New Sunlight Reactor Produces Fuel

eldavojohn writes "A new reactor developed by CalTech shows promise for producing renewable fuel from sunlight. The reactor hinges on a metal oxide named Ceria that has very interesting properties at very high temperatures. It exhales oxygen at very high temperatures and inhales oxygen at very low temperatures. From the article, 'Specifically, the inhaled oxygen is stripped off of carbon dioxide (CO2) and/or water (H2O) gas molecules that are pumped into the reactor, producing carbon monoxide (CO) and/or hydrogen gas (H2). H2 can be used to fuel hydrogen fuel cells; CO, combined with H2, can be used to create synthetic gas, or "syngas," which is the precursor to liquid hydrocarbon fuels. Adding other catalysts to the gas mixture, meanwhile, produces methane. And once the ceria is oxygenated to full capacity, it can be heated back up again, and the cycle can begin anew.' The only other piece of the puzzle is a large sunlight concentrator to raise the temperature to the necessary 3,000 degrees Fahrenheit. The team is working on modifying and refining the reactor to require a lower temperature to achieve the two-step thermochemical cycle. Another issue is the heat loss which the team claims could be reduced to improve efficiency to 15% or higher. Since CO2 is an input, the possibility exists for coal and power plants to collect CO2 emissions to be used in this process which would effectively allow us to "use the carbon twice." Another idea listed is that a "zero CO2 emissions" is developed along these lines: 'H2O and CO2 would be converted to methane, would fuel electricity-producing power plants that generate more CO2 and H2O, to keep the process going.' The team's work was published last month in Science."

Comments

Equal parts excitement and antipathy

[jeffmeden]

Another idea listed is that a "zero CO2 emissions" is developed along these lines: 'H2O and CO2 would be converted to methane, would fuel electricity-producing power plants that generate more CO2 and H2O, to keep the process going.'

So basically, it would be a solar-powered station that could run around the clock using methane as a storage medium. I know that for as awesome as this sounds, it is equally unlikely to ever come to fruition to the extent that it is explained here.

Re:Equal parts excitement and antipathy

[clonan]

The article said it had a 15% conversion rate.

You are better off using compressed air and turn a turbine.

Re:Equal parts excitement and antipathy

[NEDHead]

Did anyone note the 15% efficiency?

  Not exactly rocking that boat, not clear that it is cheaper to implement than photocells, useless at home. Interesting, and maybe addresses a way to turn the sunlight into tankers of liquid fuel, but ....

Re:Equal parts excitement and antipathy

[el3mentary]

Or we could stick tubes up Cow's asses to harvest methane.

Re:Equal parts excitement and antipathy

[Anonymous Coward]

gasp, or wait until they build better reactors, or gasp, wait until they scale to MW size reactors, or gasp, use it in places where turbines make no sense, or gasp, use it in addition to turbines.

oh my god, he's being asphyxiated from the device's CO2 emissions! someone help!

Re:Equal parts excitement and antipathy

[jklovanc]

From the article;
'Currently, the system harnesses less than 1% of the solar energy it receives" and 'William Chueh suggests that efficiencies of 15% or higher are possible'.

So 15% has not been reached yet

Loads of Potential

[Philomage]

The summary covers a lot of it, but this is pretty fascinating (if it reaches production): something that can be added to the exhaust of a fossil fuel power generation station that reduces the carbon footprint and provides fuel to use in either that or other processes in addition to supplying oxygen for other processes. All it really takes is concentrated sunlight for an energy source.

I'd be interested to see in a few years what other uses are figured out for it.

We live in interesting times...

Re:Loads of Potential

[Daniel_Staal]

And that's what's probably the better long-term goal here: Convert atmospheric CO2 into some gasoline-like fuel, and use that as fuel in more mobile or space-constrained applications, where it generates CO2. You are back to a closed loop again, and humanity can be sustainable on our current resources. (With the external energy input of the Sun.)

Of course, you'd be limited by the amount of energy you can harvest from sunlight, but that's really a problem no matter what you do, in the longer term...

Re:Loads of Potential

[wjousts]

But your solar plant "freeing up" fossil fuels is not removing CO2, those freed up fossil fuels are still adding CO2 to the atmosphere. This system removes CO2 during production which is released again during burning, so overall, it's carbon neutral. But as Philomage has already replied, there is no reason this can't be in addition to solar plants.

The point is that cars still largely run on gas, and a carbon neutral way of producing gasoline is a better short term solution that solar power and electric cars. Also, those fossil fuels aren't just used for burning. They are also important chemical feedstock for producing a huge range of products that make modern life livable (plastics, pharmaceuticals, etc). A solar plant won't solve that problem.

Headline!

[rumblin'rabbit]

World Energy Problems Solved!
4th Time This Month

Re:CalTech?

[fahrbot-bot]

Not exactly. From TFA... The prototype reactor was designed and tested at CalTech, using electrical furnaces to generate the required 3,000 degrees. They then went to Switzerland to use the Paul Scherrer Institute's High-Flux Solar Simulator - "capable of delivering the heat of 1,500 suns" - to test with a solar heat source.

So it was *mostly* CalTech guys, using Swiss equipment for testing and further development.

Alternate idea

[dkleinsc]

I've discovered a system that allows sunlight, groundwater, airborne CO2, and a few other elements to be converted into substances which can easily be used for heating fuel, building materials, and even in some cases food. It's really amazing, and costs relatively little to set up and even less to maintain. It's also aesthetically pleasing, so you get very little complaint from the NIMBY crowd. In fact, this system is so simple that you'll often find it in the front and back yards of ordinary single-family homes, apartment buildings, and office complexes.

Not that this idea isn't potentially nifty, of course.

Re:Alternate idea

[wierd_w]

Harvesting perhaps, but using I don't see as too much of an issue as long as you pelletize it first.

Pellet stoves and pellet heaters produce very little smell or smoke, and burn the fuel much more efficiently than say-- a fireplace.

(Can also utilize grass clippings and garden waste, once pressed into pellets.)

How expensive is this thing Cerium?

[140Mandak262Jamuna]

That strange and exotic metal Cerium, is it at least cheaper than gold? How rare is this? Admittedly it sucks to have our oil stuck under their sand, but trading it for our Cerium stuck in their jungle is not a better solution either.

Re:How expensive is this thing Cerium?

[Anonymous Coward]

According to http://www.chemicool.com/elements/cerium.html

Cost, pure: $162 per 100g
Cost, bulk: $1.20 per 100g
Source: Cerium is the most abundant of the lanthanides. It is not found free in nature but is found in a number of minerals, mainly allanite, bastnasite and monazite. Commercially, cerium is prepared by electrolysis of the chloride or by reduction of the fused fluoride with calcium.

The increased cost of the pure element Ce comes from refining it via electrolysis from it's naturally occuring state in various rare minerals. The article does not seem to mention the energy costs of refining the Cerium. So, although with this element, no electrolysis is needed to separate C from O2, electolysis is needed to obtain the element itself. Nothing is free (except Linux maybe).

Re:How expensive is this thing Cerium?

[olsmeister]

Another rare earth, which China has started rationing to the rest of the world ...., as I sit here watching the Chinese president speak from the White House.

Re:How expensive is this thing Cerium?

[vlm]

That strange and exotic metal Cerium, is it at least cheaper than gold? How rare is this? Admittedly it sucks to have our oil stuck under their sand, but trading it for our Cerium stuck in their jungle is not a better solution either.

It's strange and exotic, at say, McDonalds or Pick n Save food store. On the other hand, Home Depot probably sells cans of it and its widely industrially available in bulk and used for all kinds of things.

Its extremely cheap compared to gold. Heck its pretty cheap compared to nickel, tin, and only about twice as costly as copper. Its about ten time as expensive as bulk raw aluminum per pound.

Its a relatively common semi-industrial metal used in all manner of catalysts and especially grinding processes. Cerium Oxide grinding paste sells for about $10 per pound. You can pay more retail in small cans if you'd like, or perhaps you could contract down to 50 cents per ounce if you bought a unit-train of railroad cars worth of it.

Ask your local (working, not retail) jeweler, whom probably has some quart cans of different size grits for polishing stuff.

Unlike the polishing / grinding industry, the catalyst industry would probably recycle heavily. So I'm thinking it would remain relatively cheap even if usage increased.

Re:How expensive is this thing Cerium?

[I8TheWorm]

http://en.wikipedia.org/wiki/Cerium
http://www.radiochemistry.org/periodictable/elements/58.html

India, Brazil, USA, Sweden.

It's the most abundant of rare earth metals, and is low to moderate toxicity.

Re:How expensive is this thing Cerium?

[h4rr4r]

If need be the electrolysis can be done with solar or nuclear power. The real question is how much of it does this need and how often must it be replaced.

Re:Simply Amazing ~ Free Energy

[gstoddart]

Why haven't we thought of taking advantage of this abundant, renewable and FREE resource before????

I believe we've been thinking of it for decades ... but, apparently, it's hard to actually do on a large scale and affordably. At least, that's kinda the impression I've gotten over the years.

Old News

[jklovanc]

This has already been discussed two years ago here http://hardware.slashdot.org/story/08/01/06/1620228/Scientists-Recycle-CO2-with-Sunlight-to-Make-Fuel.

Re:Why bother?

[geekoid]

You would think with someone who can manage to type out the chemical chain you would know the sun doesn't shine at night. SO you need to STORE the energy.

But no, you go on poo-pooing the idea without bothering to think in any logical or rational manner. We certainly don't have enough people like that already~

Have you considered working for Glen Beck?

Patent trick

[Iffie]

This is old stuf, but the metals originally proposed are not rare and the patent has expired. I did a piece about it here.. http://www.greencheck.nl/index.php?/archives/279-De-Rare-Earth-Mythe.html It shows the patents and the reactions proposed. Supressed technology is reintroduced as an invention. Cerium spiked up 600 perscent last august..

Re:Simply Amazing ~ Free Energy

[vlm]

I find it truly amazing that we can utilize this gigantic ball of burning energy that shows up every single day to help power things on Earth. Why haven't we thought of taking advantage of this abundant, renewable and FREE resource before????

MTBF, on an annualized basis, is almost exactly 12 hours. On a month to month basis, especially in polar areas, it approaches zero roughly once per year.

Re:Re-re-re-repost!

[SnarfQuest]

This reactor produces one of the most important components of a Hydrogen Bomb, and thus should be banned! And everybody knows that reactors are evil, and will cause the China Syndrome (whatever that is), which will kill us all. Reactors are well known to explode in a nuclear conflagration, as well as poisoning everyone within a 1000 mile radius before they do!

Of course environmentalists are going to hate this.

A more immediate likely problem

[VernonNemitz]

While a "hydrogen economy" in whatever broad implementation is a fine idea in theory, there is one extremely important detail that must be done very carefully right from the start. The leakage of hydrogen gas must be kept to an absolute minimum. Why? Simple! Just multiple any X amount of leakage you choose, per person, by a couple billion users in a scaled-up hydrogen economy. Now factor in the simple fact that all leaked hydrogen will naturally rise through the atmosphere to the ozone layer, and that ozone is naturally "hypergolic" with hydrogen --the two chemicals instantly react. If you thought the effect of chlorocarbons was bad for the ozone layer, well, "you ain't seen nothin' yet", as the saying goes, if a large hydrogen economy doesn't do everything it can to keep hydrogen gas leakage to an absolute minimum.

Re:A more immediate likely problem

[Cyberax]

Not really, ozone is constantly replenished by our friendly nearby star. And once H2 reacts with ozone it's just a harmless water vapor.

The problem with CFCs - they essentially catalyze O3 decomposition, while not being affected themselves.

Re:A more immediate likely problem

[Anonymous Coward]

Comparing hydrogen to CFCs is a bit of a stretch. First CFCs were used as a propellant that was INTENDED to be released in the atmosphere.

Second the reaction of hydrogen with ozone results in water - one H2 molecule will affect 2 O3 molecules H2 + O3 = H2O + O2.

The chemistry of CFCs is much more detrmimental, in that each Cl ion will affect thousands of O3 molecules as it converts into ClO which then reacts with another ozone molecule resulting in O2 and Cl. This frees up the Chlorine ion to continue the cycle until it eventually falls out the ozone layer or reacts with some of the other elements to form a more stable molecule.

Re:A more immediate likely problem

[choongiri]

Now factor in the simple fact that all leaked hydrogen will naturally rise through the atmosphere to the ozone layer, and that ozone is naturally "hypergolic" with hydrogen --the two chemicals instantly react

Not quite, although you clearly know enough chemistry to have confused yourself, or accepted someone else's confusion.

Molecular hydrogen is far shorter lived in the atmosphere than inert CFCs. That's why CFCs were such a problem - they hang around in the troposphere long enough to mix up into the stratosphere. Molecular hydrogen is for the most part scrubbed out by the hydroxyl radical (OH) in the troposphere (via H2 + OH --> H2O + H and bacterial decomposition by soil).

So, any effect of hydrogen leaks on stratospheric ozone has to do with increased water vapour rather than direct reaction of H2 + O3. (Stratospheric water provides the surfaces required for ozone depletion reactions to take place on - polar stratospheric clouds - that's why water is important. See http://www.esrl.noaa.gov/gmd/about/ozone.html)

That's not really relevant, though, as estimates put the effect of even substantial hydrogen leaks on ozone depletion so small as makes no difference:

http://www.arp.harvard.edu/sci/climate/journalclub/Pyle.pdf

There was an earlier study claiming it was a problem, but that's basically been debunked, both by the paper above (which assumes there will be significant losses, but finds they don't affect stratospheric ozone) and - much more recently - this paper which estimates that losses will actually be very low, comparable to hydrogen production from our existing vehicles (yes, internal combustion engines release small amounts of hydrogen).

I am an atmospheric scientist, I am not your atmospheric scientist, etc...

Re:A more immediate likely problem

[VernonNemitz]

This seems like the best reply to my prior post, so this is where I'll respond.
I was fully aware of the catalysis problem posed by chlorine in the ozone layer.
But none of the detracting replies, except perhaps the last, paid attention to the fact that in a hydrogen economy, leakage of hydrogen will be as constant a thing as production of ozone by solar ultraviolet. The only question is, which rate will be greater? If a huge worldwide hydrogen economy leaks the gas faster than ozone can be formed, then the outcome is obviously detrimental to the ozone layer.

Now, the preceding message points out the existence of large amounts of hydroxyl radicals in the atmosphere, about which I had been unaware. But all this really means is that there are two rates in favor of the ozone layer, the first being the rate of production of hydroxyl radicals. So, for the ozone layer to be seriously harmed by hydrogen leakage, the rate of leakage would have to be approximately equal to the sum of the other two rates.

Meanwhile, of course, there is the simple fact that the less hydrogen is allowed to leak, the better for business (fuel is money). But this fact is balanced by the costs associated with minimizing leakage. I once read a study (long before the internet) about a test of putting hydrogen through existing natural-gas lines, to see what the leakage rate would be. The experiment validated some theoretical work, indicating that hydrogen would/does leak out of the gas lines (mostly through pipe joints) at three times the rate as natural gas. Actual quantites I have not remembered (if they were actually specified in the article), so I don't know if such a leakage rate is low enough to be cost-acceptable for the hydrogen-production business --or if all the natual gas piping would have to be upgraded to be used for hydrogen, an obviously huge and expensive undertaking. But even if the existing piping leakage rate was still cost-acceptable for business, that quantity of constant leakage, applied to all the natural gas lines in the world, needs to be studied in terms of what it might do to the ozone layer, if we had a large worldwide hydrogen economy. With, of course, included in the study other sources of constant or equivalent-to-constant leaks (like individual auto accidents are isolated, but the worldwide rate is some-seconds-per-accident, equivalent to a constant rate).

From GHG to pollutant to GHG and pollutant

[davev2.0]

CO + 2O2 -> CO2 + O3

So, we end up with ground level ozone and CO2. Yay.

Mars

[Daniel Phillips]

Could be useful for producing fuel and possibly oxygen at the same time on Mars. While the sunlight intensity is about 43% vs earth, atmospheric diffusion is less so the solar energy arriving at the surface is about 59% of earth. The effect of much lower gas pressure is beyond my powers of deduction. One thing the article glosses over is whether the process produces free oxygen during the heating phase, which would be very useful on Mars.

Re:Oil = yesterday

[Nutria]

Oil is going nowhere fast,

Oil goes *lots* of places, really quickly, thru an incredibly large network of pipelines all over the world. And in Really Really Really Big Ships that carry it half way around the world at 20 knots.

It's that ease of transportability along with the fact that pumping continues day and night (almost) regardless of the weather which means that people will want to use Oil for a long time.

Re:Re-re-re-repost!

[Max Littlemore]

I half agree with you.

i've long thought that amoung "environmentalists", a further distinction needs to be made between the rational ones and the loonies, hippies, and people afraid of weasel-words like "chemicals" etc.

I am an environmentalist, in that I think only people who are so stupid as to be bordering on sub human could possibly think that what we do to our environment doesn't effect us. I feel, and this is a moral point, that people who disregard the ill effects of their actions on the lives of others don't really deserve their own. It's only fair.

I also can't stand idiots who do stupid things like argue against dredging Port Phillip Bay (something I didn't support) to let large ships in but then go and say we can't build a major port at Hastings (which already has deep see access and is closer to our major industries). Because the mangroves their are not found anywhere else? They are found right the way around Western Port!! Idiots!

you could almost split environmentalists down the middle along the lines of pro-nuclear and anti-nuclear and you'd get most of the reasonable ones on one side and the loons on the other.

This is where you lost me. I'm assuming you think anyone who is anti nuclear is a loon.

For my country, I am anti-nuclear and anyone who is pro nuclear for my country is a loon. Current technology only allows for fission, which is a dirty and inefficient power source. I have read estimates that for us to switch from the brown coal we currently burn to modern fission, our total CO2 output will rise over the life of the plants. And there is still the waste problem to consider, it's still not resolved, and no we don't want to bury it inland here and have to get into our ground water thank you very much.

I live in a country with the highest levels of solar radiation on the planet that also has an enormous coastline. Parts of it sit in some very reliable low altitude wind currents. We have large reserves of natural gas. Those of us who think solar thermal, wind and tidal power supplemented by natural gas are the way to go are a hell of a lot more rational, from both an environmental and economic point of view.

Re:Re-re-re-repost!

[mug funky]

i'd be interested in seeing those stats (as another Melbournite).

btw, check this out:

http://en.wikipedia.org/wiki/Traveling_wave_reactor

i'm not saying go down the pressurized water reactor path (with it's associated "waste" problems), but i think that nuclear power presents far more possibilities than those that have been investigated, like the ability to get rid of all that nuclear waste by burning it for power (including the lighter fission products).

also, being of anglo-celtic descent, i am well aware of the solar radiation problem australia has. however, i'd also like to see figures relating to the amount of power current practical solar can get us, and the carbon cost of implementing all that.

i don't mind the wind farms.

usually what i (glibly) say to nuclear kneejerk types is "why not mine it? surely it's dangerous to have all that radioactive stuff just sitting underground in a world heritage area", but of course this is said in sarcasm.

though nuke may not be the most elegant solution, it is a realistic one at least in theory. the blind fear of it by the public and legislators i think is a major obstacle in lowering carbon emissions while maintaining industry and our own decadent lifestyles (come on, we don't really need tellies that big do we?).

aside - on the port at Hastings thing, i doubt anyone would notice :) it's a grey and smelly area in an oasis of lovely coastline. i'd say it's the perfect place to build a port, so long as the monash freeway doesn't get any more clogged than it is already.