involved in a solar reactor), send it through the Fischer Tropsch Process, and get carbon-neutral hydrocarbons as output. As a bonus, you can reuse all the existing petroleum distribution infrastructure.
Furthermore, if you equip a vehicle with a next-gen solid metal oxide fuel cell then you can exceed Carnot efficiency in energy extraction from the hydrocarbons.
Scuba Tanks? Really? They're not that common on boats and aren't optimized for holding hydrogen. It'd be like trying to hold sand in a wire collander intended to drain pasta.
I mentioned it working better with a massive cylinder at a factory - economy of scale. scuba tanks would actually be smaller than the ones mounted in a car.
I don't read AC A human right