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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."
http://tech.slashdot.org/story/10/12/24/2216257/New-Solar-Reactor-Prototype-Unveiled
It's mainly produced by the Swiss Federal Institute of Technology (ETH in Zürich) and built at the PSI (a research facility near Zürich).
Ya, there are also some CalTech guys participating.
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.
its "Caltech" not "CalTech"!
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...
It won't be very big.
The balance of energy says that, even at 100% efficiency, the amount of energy generated by burning the combustible fuel, can be no larger than the amount of sunlight collected to convert the CO2 back into the combustible fuel.
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????
He who knows best knows how little he knows. - Thomas Jefferson
World Energy Problems Solved!
4th Time This Month
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.
I am officially gone from
1) Profit!
Am I eval()? - http://www.monst3r.com.br
else can produce lots of heat and runs 24/7 without depending on weather or time of year?
Bonus hint: it can also produce an ass ton of electrical energy!
Bonus Bonus hint: it doesn't produce CO2
Bonus Bonus Bonus hint: there is enough fuel for several thousand years chilling that's easy to get to
Bonus Bonus Bonus Bonus hint: you can also use the waste as fuel
Anyone? Anyone? Bueller? Bueller? Aww screw it....
Effectively what they're doing is turning sunlight into chemical energy. The process sounds complex at first glance, so can it be more efficient than other methods of capturing solar energy? From a technical POV the percentage of sunlight captured is interesting. But from a business POV the costs are interesting, and I think overall more important: real estate footprint, amortized capital costs, and operational costs. Where do these fall relative to other methods?
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.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
This does not make any sense. A simple chemical reaction of methane burning is CH4 + 2*O2 -> CO2 + 2*H2O + 890 kJ/mol energy freed during the process.. So in order to convert CO2 and water back to methane and oxygen you need to spend the same 890 kJ/mol energy. Okay, you get the energy from the sun, but why not to use the sun to generate the energy directly without doing the CO2 conversion back and forth?
The gigantic ball of "burning energy" is the sun. It doesn't show up every day---we do, as we rotate around the globe, alternating being in the shady side and the sunny side of the earth.
Also, the resource may be free, but the cost of utilizing it isn't. It's like the gold and other precious metals dissolved in the ocean water. This "free" resource is there. You could extract more gold than your most wild dreams. The cost of extracting the precious metals from the seawater, however, will be quite significant---especially compared to the value of what you extracted.
So, the only real novel thing here is utilizing solar energy to heat the backwards fuel cell. The "reactor" isn't really new.
Anyhow, If they can make it work reliably, efficiently, and cost effectively, they may be on to something.
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.
So, let me get this straight: Caltech scientists are telling us that, "Okay, we've got this awesome machine going on! See, it stores energy from the sun in a useable form, and does it by stripping the oxygen off the CO2 molecules, which it can then exhale in a way that's also useful to us. Totally game changing!"
And after we applaud them for this, their plan is to say, "Yeah, and it's called a plant, morons!"
Information theory is life. The rest is just the KL divergence.
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..
I'm getting a little tired of all this future tech stuff that sounds like it will solve all of our problems, but never seems to come to fruition. throw this one on the list with Transporters and Warp drives.
Sorry, but every time I see solar (or geothermal or wind or tidal) as described as "renewable", I get pissed off.
How exactly do you think we would "renew" the sun when it runs out of energy? Use a big laser to push photons back in?
--Joe
This has got to be the oldest news story on Slasdot at about 4.6 Billion years too late.
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.
Oil is going nowhere fast, no matter where all the replacements come from.
Build your own energy sources from scratch. http://otherpower.com/
CO + 2O2 -> CO2 + O3
So, we end up with ground level ozone and CO2. Yay.
"The only other piece of the puzzle is a large sunlight concentrator to raise the temperature to the necessary 3,000 degrees Fahrenheit."
or better yet, rather than wait for some pie in the sky orbital solar array... how about use a nuclear reactor so we can make this a viable option NOW and get the infrastructure in place. Once these devices are in common use, it would be economically prudent to convert them to solar power as soon as the tech was available. Making hydrocarbon fuels from nuclear power would be a huge step in the right direction, this all green or nothing attitude is what's killing progress in the field.
Hmm... If nobody has to work, then why would the people that work on WOW want to continue to do so?
Using a cryogenic separator, pull CO2 out of air (now considered a waste product or at best sold as dry ice) and use it as feedstock, and power the ceria reactor with solar during the day and thorium at night... Then reformulate (again, using thorium power) into common hydrocarbon motor fuels or other hydrocarbon-based product (fertilizers, plastics, etc) precursors.
Unless, of course, you build a gigantic Solar plant that can provide power for all phases of the process, but given that we have the thorium for hundreds if not thousands of years, and with reprocessing we can likely fit a year's national waste in a cube van, not implementing modern, safe, molten-salt reactors would be the most obnoxious form of NIMBYism and eco-luddism..
You know, it's people like you that keep us from the Star Trek future of tolerance, peace and plenty that Osama bin Laden is trying to lead us into.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
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.
Have you got your LWN subscription yet?
I always see so many stories about up coming technologies with almost no info on when it will be available to the masses, just some sort of working on fine tuning, or last minute issues, or have complications for funding...never, will be sold publicly in 2 years, deal has been signed with xxx to manufacture product.
Please shut your trap, you are making too much sense.....
Tsukasa: All I really want, is to be left alone...
Schemes like this sound nifty-keen.
Until you bring in those spoil-sports, the physicists and thermodynamicists.
You see there is a very basic fly in the ointment.
You see these folks have not repealed the Carnot Cycle.
Nor the law that says that energy transfer goes up as the fourth power of the temperature.
Not to mention the problems with any device without clear input or output ports.
Those pesky little details kinda dooms any scheme that requires very high temperatures and has no clear physical input-output paths.
The overall efficiency, with all burdens considered, usually turns out to be miniscule.
it's called a "tree."
portable energy density. Right now, you still can't beat oil. When oil gets too expensive, you won't be able to affordably create and distribute the means to use substitutes.
As for electrical power, there are lots of solutions, none of which will make a corporation money (solar tower turbines, ubiquitous small scale hydropower, ubiquitous wind and wave power, ubiquitous slow wave hydropower in the Mississippi, ubiquitous solar, geothermal in some spots), so you can forget those.
My suggestion? Dig in and prepare yourself for a long, unpleasant adjustment.
Please do not read this sig. Thank you.
What about sending one of these to Mars with a nuclear reactor instead of sunlight for the heat source, and using it to make rocket fuel for a return vehicle?
Or is this basically the same thing that Robert Zubrin proposed 15 years ago?
-Taylor
Worldwide Military budgets: $2100 billion. Worldwide Space Exploration budgets: $38 billion. Really, world? Really?
What in the world will the climate change doomsayers have to say when CO2...A DANGEROUS GAS is used and taken out of the atmosphere...
I guess mostly they will complain about boring news. Nothing exciting happening, like hurricanes, floods, droughts. No sharks swimming down Main Street. There will be mild summers and winters, no extreme temperatures without the atmosphere receiving that extra energy kick from CO2.
CO2 is found in the atmosphere at concentrations of a few hundred ppm. Extracting sufficient CO2 from the air to make this work economically would be non-trivial. I like the suggestion in the article to capture coal emissions and recycle them via this process to methane or syngas, but even that would involve some real engineering challenges. All that being said, I'm glad they're looking into this - it seems to have some potential as an energy source.
(slips on John C. Dvorak buzzkill hat...)
...back to you."
[...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.']
Uh, this sounds like a perpetual motion machine scam. These researchers might be deluding themselves. In the process, we'll waste (via gov't funding grants) asstons of money on pursuing an unfeasible, impractical, but tantalizing idea.
A few flashy startups will be created later, promising viable technology that's always "just ahead." You know...along the lines of hydrogen fuel cell scams. The technology will seem new to Wall St. analysts and newsies each time.
Channeling and paraphrasing the inimitable Lewis Black, "Green Jobs! Green Jobs! What can I say?!
USNG: 14TPU4605
... and capture CO2 with chemical scrubbers.
I'm not saying that we shouldn't pursue this technology, but it's likely to take as long to get this to production as it would to just switch to electric cars. I agree that it's still worthwhile to do for the other reasons you suggest, though.
I don't think there's enough CO2 in air (a few hundred ppm) to make this practical. Using the waste gas stream from a coal fired plant (as suggested in TFA) would probably be a better option.
It would be tough to use a thorium reactor to power this. Per TFA, it's more than just getting the ceria to a certain temperature - you have to hit it with light that contains some substantial amount of UV (that's why they had to get to Switzerland - so they could use a solar simulator). I guess you could build a bunch of special light fixtures, and power them with electricity, but... that would likely be pretty expensive. You'd probably be better served to just run the thing during the daytime.
A high oxygen level would make it more feasible for land animals to once again become gigantic. I look forward (in a future incarnation), to hiding from a 50-foot-tall housecat.
It seems like sci-fi, but it's really just simple physics. (Although I don't know if the calculations work out). And it would probably happen a lot faster than millions of years.
. . . because CO is so much better for the environment, and we don't go to any special effort to get rid of it.
Wait, shit.
My sister opened a computer store in Hawaii. She sells C shells by the seashore.
Sure, thorium's fun and all, but if you build a powerful enough solar furnace, surely that's all you really need. Why bother with building another completely different type of furnace to heat the thing at night when you need it to cool down at some point anyway? I hate obnoxious NIMBYism and eco-luddism almost as much as I hate over engineering for the sake of using a pet technology.
I don't therefore I'm not.
Sigh.
... is that you're solving a problem that the Navy doesn't have. For one thing, there's no requirement to be able to recondition your CO2 scrubbers at sea. And the current system for generating O2 and removing CO2 (and other gases - the current system needs to and does remove other stuff) is perfectly serviceable. The only way this ceria based system is ever going to be in contention to replace electrolysis/scrubbing is if it could get the job done at a significantly lower cost - and given that you'd have to do a ton of R&D to get this thing into a deployable state, that seems pretty unlikely.
Doesn't plants "breath" CO2????
Thing I don't get is where does the Co2 come from? If the reactor some how captures it from ambient airflow over the device, then that's *amazing*. But if they actually have to *assume* a good flow of concentrated Co2 from somewhere, isn't that adding to the cost? Sucking Co2 out of the air would become a whole new industry, expensive enough in its own right! And if they are talking about using Co2 captured from some fossil fuel plant, then, ummm, isn't that defeating the whole point? It's still addicted to fossil fuels.