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Earth Power Hardware

New Sunlight Reactor Produces Fuel 269

Posted by CmdrTaco
from the summon-danny-boyle dept.
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."
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New Sunlight Reactor Produces Fuel

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  • by jeffmeden (135043) on Wednesday January 19, 2011 @12:57PM (#34929760) Homepage Journal

    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.

    • by clonan (64380)

      The article said it had a 15% conversion rate.

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

      • by jklovanc (1603149)

        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

    • Or: bottle methane obtained by reacting atmospheric CO2 and H2O, burn in vehicle, return CO2 and H2O to atmosphere. It could provide a higher density energy transportation medium than batteries (and allow for faster refueling as well).
    • by NEDHead (1651195)

      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 ....

      • by wierd_w (1375923)

        Would also enable regenerative atmospheric reprocessing on board a closed-system vehicle, like a submarine or a deep-space spaceship.

        Both would require something ELSE as the main power source, such as a fission or fusion reactor-- Thy CO2 reprocessing that this technology offers would be just to keep the air breathable.

        (In the case of a deep space flight, the CO produced could be rapidly fed to algae to liberate the remaining oxygen, and to produce nutritious algae flakes for your breakfast in the morning.

        • by Nutria (679911)

          Would also enable regenerative atmospheric reprocessing on board a closed-system vehicle, like a submarine

          A 3000o furnace in a submarine?

      • by h4rr4r (612664)

        This solves the Batteries issue. You can burn Methane in your car and this can supply that Methane without all the CO2 and drilling.

  • Loads of Potential (Score:5, Insightful)

    by Philomage (1851668) on Wednesday January 19, 2011 @01:00PM (#34929808)

    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...

    • 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.

  • Headline! (Score:5, Funny)

    by rumblin'rabbit (711865) on Wednesday January 19, 2011 @01:07PM (#34929886) Journal
    World Energy Problems Solved!
    4th Time This Month
  • by dkleinsc (563838) on Wednesday January 19, 2011 @01:09PM (#34929918) Homepage

    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.

    • by nedlohs (1335013)

      The NIMBY crowd will possibly get annoyed with you when try and harvest said resource and when you use it as fuel.

      • by wierd_w (1375923)

        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.)

    • It is however about 1% or less efficient. While these guys are claiming 15% efficient.
  • 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?
    • by geekoid (135745)

      Maybe it's less efficient, but so what? The source is free, so even if it is less effiecnt, if the total energy can be maintained, then it's a wash.

      • by vlm (69642)

        Maybe it's less efficient, but so what? The source is free, so even if it is less effiecnt, if the total energy can be maintained, then it's a wash.

        Welcome to EROEI energy returned on energy invested. Lets say you can build a plant that makes 10 million barrels of crude oil equivalent over its lifetime. If it takes less than 2 million barrels of crude to dig the materials out of the ground, pay the folks whom maintain the plant, and finally pack it in the landfill when its done, you made a profit of 8 million barrels.

        On the other hand, if it takes 20 million barrels of crude to refine the materials, build the plant, maintain the plant, decommission t

        • by h4rr4r (612664)

          Welcome to reality, price of oil is going up, and batteries have not come far enough. This means burning those barrels now to build the plant and selling them later via your plant could make you real money. Even if that is not true, my car can cheaply be made to burn Methane, it cannot cheaply become an electric car.

          • by Arlet (29997)

            If the EROEI is negative, there's no point at all. You'd be better off leaving those barrels in the ground, and use them later.

    • by vlm (69642)

      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?

      Well, best comparison model is probably farming, where your typical crop runs about 1 or 2 percent efficiency from sunlight to glucose but these guys can almost make methane at 15% efficiency. Also fertilizer and insecticide costs are zero and theoretically you can produce whenever the sun is up regardless of outdoor temperature.

      So I'm thinking it would be a bit more capital intensive and much less risky than industrial farming.

      http://en.wikipedia.org/wiki/Photosynthetic_efficiency [wikipedia.org]

  • by 140Mandak262Jamuna (970587) on Wednesday January 19, 2011 @01:17PM (#34930016) Journal
    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: (Score:3, Informative)

      by Anonymous Coward

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

      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).

      • by h4rr4r (612664)

        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.

    • Another rare earth, which China has started rationing to the rest of the world .... [publicbroadcasting.net], as I sit here watching the Chinese president speak from the White House.
    • by vlm (69642) on Wednesday January 19, 2011 @01:40PM (#34930274)

      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.

    • by I8TheWorm (645702) * on Wednesday January 19, 2011 @01:42PM (#34930310) Journal

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

      India, Brazil, USA, Sweden.

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

    • by mcgrew (92797) *

      Cerium [wikipedia.org] is the most abundant of the rare earth elements, making up about 0.0046% of the Earth's crust by weight. It is found in a number of minerals, the most important being monazite and bastnasite. Commercial applications of cerium are numerous. They include catalysts, additives to fuel to reduce emissions and to glass and enamels to change their color. Cerium oxide is an important component of glass polishing powders and phosphors used in screens and fluorescent lamps.

      It was first found in Switzerland an

  • Old News (Score:4, Informative)

    by jklovanc (1603149) on Wednesday January 19, 2011 @01:24PM (#34930102)
    • by Arlet (29997)

      And the efficiency is still extremely poor.

      • by hipp5 (1635263)

        And the efficiency is still extremely poor.

        Who cares what the efficiency is? What matters is the cost:efficiency ratio. As long as it's cheap enough (I have no idea if it is) you can build as many as it takes to make up for the low efficiency. (Note that cost includes land to build them, however much that is).

        • by Arlet (29997)

          Sure, but a poor efficiency is going to make it harder to get a good EROEI ratio.

  • Patent trick (Score:3, Interesting)

    by Iffie (1410897) on Wednesday January 19, 2011 @01:43PM (#34930324)
    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 [greencheck.nl] It shows the patents and the reactions proposed. Supressed technology is reintroduced as an invention. Cerium spiked up 600 perscent last august..
  • CO + 2O2 -> CO2 + O3

    So, we end up with ground level ozone and CO2. Yay.
  • Nuclear (Score:2, Insightful)

    by Charliemopps (1157495)
    "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
  • 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 f

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