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Self-Sustaining Solar Reactor Creates Clean Hydrogen

samzenpus posted more than 2 years ago | from the power-up dept.

Power 406

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."

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Darn that dirty hydrogen (5, Insightful)

retroworks (652802) | more than 2 years ago | (#39579025)

Finally, a source of clean hydrogen.

Re:Darn that dirty hydrogen (0, Flamebait)

Anonymous Coward | more than 2 years ago | (#39579073)

Can't tell if sincere, or sarcastic and uninformed...

Re:Darn that dirty hydrogen (5, Insightful)

Fluffeh (1273756) | more than 2 years ago | (#39579081)

Finally, a source of clean hydrogen.

That is true, but isn't one of the big problems with Hydrogen storing it [wikipedia.org] , not just producing it? I mean, don't get me wrong, it is excellent to see that part of this "we want to use hydrogen" problem solved, but a lot more still needs to be done.

Re:Darn that dirty hydrogen (5, Informative)

v1 (525388) | more than 2 years ago | (#39579131)

One reason storing it is such a big deal is because generating it can be expensive. Make hydrogen easier to produce and it lowers the demands on storage.

Re:Darn that dirty hydrogen (1)

Anonymous Coward | more than 2 years ago | (#39579331)

Yeah, but this solution won't help that. You're not going to drive around hauling a 3000-degree solar zinc reactor, nor attach one to your house.

So storage and transport are still an issue.

Re:Darn that dirty hydrogen (2)

nschubach (922175) | more than 2 years ago | (#39579665)

That's why you build new houses around this reactor to channel sunlight into a centralized location in the basement!

Re:Darn that dirty hydrogen (2)

cstdenis (1118589) | more than 2 years ago | (#39579675)

Could be very useful in large scale industry -- the energy required to produce CNG or Aluminum is pretty high.

Attaching a "3000-degree solar zinc reactor" to an aluminum plant isn't going to be a big deal.

Re:Darn that dirty hydrogen (5, Interesting)

Fluffeh (1273756) | more than 2 years ago | (#39579347)

Hydrogen stored under pressure has a considerably lower energy density compared to hydrocarbons that we use. Hydrogen is great when you look at the energy by weight, but if a tank is sitting in the back of a car, it doesn't matter whether it weighs an extra twenty kilos, what matters is how far a tank can make a car drive.

Like I said, don't get me wrong, I think it is a fantastic breakthrough to have - a cheap, clean and sustainable way to make Hydrogen gas, but a lot of work still needs to be done before we can all whizz around in clean cars and certainly before we have large scale power stations powered by burning Hydrogen.

Having said that, burning Hydrogen makes water, this process turns water into Hydrogen. It would make for a wonderful closed circuit...

Re:Darn that dirty hydrogen (1)

icebike (68054) | more than 2 years ago | (#39579475)

What happened to all those storage schemes that involved Metal hydrides and all sorts of other esoteric stuff. Did any of that end up being useful?
I saw one demonstration where they shot a cylinder with a rifle and all it did was hiss quietly.

Re:Darn that dirty hydrogen (0)

Anonymous Coward | more than 2 years ago | (#39579491)

use hydrogen to make electricity, use electricity to run cars?

Re:Darn that dirty hydrogen (0)

Anonymous Coward | more than 2 years ago | (#39579587)

use hydrogen to make electricity, use electricity to run cars?

Because the weight of electricity storage is a total none issue....

Re:Darn that dirty hydrogen (1, Insightful)

FatdogHaiku (978357) | more than 2 years ago | (#39579555)

It would make for a wonderful closed circuit...

For a closed circuit wouldn't we also end up with a pile of zinc oxide?

Re:Darn that dirty hydrogen (5, Informative)

icebike (68054) | more than 2 years ago | (#39579685)

You start with zink oxide. Apparently (not a chemist here) you de-ogygenate it via heat making zink vapor (releasing O2, which is vented) and that zink vapor grabs oxygen from the water, leaving you with your H2 product, and a clean supply of Zink Oxide again.

The byproduct is Oxygen.

Re:Darn that dirty hydrogen (0)

Anonymous Coward | more than 2 years ago | (#39579581)

Given a solar concentrator to produce heat, you could always combine that hydrogen with CO2 from the air using the Sabatier process to produce methane. There's already an industry in place to store, ship and use CNG.

not any more, read about formic acid (5, Interesting)

Anonymous Coward | more than 2 years ago | (#39579647)

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.

Re:Darn that dirty hydrogen (4, Interesting)

DigiShaman (671371) | more than 2 years ago | (#39579165)

But is mining for zinc just as clean? I know you have to start somewhere. Just thought I'd throw that out there for discussion sake.

Re:Darn that dirty hydrogen (4, Insightful)

mingot (665080) | more than 2 years ago | (#39579219)

When we (the US) get rid of the penny there will be a HUGE supply of zinc out there.

Re:Darn that dirty hydrogen (0)

Anonymous Coward | more than 2 years ago | (#39579419)

Then a penny will actually be worth something. A win-win situation.

Re:Darn that dirty hydrogen (1)

Trogre (513942) | more than 2 years ago | (#39579511)

Agreed. Any denomination less than 5c is just dead weight now. I would say 10c should be the smallest were it not for the ubiquitous quarter.

Re:Darn that dirty hydrogen (1)

amiga3D (567632) | more than 2 years ago | (#39579621)

How about we just adjust the currency. Let's shift it one decimal point and everything that costs a dollar is now 10 cents and if you make 3000 dollars a month it's now 300 dollars. New currency can be issued and all the old money face value is now down one decimal place. Then a coke will be 6 cents at work instead of 60 and the penny is relevant again. No more trying to feed worn bills into the vending machine.

Re:Darn that dirty hydrogen (4, Informative)

reverseengineer (580922) | more than 2 years ago | (#39579289)

This process looks like UT actually starts with zinc oxide which gets photolyzed to produce zinc vapor, which grabs oxygen from the water to get back to zinc oxide. This process would of course not be infinitely sustainable, and eventually the zinc oxide and ceramic surface would need to be replaced, but it has the potential for minimal use of resources.

Re:Darn that dirty hydrogen (1)

icebike (68054) | more than 2 years ago | (#39579567)

So help me out here, photolyzed zink oxide is pure zink vapor, and the oxygen goes someplace, (out the stack?) and then the zink gloms onto oxygen from the water. So, wouldn't that tend to yield fairly pure zink oxide after it cools?

Re:Darn that dirty hydrogen (4, Interesting)

icebike (68054) | more than 2 years ago | (#39579339)

Clean in this context probably refers to not requiring fossil fuels.

Apparently the Zink Oxide is recoverable as well:

As well as a lack of emissions, the other good news is that the zinc oxide can apparently be reused, meaning the solar reactor is theoretically self sustaining as it only relies on materials and energy that are renewable.

although it isn't spelled out how that is performed, or if any processing is required, and if so, at what cost.

To heck with scaling this up. Lets scale it down so I can have one in my back yard, or at every corner gas station. A small reactors working any time there is sunlight and water scaled just large enough to keep your car topped off makes a lot more sense than trucking hydrogen around. Especially if the zink oxide recovery can be built in.

Then maybe hydrogen cars can become a realistic option rather than the proof of concept models and conversion kits for fleet vehicles.

Re:Darn that dirty hydrogen (4, Insightful)

CrimsonAvenger (580665) | more than 2 years ago | (#39579471)

To heck with scaling this up. Lets scale it down so I can have one in my back yard, or at every corner gas station. A small reactors working any time there is sunlight and water scaled just large enough to keep your car topped off makes a lot more sense than trucking hydrogen around.

It operates at ~1700C. You're not going to get sustained temps like that without large mirrors and large reactor vessels. So it's not going to scale down terribly well.

Re:Darn that dirty hydrogen (4, Insightful)

icebike (68054) | more than 2 years ago | (#39579637)

Well, scaled really small, it just works slower to fill your H2 tanks.
Photo-voltaic panels ---> Electricity--> heat small continuous flow reactor chamber (maybe no bigger than your thumb). Maybe the whole package sits beside your house in a package the size of an air conditioning compressor, while the panels are on the roof. We got a boat load of roofs in this country.

Re:Darn that dirty hydrogen (1)

StateOfTheUnion (762194) | more than 2 years ago | (#39579389)

Isn't hydrogen made from water always 'clean'? I'm not sure what the big deal is here considering that we can produce 'clean' hydrogen from electrolysis of water today...without all this zinc business.... Seems overly complicated to me...

Sustainable? Not really. (1)

noh8rz3 (2593935) | more than 2 years ago | (#39579583)

Fist bump, clean hydrogen from a sustainable, renewable, source. Except for the consumption of zinc oxide catalyst... Maybe not self sustaining after all?

First! (-1)

Anonymous Coward | more than 2 years ago | (#39579051)

First!

Zinc! COME BACK ZINC! (3, Funny)

squidflakes (905524) | more than 2 years ago | (#39579055)

Great, just one more think to go wrong when pimply faced teenagers wish to live in a world without zinc.

How down-scalable is it? (5, Interesting)

sirlark (1676276) | more than 2 years ago | (#39579065)

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.

Re:How down-scalable is it? (4, Interesting)

MachDelta (704883) | more than 2 years ago | (#39579187)

It seems to me that as an energy storage medium (and that's what it is, it's not a fuel "source") Hydrogen would lose out to a plain old chemical battery when all it needs to do is sit in your basement. One of the primary pitfalls of a battery is weight and size, but that won't much matter if you just dig a deeper hole in the ground and never move it.
Anyways, going Solar -> Hydrogen -> Electrical sounds a lot more complected (not to mention inefficient) than just Solar -> Electrical.

Re:How down-scalable is it? (0)

Anonymous Coward | more than 2 years ago | (#39579369)

Solar -> Electrical may be more efficient
but this would deal with the problem of nightime

Re:How down-scalable is it? (0)

Anonymous Coward | more than 2 years ago | (#39579393)

Well, you could store the hydrogen until the sun sets...

Re:How down-scalable is it? (1)

LordLucless (582312) | more than 2 years ago | (#39579505)

Google "battery"

Re:How down-scalable is it? (0)

Pence128 (1389345) | more than 2 years ago | (#39579615)

If you bothered to read the headline, you would notice that this device uses sunlight to generate hydrogen, so yes, this is a fuel "source."

Re:How down-scalable is it? (1)

roc97007 (608802) | more than 2 years ago | (#39579633)

The advantage I see is that hydrogen will fuel existing internal combustion engines. Moreover, a pitfall of batteries is the environmental cost of making them and of disposing of them -- even modern batteries do not last forever. Whereas, hydrogen will always combine with oxygen to produce water vapor, a process that doesn't change or get less potent over time.

There may come a time in the future when people will look back and wonder why we put up with those complicated, short-lived, environmentally unhealthy (relatively) chemical batteries when we could just use solar to create hydrogen and then burn hydrogen to produce motive power, (point emission being: getting the water vapor back that you used in the original reaction to create the hydrogen) or use hydrogen in fuel cells for electricity.

Re:How down-scalable is it? (2)

oic0 (1864384) | more than 2 years ago | (#39579221)

I was going to say no way... then I remembered the videos on youtube of concrete, steel, etc... being melted with a window sized fresnel lens. So... maybe.

Re:How down-scalable is it? (0)

Anonymous Coward | more than 2 years ago | (#39579551)

No.

If we could cost effectively harvest enough heat from the sun to melt zinc at 3k degrees we could already deploy very cost effective solar heating systems to keep buildings warm without requiring oil or gas. We could also direct drive air conditioning units via that turbine basically making the heat differential into cooling.

This is an interesting technology but not for distributed production of electricity. It may have more promise for supporting a hydrogen based economy though.

Re:How down-scalable is it? (1)

Pence128 (1389345) | more than 2 years ago | (#39579605)

The transmission losses are trivial compared to the gains brought by economies of scale. Also, this is for generating hydrogen. Converting it to electricity at the same place or even in a non moving generator completely defeats the purpose.

concentrated light equal to 10,000 suns (1)

linatux (63153) | more than 2 years ago | (#39579657)

doesn't sound terribly down-scalable to me

so... (1)

Anonymous Coward | more than 2 years ago | (#39579075)

zinc oxide just materializes out of thin air?

Re:so... (1, Informative)

black3d (1648913) | more than 2 years ago | (#39579089)

That's what I was thinking.. What's the carbon output of obtaining, refinement and purification of the Zinc Oxide?

Re:so... (5, Informative)

pushing-robot (1037830) | more than 2 years ago | (#39579209)

As well as a lack of emissions, the other good news is that the zinc oxide can apparently be reused, meaning the solar reactor is theoretically self sustaining as it only relies on materials and energy that are renewable.

TFAs: Read one today!

Re:so... (1)

CrimsonAvenger (580665) | more than 2 years ago | (#39579563)

Didn't actually answer his question - you've got to produce the ZiO2 once, and the recovery is never going to be 100%, so there'll be a need for steady (hopefully low-level) replacement.

So, anyone know how dirty zinc mining and refinement are?

Re:so... (1)

Pence128 (1389345) | more than 2 years ago | (#39579493)

The zinc vapour reacts with water producing zinc oxide and hydrogen gas.

Re:so... (1)

Pf0tzenpfritz (1402005) | more than 2 years ago | (#39579653)

More or less. Thin air contains ~2 micrograms of zinc per cubic metre.

40 rods to the hogshead (1, Insightful)

RenHoek (101570) | more than 2 years ago | (#39579085)

Am I the only one who gets annoyed when scientific articles use archaic scales like Fahrenheit?

Re:40 rods to the hogshead (0)

Anonymous Coward | more than 2 years ago | (#39579293)

Not when they're trying to relay information to laymen using current conventions.

No matter how archaic it is, a lot more people will understand the Fahrenheit reading, as opposed to Kelvin.

Re:40 rods to the hogshead (2)

ThePeices (635180) | more than 2 years ago | (#39579441)

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.

Re:40 rods to the hogshead (0)

Anonymous Coward | more than 2 years ago | (#39579461)

Celsius is probably what he was refering to.

Fahrenheit is understandable though, it's not like the university of delaware will have much contact with the rest of the world.

Re:40 rods to the hogshead (-1, Troll)

RenHoek (101570) | more than 2 years ago | (#39579547)

Is it not our task to educate? If people get shielded from concepts like celsius/kelvin, will they ever learn? Also, this is Slashdot.. True, an American site, but read globally. I'm sure 99% of the audience knows about all three scales, but for science stuff, kelvin or celsius just makes more sense. Like how cocaine goes by the kilo. :)

Re:40 rods to the hogshead (4, Insightful)

Anonymous Coward | more than 2 years ago | (#39579403)

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.

Re:40 rods to the hogshead (0)

Anonymous Coward | more than 2 years ago | (#39579473)

Only Americans have any idea what a fahernheit is. The rest of the world says its an archaic scale so how about Americans get with the program and move to at least the 20th century?

Re:40 rods to the hogshead (0)

Anonymous Coward | more than 2 years ago | (#39579523)

1. Fahrenheit isn't an archaic scale. It's in current usage by many laypeople and engineers...

Who live in the red zone [guzer.com] .

Re:40 rods to the hogshead (1, Flamebait)

SplashMyBandit (1543257) | more than 2 years ago | (#39579539)

The SI unit for temperature is Kelvin. The Celsius and Kelvin scales are related, which means Celsius makes rational sense. The Fahrenheit is indeed archaic, its just that the general population of the US is too stubborn to change (the US government tried to change; and the US military made the transition since the units are more rational). So your defense of Fahrenheit scale is pretty dumb (or trollish?) - no wonder you wanted to post as an Anonymous Coward.

Re:40 rods to the hogshead (4, Insightful)

RenHoek (101570) | more than 2 years ago | (#39579595)

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.

Re:40 rods to the hogshead (0)

Anonymous Coward | more than 2 years ago | (#39579557)

You should be.

I find it hilarious how otherwise bright engineering students feign complete stupidity when it comes to working with customary units.
Grow a pair, son.

Re:40 rods to the hogshead (0)

Anonymous Coward | more than 2 years ago | (#39579629)

Douche

Re:40 rods to the hogshead (1)

roc97007 (608802) | more than 2 years ago | (#39579641)

Apparently.

10,000 suns (1)

Anonymous Coward | more than 2 years ago | (#39579109)

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)?

10000 mirrors (2)

Chirs (87576) | more than 2 years ago | (#39579321)

There are already solar towers using massive arrays of mirrors all aimed at the same point. This could presumably use something similar.

Looks interesting... (4, Funny)

pushing-robot (1037830) | more than 2 years ago | (#39579117)

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.

Global Warming! (5, Funny)

sehlat (180760) | more than 2 years ago | (#39579137)

But if you burn hydrogen, it creates dihydrogen monoxide, a known greenhouse gas!

This is terrible!

Re:Global Warming! (3, Insightful)

ThePeices (635180) | more than 2 years ago | (#39579459)

water ( aka dihydrogen monoxide ) is far less of a concern with respect to the greenhouse effect than CO2 is.

Its far better on the environment to emit water vapour instead of CO2.

Re:Global Warming! (0)

Anonymous Coward | more than 2 years ago | (#39579579)

Hey, I trust everything I hear on the internet. You should read this: http://www.dhmo.org/

Re:Global Warming! (0)

Anonymous Coward | more than 2 years ago | (#39579545)

if you burn hydrogen, you don't get water. in fact, if this takes off, we would be using water as out power source. I know this is not an issue now, but I dont like where it could lead.

But is it really emissions-free? (4, Interesting)

jiteo (964572) | more than 2 years ago | (#39579193)

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.

Re:But is it really emissions-free? (1)

starmonkey (2486412) | more than 2 years ago | (#39579225)

One has to think in terms of the energy cycle. If the zinc takes less energy to mine than the energy obtainable from the hydrogen the contraption produces, then you could use hydrogen-powered machinery to mine it. Of course, it's not really sustainable if you have to mine zinc in order to get the hydrogen.

Re:But is it really emissions-free? (0)

Anonymous Coward | more than 2 years ago | (#39579323)

From the Article, (sorry, I couldn't resist) the system outputs two things - hydrogen and zinc oxide. The zinc oxide can be re-used.

Re:But is it really emissions-free? (2)

AmonRa1979 (797618) | more than 2 years ago | (#39579457)

The zinc oxide is just used in an intermediate step. It is not permanently depleted in the overall reaction. You start with zinc oxide and water. You end with zinc oxide, oxygen, and hydrogen.

You take zinc oxide, use sunlight to produce zinc vapor and oxygen. Somehow the zinc vapor and oxygen are separated so that they don't form zinc oxide again (the oxygen is no longer needed in the device and is discarded as far as the generator is concerned. The zinc is then reacted with water to produce zinc oxide and hydrogen. The real question is how does the device separate the zinc vapor and the oxygen gas after the zinc oxide is decomposed by the sunlight? You couldn't just condense the Zn as it would most likely react with the oxygen gas surrounding it.

2ZnO+Sunlight -> 2Zn(vapor) + O2
Zn(vapor)+H2O -> H2 + ZnO

Re:But is it really emissions-free? (4, Informative)

DRJlaw (946416) | more than 2 years ago | (#39579673)

The zinc is then reacted with water to produce zinc oxide and hydrogen.

Zn(vapor)+H2O -> H2 + ZnO

Nope. Zn(OH)2. You have to do something else to convert the hydroxide into an oxide.

I agree that you can't simply condense the Zn vapor into a liquid or solid. In normal thermal smelting the metal is chemically reduced to draw off the oxygen using a reducing agent such as carbon monoxide. At very high temperatures, you can force a metal oxide to form a plasma of dissociated ions, but as you indicated something has to draw off or separate the oxygen, and something also has to donate electrons to the zinc ion plasma. Might be a set of high temperature electrodes?

Re:But is it really emissions-free? (0)

Anonymous Coward | more than 2 years ago | (#39579607)

the article said the zinc oxide + heat --> zinc (gas) + oxygen, then zinc (gas) + water (gas) --> zinc oxide + hydrogen
So, the zinc is potentially reused minus the one somehow got loss, stuck to the wall, pipe, washed out with the water vapour, and etc.

Re:But is it really emissions-free? (1)

gbjbaanb (229885) | more than 2 years ago | (#39579435)

plenty of zinc in the world....aren't US pennies made of the stuff?

Anyway, from TFA:

As well as a lack of emissions, the other good news is that the zinc oxide can apparently be reused, meaning the solar reactor is theoretically self sustaining as it only relies on materials and energy that are renewable.

Re:But is it really emissions-free? (1)

TofuDog (735357) | more than 2 years ago | (#39579487)

Easy -you merely boil off the the other sunscreen components, distilling pure zinc oxide!

Re:But is it really emissions-free? (4, Informative)

DRJlaw (946416) | more than 2 years ago | (#39579513)

How do you produce the zinc oxide powder?

You burn zinc metal. Really. The zinc oxide and tower are not the interesting part. That is simply an alternative method of smelting a source of zinc to obtain zinc metal.

The deeper linked articles say "the hoppers will feed zinc oxide powder (a benign substance resembling baking soda) onto the ceramic layer, causing a reaction that decomposes the powder into pure zinc vapor. In a subsequent step, the zinc will be reacted with water to produce solar hydrogen."

Ok.

Zn(s) + 2H+ -> Zn2+(aq) + H2(g)

but

Zn2+ + 2OH- -> Zn(OH)2(s)

So the water that's left over will contain a zinc hydroxide particulate (or sludge).

The zinc hydroxide is an emission. Might be better than a gaseous emission, but it's still a waste product. If this system is truely closed with respect to zinc, then the zinc hydroxide has to be converted into zinc oxide or somehow directly smelted back into zinc vapor. That's the missing element from the article in my opinion.

Other questions: how fast is the aquoeous reaction (toss zinc in a glass of water -- it's slow at standard temperature and pressure); what is the equilibrium pressue of H2 above the liquid (if it's a low partial pressure, then you need to both maintain a vacuum over the liquid and compress the drawn-off gas); what is the net energy output of H2 versus the input of heat (assuming that you close the system with respect to zinc by drying and converting the sludge back to zinc metal).

Next step - produce "free" fresh water (1)

trelony (825975) | more than 2 years ago | (#39579201)

If this were true, you could ignite the hydrogen and produce fresh water and power.

What happens to the oxygen? (1)

cvtan (752695) | more than 2 years ago | (#39579203)

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?

Re:What happens to the oxygen? (1)

Ginger_Chris (1068390) | more than 2 years ago | (#39579287)

Seems to be the thermal decomposition on ZnO
Zinc Oxide --> Zinc + Oxygen

Followed by the reduction of water:
Zinc + Water --> Zinc Oxide + Hydrogen

If the Zinc Oxide is reusable that's pretty decent, but I wonder how it compares energy wise to other methods of water separation.

is this useful? (1)

hawguy (1600213) | more than 2 years ago | (#39579205)

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.

And what about that ZnO? (1, Insightful)

macraig (621737) | more than 2 years ago | (#39579217)

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?

Re:And what about that ZnO? (4, Funny)

alienzed (732782) | more than 2 years ago | (#39579429)

It'll cost pennies!

Re:And what about that ZnO? (4, Funny)

macraig (621737) | more than 2 years ago | (#39579527)

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.

production does not equal efficient production (4, Insightful)

ThorGod (456163) | more than 2 years ago | (#39579237)

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.

In other news... (0)

Anonymous Coward | more than 2 years ago | (#39579273)

...Zinc prices skyrocket as the entire world's supply of Zinc is ground into fine powder.

Zinc reusable, better than solar? (0)

Anonymous Coward | more than 2 years ago | (#39579275)

The article 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."

However, perhaps this is the obvious to ask, but is this project more or less efficient than some of the next-generation solar technologies? Can you give this technology an 'efficiency' value?

Re:Zinc reusable, better than solar? (1)

DCFusor (1763438) | more than 2 years ago | (#39579455)

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.

This is a threat to public safety (3, Funny)

l0ungeb0y (442022) | more than 2 years ago | (#39579309)

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.

Hydrogen (1)

chrisj_0 (825246) | more than 2 years ago | (#39579359)

finally. the price at my hydrogen pump is way too high!

Byproduct of hydrogen combustion (1, Troll)

macraig (621737) | more than 2 years ago | (#39579383)

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?

Re:Byproduct of hydrogen combustion (0)

Anonymous Coward | more than 2 years ago | (#39579449)

It all does, that is the point of the water cycle. The only way to store more water in the atmosphere is if the global temperature were higher.

Re:Byproduct of hydrogen combustion (2)

macraig (621737) | more than 2 years ago | (#39579565)

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?

Re:Byproduct of hydrogen combustion (2)

macraig (621737) | more than 2 years ago | (#39579593)

Ummm... no, I didn't get that right: "later" <--- "lather"

Re:Byproduct of hydrogen combustion (0)

Anonymous Coward | more than 2 years ago | (#39579521)

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?

Indeed. And since YOU emit water vapor every time you breathe out, please stop doing so immediately, troll.

Re:Byproduct of hydrogen combustion (1)

macraig (621737) | more than 2 years ago | (#39579659)

I already exist. I am not an additive process, I'm already here, unlike this proposed alternative to fossil fuels that would introduce water vapor directly into the atmosphere to a degree that doesn't already exist. Not only that, it will do so into an already heating atmosphere that will thus retain more of it, further compounding the greenhouse effect, further warming the atmosphere, and further retaining more water vapor.

Who's the troll?

Re:Byproduct of hydrogen combustion (0)

Anonymous Coward | more than 2 years ago | (#39579535)

Congratulations for showing that you haven't even taken a cursory glance at the water cycle. Did you skip the 7th grade?

Re:Byproduct of hydrogen combustion (1)

preaction (1526109) | more than 2 years ago | (#39579543)

How can it not return to the water cycle? If you have too much water vapor in a given section of atmosphere, it precipitates. Isn't that what clouds and rain are? Where does the water for this hydrogen come from? Space? Did everyone forget high school science class in this thread?

But I looked it up to be sure: http://en.wikipedia.org/wiki/Greenhouse_gas#Role_of_water_vapor [wikipedia.org]

Curious... No academic papers... (1)

some1001 (2489796) | more than 2 years ago | (#39579561)

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.

Re:Curious... No academic papers... (1)

some1001 (2489796) | more than 2 years ago | (#39579599)

Haha, of course, I forgot that they're already supposedly using Zinc oxide as the original reactant. My foolish mistake. Still, I wish I could find the academic paper to get a better idea than some news report.

Why make hydrogen as opposed to a steam turbine? (0)

Anonymous Coward | more than 2 years ago | (#39579671)

In the process described, they use sunlight to raise the temperature inside the container to 3,000 degrees Fahrenheit. Then they add zinc, generate zinc oxide, and use that to make hydrogen. With temperatures that high, why not just generate steam and power a turbine to produce electricity?

If the zinc actually adds to the efficiency of the processes (maybe it takes less energy to mine zinc than it will produce in the reaction), why not just use a normal reactor type to heat up the container instead of sunlight? If not, why not make electricity out of the sunlight heated water?

No undesirable emissions? (1)

dtmancom (925636) | more than 2 years ago | (#39579693)

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.
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