Reverse Combustion: Can CO2 Be Turned Back into Fuel? [Video]

Various efforts are underway to find a cheap, efficient and scalable way to recycle the greenhouse gas carbon dioxide back into the hydrocarbons that fuel civilization















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SOLAR FUELS: Using this giant dish made of mirrors, Sandia scientists concentrate sunlight on a specially designed solar-fuel generator that can break down CO2 and water. Image: Photo by Randy Montoya / Sandia National Laboratories

In the 1990s a graduate student named Lin Chao at Princeton University decided to bubble carbon dioxide into an electrochemical cell. Using cathodes made from the element palladium and a catalyst known as pyridinium—a garden variety organic chemical that is a by-product of oil refining—he discovered that applying an electric current would assemble methanol from the CO2. He published his findings in 1994—and no one cared.

But by 2003, Chao's successor in the Princeton lab of chemist Andrew Bocarsly was deeply interested in finding a solution to the growing problem of the CO2 pollution causing global climate change. Graduate student Emily Barton picked up where he left off and, using an electrochemical cell that employs a semiconducting material used in photovoltaic solar cells for one of its electrodes, succeeded in tapping sunlight to transform CO2 into the basic fuel.

"The dominant thinking 10 years ago was that we should bury the CO2. But if you could efficiently convert it into something that we wouldn't have to spend all that money and energy to put into the ground, sort of recycle it, that would be better," Bocarsly says. "We take CO2, water, sunlight and an appropriate catalyst and generate an alcoholic fuel."

He adds: "We didn't have some brilliant insight here. We had some luck." Luck that venture capitalists are now trying to turn into cash flow via a start-up known as Liquid Light.

Turning CO2 into fuels is exactly what photosynthetic organisms have been doing for billions of years, although their fuels tend to be foods, like sugars. Now humans are trying to store the energy in sunlight by making a liquid fuel from CO2 and hydrogen—a prospect that could recycle CO2 emissions and slow down the rapid buildup of such greenhouse gases in the atmosphere. "You take electricity and combine CO2 with hydrogen to make gasoline," explained Arun Majumdar, director of the Advanced Research Projects Agency–Energy (ARPA–e) that is pursuing such technology, at a conference in March. "This is like killing four birds with one stone"—namely, energy security, climate change, the federal deficit and, potentially, unemployment.

"When these new technologies get commercialized, those jobs always end up in the U.S.," argues chemical engineer Alan Weimer of the University of Colorado at Boulder, who is working on such solar-fuel generators. Adds chemist Michael Berman of the U.S. Air Force Office of Scientific Research, which is funding research into the possibilities of solar fuels, including Bocarsly's work: "The country, and the Air Force, need secure and sustainable sources of energy…. Since the sun provides enough energy for our needs, our goal is to make a fuel using CO2 and sunlight—and maybe water—as feedstocks to produce the chemical fuel that can store the sun's energy in a form that we can use where and when we need."

 

Editor's Note (9/24/10): This broadcast stated incorrectly that it takes 18 kilowatts to separate hydrogen and oxygen in one gallon of water. The correct term is kilowatt-hours, a unit of energy. It also incorrectly stated hydrogen and oxygen molecules, rather than atoms, comprise water.



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  1. 1. Shockkburner 02:13 PM 9/23/10

    If you watch the video from 1:44 to 1:50 the narrator says it takes "18 kilowatts (18,000 watts) of energy" to separate the hydrogen from one gallon of water. However a watt is a unit of power (energy over time). Additionally, it is later stated that this "energy" is equivalent to the amount of energy 300 light bulbs expend in one hour. Assuming standard 100 watt incandescent bulbs this equates to 108 mega-joules (108 million joules). So even if they had meant 18 kilo-joules instead of kilowatts they still made a mistake.

    PS. Units are important, just ask NASA (http://www.space.com/missionlaunches/launches/orbiter_errorupd_093099.htm).

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  2. 2. jerryd 03:11 PM 9/23/10


    Several detail are wrong here. For instance both flight and trucking can be fairly easily converted to Electric power by using high speed trains. Both faster and more eff. Trains are faster because they don't have take off, landing, etc problems that take so much time, a slower can actually be faster time wise.

    A train made up of specially designed trucks can be made to use high speed tracks also cutting both fuel use and time to transport. If the truck drivers are onboard they as they arrive just drive off the track to their final destination.

    Of just have E truck lanes with either overhead wires or a third rail and can be on autopilot until is gets where it is going.

    All these are far more eff than liquid fuels and less costly over 15 yrs.

    My EV gets 600mpg equivalent and a similar 3wh 2-3 seat aero cabin EV can go 100 miles and 75mph and be built using 40-100 yr old tech, lead batteries for about $8k. I'd like to see any similar fueled vehicle get anywhere close to that.

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  3. 3. Dilluh 03:30 PM 9/23/10

    Not to nitpick, but it is important to use accurate terminology. The video says that water is made up of two molecules of hydrogen and 1 molecule of oxygen. It should say 2 atoms of hydrogen and 1 atom of oxygen.

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  4. 4. shvegas 03:46 PM 9/23/10

    @shockburner,
    300 60 watt bulbs burning for one hour would be 18,000 watts. Their units seem correct to me.

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  5. 5. Shockkburner 04:21 PM 9/23/10

    @shvegas,
    Well they use kilowatts as a unit of energy (a watt is a unit of power) they probably meant kilowatt hours which according to your calculation works out. My main argument was that they use the wrong unit.

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  6. 6. scohn in reply to Shockkburner 05:37 PM 9/23/10

    I believe that you make an incorrect assumption of using 100 watt bulbs. If instead they used 60watt bulbs (almost as common) we would have:
    18000j/s = 300bulbs x 60watts/bulb = 18000watts (or j/s)

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  7. 7. Shockkburner in reply to scohn 05:47 PM 9/23/10

    Read comment 5.

    "@shvegas,
    Well they use kilowatts as a unit of energy (a watt is a unit of power) they probably meant kilowatt hours which according to your calculation works out. My main argument was that they use the wrong unit."

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  8. 8. Shade1974 06:59 PM 9/23/10

    I think this is great stuff. It means that with enough nuclear plants and renewable energy producers, my grand-children might still be able to fly to visit me on summer vacation. (Hmm... should mention I don't have children, much less grand-children, yet for that to statement to make sense.) Anyway, the point is valid. The technical hurdles of getting our planes in the air with the tech now already relies on the best we could do with no technology restriction, and is pushing a delicate balance to remain economical. If it were any less efficient, any heavier, or any less resistant to cold weather, we probably couldn't keep up the service we have now. This way, even if we run out of oil, we can hook up our grid to a fuel creation station and make enough jet fuel to at least power of fleet of planes. It will cost a little more, but probably not be a deal breaker. I am skeptical of claims that speed trains will be the wave of the future. Planes are something like six times faster than most "bullet" trains. Foreign countries just go around giving their velocities in kph so you'll think they are fast ;).

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  9. 9. jtdwyer 01:18 AM 9/24/10

    I'll ask the dumb question again: if we stop burning all preexisting hydrocarbon fuels and switch entirely to recycled CO2 products: by what percent will our contribution to atmospheric co2 be reduced; how long will it take to return the average global temperature to pre-industrial levels?

    As I understand, massive processes already in progress produce a thermal momentum effect, ensuring that the Earth will continue to warm even if atmospheric co2 was now suddenly returned to pre-industrial levels.

    Not to be too pessimistic, but I suspect the kind of global technological and manufacturing migration that would be required for recycling CO2 currently produced by burning hydrocarbons would take several decades and be largely ineffective.

    The last thing we need to do is spend decades feeling that we're on the right track only to discover it didn't produce the required results. Many billions of people would suffer.

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  10. 10. R.Blakely 01:59 AM 9/24/10

    Great ideas, but carbon dioxide is not causing climate change. The fact is that the gas totally absorbs light only at 15 microns (water vapor absorbs more). This means more carbon dioxide cannot absorb more light to warm the Earth any more. Natural gas and coal are abundant and can be turned into liquid fuels. Solar power can compress air into carbon-fiber tanks to power cars and homes efficiently without pollution.

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  11. 11. KWEBIKE 02:08 AM 9/24/10

    Well, Shockburner and SHVEGAS finally figured out the units, 18,000 kilowatt hours of energy. But everyone has missed the big picture. They stated that it took energy to separate the CO2 from the air but never quantified it. They also never quantified the energy to convert the carbon and hydrogen into methane. Even if they quantified all the energy input required they never talked about how much they would get out of the methane compared to the energy put into it. The big picture is, if they put enough energy to drive an electric truck 100 miles and produce enough methane to drive a truck 10 miles, is this a good use of that input energy, or would the electricity from the windmills be better put to use in an electric vehicle?

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  12. 12. Dr. Strangelove 04:54 AM 9/24/10

    What's the point of converting sunlight to hydrocarbons before using them for electricity and transport? To get energy out of it, you have to burn them and release CO2. Solar cells can generate electricity directly without CO2 emission. They can be used for transportation too via solar cars and electric cars recharged by grid electricity from solar cells. Hydrocarbons and internal combustion engines are an old paradigm. Solar cells and electric cars are the future.

    But if you wish to stick to hydrocarbons, the artificial method of producing them, such as the CR5, is expensive and unreliable so far. Why not just do it the natural way, biofuels, which is cheaper and already mass produced? Sure, plants are less efficient in converting sunlight to chemical energy, 3-6% versus 6-20% for solar cells. But one sq.m. of leaves is a lot cheaper than one sq.m. of photovoltaic cells. Sugar cane is still more cost efficient than CR5.

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  13. 13. Iggle 08:27 AM 9/24/10

    Wow, great stuff. If only there were a natural process that used solar energy to remove CO2 from the air, utilized water from the ground and converted it all into something harmless like O2 and maybe some other useful substance like wood or grain or something. We would "seed" this natural process all over the earth.

    (to be fair, I only watched the silly video...didn't read the article)

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  14. 14. jtdwyer in reply to Iggle 11:01 AM 9/24/10

    Yeah, but with the video you always get the happy ending...

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  15. 15. Shade1974 in reply to R.Blakely 11:56 AM 9/24/10

    In response to R.Blakely on Carbon dioxide not being responsible for climate change because water vapor absorbs more light: I don't really know the specifics here, but my understanding was that carbon dioxide is transparent in the visible light frequencies, which is part of the problem. It happily allows visible light from the sun to make it to the surface. What it prevents is the radiation of the thermal energy from the earth back out into space. Think if it as wrapping yourself in transparent plastic and sitting out in the sun.

    Water behaves in lots of different ways. In the form of water in the oceans, it is one of the most fantastic absorbers of electromagnetic wavelengths available. As humidity in the atmosphere, it increases the amount of energy that the atmosphere absorbs and transfers into thermal heat, as opposed to letting the ground absorb the same energy and turn it into heat or reflect it. This reduces the visible light we reflect back into space, but because most of our planet is covered in oceans, the visible radiation absorbed from light reflected from the ground is less important for energy dissipation than being able to radiate in the thermal bands. Even the oceans radiate in that part of the spectrum.

    As Ice, water is extremely reflective. You also don't have a lot of humidity where it's cold enough to have ice. The problem with ice is that as the planet warms, its cooling influence on our temperature decreases because there is less of it. So at least at the outset of climate change (regardless of the cause) the recession of glaciers and ice layers causes more and more energy to be trapped by the ground and water where the ice used to be, increasing the temperature.

    As cloud cover, however, the most energy filled wavelengths across the visible spectrum are reflected by Mie Scattering. This effect actually helps us. If the cloud cover around the world increases as a result of the warming climate, this may help to regulate our temperature eventually. In the long term picture, assuming there are no other influences I'm forgetting, once we run out of ice, eventually the cloud layers will get so thick that our temperature should level off, even with a higher carbon dioxide level. It's just that the side-effects of this change are pretty bad and we should probably be planning for them.

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  16. 16. jtdwyer 12:27 PM 9/24/10

    The article states:
    ""You take electricity and combine CO2 with hydrogen to make gasoline," explained Arun Majumdar, director of the Advanced Research Projects Agency–Energy (ARPA–e) that is pursuing such technology, at a conference in March. "This is like killing four birds with one stone"—namely, energy security, climate change, the federal deficit and, potentially, unemployment."

    How can this monumental industrial migration to co2 recycling technology possibly be expected to solve global warming? Even optimistic technical assessments describe this as an interim solution.

    These people are attempting to mortgage the future of humanity by selling what cannot be delivered. Could this be another Wall Street financial marketing scam? What an opportunity!

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  17. 17. GoatGuy 12:36 PM 9/24/10

    Hey folks...

    SHOCKBURNER is right - kilowatts are measures of energy-delivery-rate, not the summation of energy-used-to-accomplish-some-quantitative-goal.

    Second, "2 molecules to 1 molecule" is just as acceptable as "2 atoms to 1 atom".

    Third, this technology's proponents strike me as having the credibility of Mayan Shamans standing on a pyramid shaking feathered fetishes at the oncoming hurricane! Without (gu)estimating the scale of a significant-fraction-of-power-use delivery vehicle... this is just a feathered fetish. Yes, picture(s) of tiny little men in front of great honkin' mirrors makes the kiddie-scientists go Oooh, Ahhh. But realistically? Millions of square kilometers of mirrors and trillions of dollars of investment, and hundreds of millions of jobs to mine, smelt, melt, mould, fabricate, install and maintain the great mirrored edifices?

    No, let's just admit - out loud - that these great science projects and research experiments are feathered fetishes, equal in their proportionate value to casting aside the oncoming hurricane as were the Mayan Shamans.

    Really. I'm not even being sarcastic.

    GoatGuy

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  18. 18. Loubarouba 01:08 PM 9/24/10

    First totally agree with Goat Guy
    Second this doesn't reduce CO2 from the atmosphere it just slows the rate at which it increases albeit very poorly if at all. Not only would so much energy be wasted in converting the co2 to methane but also the gasoline powered engine is ill designed to begin with for the amount of energy going in, too much energy is lost in heat, it's not nearly efficient enough. The whole idea is ludicrous it'd be like paying your friend 10 dollars so you can get back 1..if that.
    Yeah this technology would be great if we actually had a net gain in energy but this attempt at reducing CO2 in the air while giving us a fuel source is totally ridiculous. The idea to hit two birds with one stone is good but once it goes on paper, it will be utterly retarded. The total CO2 just to create/transport/setup the solar panel itself is probably more than what it would take out of the atmosphere, especially since solar panels degrade over time.
    I say just turn the CO2 into chalk (calcium carbonate) until we find a real way (efficient) to turn CO2 into an energy source. Use the solar panels and wind turbines to offset the coal powered power plants, and save all the liquid and gas combustibles for our automotive fleet and housing needs, until our battery tech catches up (energy/dollar wise).

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  19. 19. jtdwyer in reply to Loubarouba 04:51 PM 9/24/10

    I agree with you, including the mineral sequestration of co2 as the only way to possibly halt global warming. However, aren't there some rather common conditions that might might cause the 'chalk' (or whatever mineral) to catastrophically release its sequestered co2?

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  20. 20. Chris G 05:30 PM 9/24/10

    The problem with biofuels is that they don't really produce much of a net gain in energy by the time you factor in the production costs. Plus, we barely have enough food to feed the world now; converting food to energy is not going to be good for the poorer portion of the population.

    There are conditions in which a fuel stable at atmosphere pressure and normal temperatures is more efficient than hydrogen, and batteries.

    I don't think that the point of this article is that this is _the_ solution. I think the point is that this is an interesting technology that may help. Are the inventors excited about it? Sure, but then so is the inventor of most things

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  21. 21. jack.123 07:14 PM 9/24/10

    Sometime in the next 10,000 years,maybe next year the next ice age will begin.Global warming will then be something people want instead of trying to get rid of it.Lets hope all this reduction of greenhouse gases that half the world is trying to do doesn't in fact trigger the next ice age.

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  22. 22. jtdwyer in reply to Chris G 08:37 PM 9/24/10

    I agree that the inventor see this as an interim solution.

    However, Arun Majumdar, director of the Advanced Research Projects Agency - Energy (ARPA-e) is quoted as saying:

    "This is like killing four birds with one stone" - namely, energy security, climate change, the federal deficit and, potentially, unemployment."

    Doesn't this sound like the pitch men are selling this to the politicians and potential investors as _THE_ Solution? It doesn't sound like anything else to me.

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  23. 23. Elena Ornig 10:03 PM 9/24/10

    Hi to everyone,
    I would like to bring to your attention something I have just recently get involved in. On my website Peal People Real Answers (com.au) I had published papers of Australian engineer who challenges everybody to prove him wrong or right in his invention that might result in new source of cheap energy. He said that he doesn't want money-he wants answers. His papers,calculations and actual design are very convincing but I am not scientist. If all of you care so much for better ways to provide energy for the world I though you might be interested to look at his publications or maybe even take his challenge on. For any questions about his papers you can contact him directly through our website.

    Warmest regards

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  24. 24. Ungolythe in reply to jack.123 10:25 PM 9/24/10

    The goal is to reduce the amount of greenhouse gases the we pump into air in quantity more so than to reduce them. Even though I don't wish to live through an ice age if we could somehow prevent them from ever happening again I'm not so sure this would be a good idea.

    I agree with jtdwyer that the last part is overstated. It would be more correct in saying that the technology could help kill help kill 4 birds with one stone. Whether or not it is successful or not is a matter of economics. If it has to use as much electricity that it would take to drive a truck for 100 miles while only producing enough fuel to propel it 10 miles I can't see that it would ever be successful regardless of the amount of the research money from the venture capitalists.

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  25. 25. NICKTAZ 12:04 AM 9/25/10

    Let's talk politics for a moment. The world's governments will NEVER allow for a new technology that will plunge huge swaths of the planet into economic disaster-- Far from a humanitarian effort, the world is less safe when a region such as the middle-east(An oil based economy)becomes dozens of times worse than it already is. This is one of the factors that slows government investment into an industry so large that only government can provide the funds needed to yield real change.

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  26. 26. jtdwyer in reply to NICKTAZ 01:57 AM 9/26/10

    In my opinion, each of the world's governments will take any action that most expediently satisfies high priority political objectives, particularly if there is potential for personal gain. That's how they do what they do.

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  27. 27. candide 12:24 PM 9/26/10

    "I would feel more optimistic about a bright future for man if he spent less time proving that he can outwit Nature and more time tasting her sweetness and respecting her seniority."

    - E. B. White

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  28. 28. R.Blakely in reply to Shade1974 02:56 AM 9/27/10

    R.Blakely in response to Shad1974 comment, the fact is that water vapor absorbs all infrared at 4 microns. The other important fact is that carbon dioxide already absorbs all the infrared it can. This is at 15 microns. Carbon dioxide cannot absorb any more infrared. So, more carbon dioxide cannot cause more global warming. Therefore, carbon dioxide has no effect on climate.

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  29. 29. Chris G in reply to R.Blakely 10:31 AM 9/27/10

    28. R.Blakely,

    You are referring to the saturation argument. A few questions for you:

    A) At what altitude do you think CO2 is saturated in terms of energy absorption? Is it saturated at 5 km, 10 km, 20 km, other? The atmosphere is not of uniform density, you know.

    B) What happens to the energy that a CO2 molecule absorbs? Do you think in simply ceases to exist, or do you think it might be radiated again?

    C) How much water vapor is there above the tropopause?

    More on the saturation argument at

    http://www.skepticalscience.com/argument.php

    #54

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  30. 30. GoatGuy in reply to Elena Ornig 04:06 PM 9/27/10

    I appreciate your enthusiasm for promoting the "Perpetual Magnetic Motion" PDF. The fellow postulates that his calculations are correct, that there is an integrated net "positive" force that over distance (or in the case of a wheel, around the circular integral of its 360°motion), when both attractive and repulsive forces are summed.

    The physics answer as to why this cannot work is simple: on any closed path through any magnetic-electrical field, any charged particle or object with a magnetic moment experiences a NET integrated force of exactly zero. Not a fillip more or less.

    In particular, I guide you to the second Maxell's equation in this graphic:

    http://elementaryteacher.files.wordpress.com/2008/08/maxwells-equations.gif

    It means that a circular-path integral through a magnetic field (which does not have to be uniform), is precisely defined has having ZERO net force, or to put it a different way, that magnetic attraction and repulsion is a model for the PERFECT SPRING.

    Therefore, the researcher's Perpetual Magnetic Motion idea's calculations that result in a huge positive force around the circular integral of either a single set of magnets, or the wheel's worth ... is in error in terms of the circular integral of magnetic moment itself. Many a young scientist is intrigued by the force-over-distance of magnets, and dreams of harnessing the seemingly limitless power of the magnet to produce endless energy. Unfortunately, Maxwell's Second Equation is the killer to ALL such attempts.

    Best Wishes, GoatGuy.

    PS: the author demonstrates a certain innocent ignorance of physics by posing the question, "but why can't one hang onto a playground monkeybar upside down without fatigue?" (heavily paraphrased). The answer is entirely different to the analogy of the magnet-on-the-ceiling. One's muscles DO expend significant energy to maintain force, whether they are in motion or not. Electrochemical force comes at great resistive cost to the muscle: the researcher should try imagining a car on a steep hill, with no brakes, but a manual transmission. Letting the engine run, and the clutch slip, one can remain pretty steady. However, the clutch will also burn out rapidly from overheating. Same mechanism as the high-force muscle, that happens to be at rest.

    GoatGuy

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  31. 31. Joseph C Moore, Cpo USN Ret in reply to R.Blakely 04:50 PM 9/28/10

    Absolutely! The global warming idiots do not have a real, viable solution to their perceived problem.

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  32. 32. 2008RealityCheck 05:59 PM 9/28/10

    Before considering sequestering concentrations, what ppm of CO2 are you seeking? You may find the cure worse than the problem.

    CO2 is a finite resource that has been decreasing in supply for 700 million years.

    7000 ppm is what Earth had 540 million years ago.

    250 ppm is what Earth dropped to before the industrial revolution. Most carbon had been sequestered underground, inaccessible to the biosphere.

    150 ppm is the point where nearly all plants on Earth DIE.

    350 ppm is where we're at right now. The higher the concentration, the better plants grow. That is a FACT.

    Methane is 28 times more effective than CO2 as a global warming gas, yet is mostly ignored in the discussion. So why isn't Scientific America focusing on how to prevent methane from escaping, or in reducing methane production in manmade and natural resources?

    Do you realize that Congress blocked the use of biomass from National Forests, and this biomass now will rot and release massive quantities of methane? If biomass were harvested and used for product or biomass burning for fuel, it would be converted directly to CO2 and thus present reduced overall global warming effect?

    Sequestering CO2 underground takes about 20% of the power plants power.

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  33. 33. 2008RealityCheck 06:01 PM 9/28/10

    Before considering sequestering concentrations, what ppm of CO2 are you seeking? You may find the cure worse than the problem.

    CO2 is a finite resource that has been decreasing in supply for 700 million years.

    7000 ppm is what Earth had 540 million years ago.

    250 ppm is what Earth dropped to before the industrial revolution. Most carbon had been sequestered underground, inaccessible to the biosphere.

    150 ppm is the point where nearly all plants on Earth DIE.

    350 ppm is where we're at right now. The higher the concentration, the better plants grow. That is a FACT. Are you sure you want to lower CO2, and not focus on methane?

    Methane is 28 times more effective than CO2 as a global warming gas, yet is mostly ignored in the discussion. So why isn't Scientific America focusing on how to prevent methane from escaping, or in reducing methane production in manmade and natural resources?

    Do you realize that Congress blocked the use of biomass from National Forests, and this biomass now will rot and release massive quantities of methane? If biomass were harvested and used for product or biomass burning for fuel, it would be converted directly to CO2 and thus present reduced overall global warming effect?

    Sequestering CO2 underground takes about 20% of the power plants power.

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  34. 34. CaliforniaJoe in reply to jerryd 04:41 PM 10/4/10

    I knew a man who worked as a mechanic for Railway Express in Manhattan in the 1940s, and he told me that at that time there were thousands of EV delivery trucks being used for cargo delivery. He said that their use had been mandated, that they used lead-acid batteries, and that whenever possible they worked at night to avoid traffic.

    The point is that using lead-acid batteries for transportation has been done before, but it is seldom if ever mentioned.

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  35. 35. CaliforniaJoe in reply to jtdwyer 04:50 PM 10/4/10

    According to the "Climate Institute", the natural half life of carbon dioxide in the atmosphere is about 100 years, unless we start actively removing CO2.
    They state that the level of CO2 in the atmosphere has risen by about 30% since the start of the industrial revolution, and that CO2 is currently at the highest levels that it has been in the past 150,000 years.

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  36. 36. Jim Bullis, Miastrada Company 03:36 PM 10/15/10

    This is a sad representation of science and engineering.

    We discover that electricity can be used to make hydrogen and oxygen from water. Things get better, electricity can be used to make methane out of carbon dioxide and hydrogen. We also learn (with great mental exertion) that it takes 18 kWhr to make the hydrogen and oxygen from a gallon of water. Then we credit Palo Alto Research Center with the idea that electricity can come from renewable energy.

    Wow, that is fine science!

    Oops. But it seems the report is numerically challenged, since we fail to report how much electricity would be required to turn the hydrogen and CO2 into methane. So we are nowhere. And are we serious? The 350 ppm of CO2 in air is going to be a source for this industrial process?

    Pablum would be fine, but all of this stands in the way of real progress.

    Standing Forests Solve Global Warming At No Cost

    The game winning answer to global warming is to create standing forests, where every ton of newly existing forest mass, on a sustaining basis, compensates by CO2 capture for the burning of a ton of coal, approximately. Key to this solution is distribution of water in North America on a continental basis.

    Existing electric power demand and new electric vehicles present a significant and growing CO2 problem. Viable, large scale solutions to this problem have been absent. But I have been shocked by the planning put forward by the US EPA regarding 'carbon' capture and sequestration (CCS), where the capture cost burden per ton of coal used would be up to $180-$320. This would be for capture of CO2 only, with additional costs for transportation and pumping it into caverns being not addressed, but acknowledged as additional expense.

    Thus motivated, I looked for a better solution, and found that China seems to have taken the lead over our environmentalists in this very practical matter. A year ago, in a speech about how China was planning to react to the global warming problem, President Hu spoke of "forest carbon".

    This kind of solution would be possible in North America. The key is to change how water is distributed on this continent and use it to establish new standing forests that would achieve CCS.

    Thus, a real answer to global warming is possible that would enable continued use of our backbone fuel, that is coal, for generation of electricity.

    Thus with cheap energy, industrial expansion could be ecomically justified and job creation could then begin.

    We could stop pretending that renewables will appear on a meaningful scale.

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  37. 37. Tofara 08:33 PM 10/31/10

    The greenhouse effect of carbon dioxide is not just from it's absorption of light but from its absorption of heat.

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  38. 38. SigmaEyes 09:47 PM 4/2/11

    So, I assume it might be ok to pass a carbon tax if we can use this technology to put inside an industrial air pollution "scrubber" equipped with solar cells on the outside. (they already have water and CO2 on the inside). Would that mean we would continue to burn coal for electricity? Capitalism never seems to work out the way environmentalists envision.

    Pulling co2 out of coal fire smokestacks still leaves many toxic pollutants to escape to the atmosphere, even if the proposed carbon tax is implemented, but avoided.

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  39. 39. haruspex 05:02 PM 11/23/11

    Sadly, there is a fatal flaw in the idea of using this as an alternative to burying CO2. The GHG problem is not that we do things which release CO2 into the atmosphere. There is a huge natural cycle which does that already. The problem is that we're adding carbon to that cycle that had been safely sequestered underground.
    If we burn coal, capture the CO2, and convert that to fuel or cattlefeed using algae, then when the product consumed the CO2 still ends up in the atmosphere. All we will have achieved (at best) is a single re-use. Overall, we're still adding to the bioatmospheric carbon cycle.
    Perhaps, one day, algal capture will become economic using CO2 extracted from the air. Until then, this is not the solution we need.

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  40. 40. Newfiegeo in reply to jtdwyer 06:21 PM 6/14/12

    Our contribution will not be reduced.... it will remain at whatever level was in place at the time we switch to recycled fuels. Of course this assumes that we switch 100% instantaneously which will never happen.

    Great idea but sounds very inefficient. Perhaps I'm wrong. The great thing about this is that it demonstrates that people are realy thinking about solutions! I believe we will find one or even several (if they haven't been found already)that will make sense on all levels. Actually, if you think about it, if this source has been found already then there is very little chance that we will hear about - Imagine the advantage a company would have if it found a viable alternative to our current need for fossil fuels. This company would become the most powerfull company in the world - I call that motive to develop in secret!
    I also believe that storage via liquid fuels is a great way to go. These fuels are awesome for so many reasons and there is currently no other energy source as light weight and packed full of energy as these liquid fuels! Plus we have the infrastructure to handle such fuels already in place!

    Cheers!

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