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Post-Combustion CO2 Capture to Mitigate Climate Change: Separation Costs Energy

The views expressed are those of the author and are not necessarily those of Scientific American.

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An astounding variety of data supports the conclusion that our earth’s climate is changing due to increasing greenhouse gas (GHG) concentrations in the atmosphere. The economic, social, and environmental implications could be catastrophic. Moreover, scientists have reached a consensus that the increase in GHGs is indeed anthropogenic, caused by fossil fuel burning and deforestation. Carbon dioxide (CO2) is the GHG that contributes the most to climate change because of both its abundance and long atmospheric lifetime. With the rapid economic development of China (the world’s leading CO2 emitter) and India’s increasing energy demands, the rate of CO2 emissions is accelerating, leaving politicians, scientists, and engineers with an international problem of an enormous scale.

More long-term technological development is required to substantially shift to renewable energy sources that do not emit CO2. Thus, short-term solutions are being considered that enable us to continue using fossil fuels. At present, coal-burning power plants provide 42% of electricity in the US, but at the expense of accounting for ~36% of US CO2 emissions. Among a portfolio of strategies to mitigate anthropogenic CO2 emissions, one high-impact option is carbon capture and storage (CCS). The idea is to capture the CO2 from the flue gas emitted from the smokestacks of coal-burning power plants and subsequently store it underground in a geological formation. The geological formation can be thought of as a sponge for CO2, sequestering it from the atmosphere where it would, otherwise, instigate global warming.

An advantage of the CCS process is that it can in principle be retrofitted to existing coal power plants. A coal power plant retires after a long 45 years of use; a plant built today will, if left unchecked, continue to emit CO2 for 45 years coming. The economics of completely abandoning a prodigious investment in a young plant to curb CO2 emissions are unfeasible. CCS technologies are attractive because they can prevent climate change while protecting current investments.

Already, commercial-scale CCS technologies are in operation, but not at the scale of a large coal power plant. Its market-readiness for mass-adoption is complicated by two broad issues. The first issue is related to the tremendous rate of CO2 emissions. A back-of-the-envelope calculation reveals that the US alone releases from its coal-burning power plants enough CO2 to fill the Empire State Building 100 times every hour. Even given the magic chemical or material that captures CO2 from the flue gas, imagine how much of it we would need. The second issue is that the CCS process places a parasitic energy load on the plant, and that is the focus of this article. The most energetically intensive part of the CCS scheme is capturing the CO2 from the flue gas, separating it from the other components mainly nitrogen (- then why even separate the CO2? – see Note below) Capture technologies at present are estimated to cost 25-30% of a plant’s power output, driving up the price of electricity by around 80%.

Fig 1: The minimum energy to separate the CO2 per mole of CO2 from an ideal gas mixture at room temperature. The minimum energy requirement depends on the concentration of CO2 in the starting mixture.

Fig 1: The minimum energy to separate the CO2 per mole of CO2 from an ideal gas mixture at room temperature. The minimum energy requirement depends on the concentration of CO2 in the starting mixture.

Can we improve capture technologies to reduce the energy costs for separating CO2 from the flue gas? The laws of thermodynamics allow us to calculate the minimum theoretical energy requirement for the separation of the CO2 from the flue gas. That is, the same thermodynamic laws that preclude the construction of a perpetual motion machine say that, no matter how ingenious of a capture process we design, there will always be an energy cost for separating the CO2 from the flue gas. Fig 1 shows a plot of the minimum energy required (per mole of CO2) to separate the CO2 from an ideal gas mixture as a function of the CO2 concentration in the starting mixture. As a sanity check, note that a mixture that is already pure CO2 takes zero energy to separate. For the flue gas from a coal-burning power plant, the CO2 concentration is ~13 mol %, and the minimum theoretical energy requirement from the graph (green dot) turns out to be ~5% of the output of the coal power plant, suggesting that there is room for improvement in current carbon capture technologies.

One might ask, instead, why not just capture CO2 from the very air we breathe? Fig 1 shows that, as the fraction of CO2 in the mixture decreases, we need more and more energy to separate it from the mixture. The CO2 concentration in the air is a measly 0.039 mol % (red dot), rendering energy costs for a separation from air four times that of a separation performed on the flue gas from a coal power plant– even if we were to develop the most efficient separation process nature allows. Another reason to avoid separating CO2 from air is that, for every liter of CO2 to be recovered from the atmosphere, 2500 liters of air must be processed. This excessive air flow rate through a capture process and the increased separation energy costs for such a small CO2 concentration in the air lead to the following conclusion. Procrastinating CCS on coal power plants and instead resolving to capture CO2 out of the the air we breathe– after the flue gas mixes with the atmosphere– will lead to larger separation costs in the future. This is important to consider given that a CO2 molecule released today will stay in the atmosphere for a time comparable to our life span, absorbing sunlight and warming our planet throughout the entire duration.

Fig 2: The entropy of mixing for a system at constant temperature and pressure is the entropy change going from state 1 to state 2. In carbon capture, we want to go from state 2 to state 1, where the red spheres represent CO2 molecules and the blue spheres represent all other molecules in the flue gas. State 1 and 2 are at the same temperature and pressure.

Fig 2: The entropy of mixing for a system at constant temperature and pressure is the entropy change going from state 1 to state 2. In carbon capture, we want to go from state 2 to state 1, where the red spheres represent CO2 molecules and the blue spheres represent all other molecules in the flue gas. State 1 and 2 are at the same temperature and pressure.

The separation energy requirement stems from the tendency of all physical systems to increase a mathematical quantity called entropy; an intuitive, qualitative definition of entropy is “disorder”. The second law of thermodynamics states that an isolated system will maximize its disorder. Fig 2 shows an isolated system (the black box) containing the flue gas in two disparate states (both at the same temperature and pressure). CO2 molecules are depicted as red spheres, whereas all other components of the flue gas are depicted as blue spheres. In state 1, a barrier exists that separates CO2 molecules from the rest. If we remove the barrier, the second law tells us that CO2 will spontaneously mix with the other components, entering state 2, without the help of some outside influence. Because each of the molecules can now explore a greater volume, the disorder of the system has increased, as nature prefers.

In carbon capture, we are starting off in state 2, and we desire to move to state 1. Unfortunate for CCS, going from state 2 to state 1 involves a decrease in disorder (entropy), and this will not happen spontaneously without some outside influence. That is, isolated physical systems tend to maximize their entropy, and if we want to decrease a system’s entropy, we must input energy into the system. In the context of carbon capture, if we want to separate the CO2 from the flue gas, it is inevitably going to cost energy. The laws of thermodynamics allow us to calculate the minimum energy requirement by considering a reversible process from state 2 to state 1, and this is a lower bound– for the most efficient, ingenious process yet-to-be-discovered.

The utility of the entropy of mixing concept is to check how much more progress we can possibly make with capture technology and set realistic targets. The conclusion is that there is room for improvement, but CCS technologies will inevitably incur a sizeable parasitic energy cost on a coal-fired power plant. Since the energy cost is a decreasing function of the concentration of CO2 in the starting mixture (Fig 1), we see the energetic benefits of capturing CO2 from coal power plants now, rather than later, after it mixes in the air.

——- The math behind the generation of Fig 1 for those interested —-


Note: If capturing the CO2 out of the flue gas is the most expensive part, why do we need to separate the CO2 from the flue stream? Why not just pump the entire flue gas stream into the geological reservoir? Well, fortunately, CO2 can be compressed into a supercritical fluid at a reasonable pressure and temperature, endowing it with liquid-like densities and gas-like viscosities– both ideal properties for it to be transported and pumped underground relatively easily. The most obvious reason for not sending the entire flue gas underground is that ~13% of the flue gas stream is CO2, so, even assuming that the other components of the flue gas have exactly the same desirable properties as CO2, storing the entire flue stream requires 7-8 times of (i) the volume of the storage reservoir and (ii) compression and pumping throughput for transporting the flue gas underground. However, the other flue gas components do not have nearly as desirable properties as CO2, and the compression, pumping, and subsequent storage of these components would impose enormous energy costs that make storing the entire flue gas stream unfeasible. Furthermore, a key idea with geological sequestration is that the CO2 will undergo chemical reactions with minerals in the geological formation and, after thousands of years, turn into a mineral. At this point, the CO2 has zero probability of escaping back into the atmosphere. Nitrogen, on the other hand, is too inert to react and form minerals.

** The idea for this blog post came from a course I am taking at Berkeley titled “Carbon Capture and Sequestration”. An interactive iBook is coming soon: Berkeley Lectures on Energy: Carbon Capture and Sequestration by Berend Smit, Jeffrey Reimer, Curt Oldenburg, and Ian Bourg.

A Brown and B Freeman. Analysis and Status of Post-Combustion Carbon Dioxide Capture Technologies. Environmental Science and Technology. (2011) 45 (20), pp 8624–8632.

Smith, Van Ness, and Abbott. Introduction to Chemical Engineering Thermodynamics.

Sponge analogy for a geological formation:

Cory Simon About the Author: Cory Simon is a Ph.D. student in the Department of Chemical and Biomolecular Engineering at the University of California, Berkeley. Cory’s research involves computer simulations of statistical mechanical models to design/identify suitable nanoporous materials for use as sorbents in gas separation and storage applications.

The views expressed are those of the author and are not necessarily those of Scientific American.

Comments 43 Comments

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  1. 1. Sisko 10:45 am 03/7/2013

    The writer of the post shows their obvious bias on the topic of climate change when writing “The economic, social, and environmental implications could be catastrophic.”

    Since we have very little reliable data regarding changing conditions as a result of increased CO2 it would also be equally true to state that conditions may improve as a result of additional CO2. We simply do not know.

    The writer is accurate to state that climate mitigation strategies are generally highly inefficient and not a cost effective use of resources.

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  2. 2. jsalsman 10:57 am 03/7/2013

    Does describe the most cost-effective process so far? Or is cheaper?

    (@Sisko, in what universe do “we have very little reliable data regarding changing conditions as a result of increased CO2″?)

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  3. 3. sault 11:04 am 03/7/2013

    The cheapest way to sequester carbon is to leave fossil fuels in the ground. And I’m sorry but the investors that put down money into coal power plants, Tar Sands extraction, or other activities that emit a lot of carbon over the last 20 years either knew what they were getting into or were too oblivious to reality to deserve keeping their investment afloat. If they knew about the conclusions of climate science, then they entered these projects knowing that they would have to fool the public for a few decades, spreding misinformation about climate science to keep their returns pouring in for as long as possible. Either way, it’s hard to feel sympathetic for them. It’s also sad that a lot of institutional investors have a lot of money tied up in dirty infrastructure, but there is a growing divestment movement that is pulling billion$$$ out of these climate-disrupting projects.

    So if we throw bad money after worse and build up these CCS schemes, we’ll have to mine 30% more coal and the $100B – $500B in YEARLY damages that coal pollution causes would be bumped up as well (coal is only cheap because it’s ALLOWED to be dirty!). Then, just to capture the 2.16Gt of CO2 emissions that coal plants release every year in the U.S. alone would require the movement of around 23 BILLION BARRELS of liquid CO2 into the ground every year! For comparison, the USA consumes 7.3 billion barrels of oil a year…and this is 3x as much!!! Then you have to worry about WHERE to store all that CO2 so that it won’t leak out EVER because it can pool in low-lying areas and in people’s houses, killing them in their sleep.

    I have a better idea. Lets FORCE existing coal power plants to have the best mercury, ash, soot, NOx, etc. pollution controls available, no exceptions, no grandfathering, no nothing! These plants have been able to offload the costs of their pollution and laugh all the way to the bank for FAR too long. If a plant can’t clean up its act, then it’ll have to shut down. We could also reform leasing auctions on federal lands so mining companies can’t game the system, giving around $1B a year in unfair gains back to the government and partially eliminating the artificial cheapness of coal further.

    So we’ll save hundreds of billion$$$ in healthcare costs, have increased worker productivity and less sick days, and less people will have their lives cut short due to less pollution from coal. And we’ll save billion$$$ more by not pursuing carbon capture and storage, something that would instead lock us into even MORE coal pollution for decades. With all these savings, we could maximize investments in energy efficiency, renewables and advanced nuclear power. One approach locks us into a downward spiral of more pollution and suffering while the other approach gives us more diversity in our energy supply and a more prosperous future. Oh, and CCS CANNOT scale up to any meaningful CO2 reductions level anyway, so there’s that too. Numbers don’t lie, and neither should we lie to ourselves that CCS will actually be useful.

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  4. 4. sault 11:23 am 03/7/2013


    And you STILL wonder why people call you a DENIER? Are you in denial about your denial? Just read a scientific paper or two on climate science if you think there’s “very little[sic] reliable data regarding changing conditions as a result of increased CO2…” Or better yet, I’m STILL waiting for ANY of you deniers to post EVEN ONE scientific paper showing that climate change won’t be bad. How long do I have to wait?

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  5. 5. dkahn400 11:40 am 03/7/2013

    Sisko. ‘The writer of the post shows their obvious bias on the topic of climate change when writing “The economic, social, and environmental implications could be catastrophic.”’

    Even accepting your disingenuous conjecture that “conditions may improve as a result of additional CO2″ it is self evident that they could be catastrophic. And of course the overwhelming scientific consensus is that they will be.

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  6. 6. RSchmidt 11:49 am 03/7/2013

    Fossil fuels are only cheap because we don’t pay the full cost. Once we factor in a target of zero emissions the price goes up significantly. We have developed an addiction to heavily subsidized energy, paid for by our children and their children, so we now feel entitled to it. Whenever you hear of new energy sources they always compare them to fossil fuels which is ridiculous when the price of fossil fuels isn’t the real cost of fossil fuels. Solar, Wind and MSRs are where we need to be investing, not in trying to prolong fossil energy.

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  7. 7. Sisko 11:55 am 03/7/2013


    There is absolutely no scientific consensus regarding what rate the planet will actually warm or what will be the net impacts positive or negative as a result of any changes in the climate. That is simply a fact.

    I agree that someone can describe the changes as catastrophic but the word is subject to an individual’s perspective. Some may think it is catastrophic if a single area that they live in is negatively impacted, but that does not mean the perspective includes the net impacts overall. Some countries may be negatively impacted while others benefit.

    Sault- You are the one who has called me the prejudiced term “denier”. You are also the one who has denied the science. We do not have reliable information regarding future conditions.

    You do this in spite of acknowledging that what I have written to be accurate. You have previously acknowledged that we do not know how conditions will change at any specific region or how much they will change over time. We do not know how the key conditions that will impact humans lives will change(annual rainfall as a key example)

    I am not your personal google.

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  8. 8. Sisko 11:58 am 03/7/2013


    Who is the “we” you refer to? Does it include the 3 billion people who want access to electricity and personal transportation?

    Do you believe that there people have no right to electricity or personal transportation? How do you plan to stop other independent nations from doing what they believe is in the best interests of their populations?

    Please try to stop trying to spread inaccurate propaganda and be realistic.

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  9. 9. RSchmidt 12:04 pm 03/7/2013

    @Sisko, you are a pathological denier. You have been given the evidence over and over yet you continue to spread the same lies. You are nothing more than a fossil fuel shill who is paid to troll blogs for articles on AGW. Just another sociopath gladly willing to line their pockets regardless of how much it hurts those around them. When the flood comes, I hope you are living on low ground.

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  10. 10. singing flea 12:07 pm 03/7/2013

    “There is absolutely no scientific consensus regarding what rate the planet will actually warm or what will be the net impacts positive or negative as a result of any changes in the climate. That is simply a fact.”

    What difference does it make what the rate is? That’s like saying you are dying of cancer but don’t know how long you have to live.

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  11. 11. singing flea 12:14 pm 03/7/2013

    “You are nothing more than a fossil fuel shill who is paid to troll blogs for articles on AGW. ”

    Considering that half the country voted for G.W. Bush twice over failed oil policies, it is not a fair conclusion that they are all paid shills. It is a fair observation that where ignorance is bliss, it is folly to be wise.

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  12. 12. lamorpa 12:20 pm 03/7/2013


    There was a time when people would engage in attempt to enlighten those such as yourself to simple scientific realities and worldwide trends that unequivocally demonstrate the reality of human activity induced climate change. That time is over. You are now simply snickered at like the proverbial conspiracy theorist wearing a tin foil hat. Sorry.

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  13. 13. Sisko 12:41 pm 03/7/2013

    Please try to point out anything that I have written above that is not accurate. Be specific please.

    Flea. –

    The rate of any warming is a very important part of the overall issue because a higher rate of warming means that there is additional risk of life having difficulty in adapting to changing conditions. Your comparison to getting cancer is not accurate since changing conditions are not necessarily harmful. If it were to warm slowly there is very risk of substantial harm to humanity as people would adjust to the changing conditions over multiple generations. We know that the climatic conditions will always change over time. One of the large fears of AGW is that conditions will change rapidly in a way that will result in net negative changes to conditions that impact the lives of humans.

    R Schmidt-
    I believe your comment speaks for itself. You are unable to discuss the actual science and hold to your beliefs in spite of the accurate science. You believe it is appropriate to call other names and wish them harm when they do not share your belief system. A shameful behavior IMO.

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  14. 14. phalaris 1:08 pm 03/7/2013


    It would also be good to know how close practical, large-scale systems can come to the theoretical minimum with current technology.
    My guess is they’d require substantially more than 5% of the plant output.

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  15. 15. RSchmidt 1:28 pm 03/7/2013

    @Sisko, “You are unable to discuss the actual science…” LOL, ROFL, that is so funny coming from you. Hilarious. The science has been present to you over and over for years! Yet you ignore it and lie about it. There is no logic, no evidence that can break through your thick skull because you have no interesting in knowing the truth. All you want to do is continue the denier FUD tactic. You never present any evidence to support your own conclusions you just make claims that there is no evidence that contradicts your beliefs. Well there is tonnes of evidence, much of it here, much of it presented to you directly. The fact that you have refused to read it or even acknowledge it, is a reflection on you. The problem isn’t the science. It is you. So when you accuse me of attacking you instead of arguing science it is the most hypocritical thing you can say. Why don’t YOU argue the science, in the mean time I am going to direct the blame where it belongs, on ignorant and corrupt individuals such as yourself who keep sadistically flogging a dead horse because it profits them to do so.

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  16. 16. G. Karst 1:30 pm 03/7/2013

    I heard this story elsewhere, but it seems to fit this thread:

    “Once upon a time there was a little bird, who was happy and contented. But a little over ambitious.

    He flew higher and higher trilling his happy song, until the earth fell away and he realized he was cold and hungry.

    He was freezing with the altitude and consequently… He fell.

    Into a warm moist cow pat where he indeed thawed, but could not escape.

    “Help me!” he cried. “Help me: I am a victim of misfortune!”

    A cat heard his trilling, and said “what is the matter?” .

    “I am up to my neck in bullsh*t” said the bird, “And I need help to get out!”

    “Nothing easier ” said the cat tugged him out and ate him.

    The morals of this story are as follows:

    1/. If you overreach your ability, you are likely to end up with your wings frozen and in the sh*t.

    2/. If you are warm and comfortable stuck in the sh*t, mostly its better to keep your mouth shut.

    3/. Not everybody who says they can help you out, is your friend.

    And that is the problem. Mankind is in the sh*t, and no one really denies that. The problem is working out who in fact is your friend, and who just wants to eat you.” GK

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  17. 17. syzygyygyzys 1:40 pm 03/7/2013

    Mr. Simon,

    Does your estimate of the increased cost of electricity (if current technology were used to separate CO2) include both operating and capital cost? If it does include both costs, could you share what they might be for a typical coal-fired power plant? DOE database from 2005 says the average size is about 667 megawatts.

    Does the cost above include the operating and capital cost for transport to and geologic storage of the CO2? If so, please share those estimates. I’ve been curious to know how that would work as a practical matter.
    • Do most existing plants have geologic structures for CO2 storage within reasonable proximity?
    • What sort of geologic structures are suitable?
    • Is the capacity for storage sufficient to handle the power plant CO2 output?

    It looks like you have put a lot of thought and work into this post. Any of the above info you could share would be appreciated.

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  18. 18. syzygyygyzys 1:45 pm 03/7/2013

    G. Karst,

    Good story. Thanks.

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  19. 19. lamorpa 2:09 pm 03/7/2013


    You asked, “point out anything that I have written above that is not accurate”.

    Your comments attempt to ignore, as I stated, “simple scientific realities and worldwide trends that unequivocally demonstrate the reality of human activity induced climate change.” Nonsensical assertions that, because there is not exact agreement on the mechanisms, rates, or fluctuations in near-term direction, the phenomenon somehow doesn’t exist is a dodge.

    Either you are playing a contrarian game to the wrong audience (only simpletons would be fooled) or you have problems with following logical arguments. What else can be said?

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  20. 20. G. Karst 2:30 pm 03/7/2013

    “simple scientific realities and worldwide trends that unequivocally demonstrate the reality of human activity induced climate change.”

    How many times must it be repeated – Just because you say something, with great conviction, hardly establishes it’s validity. It hardly matters, how many people can repeat that conviction by rote. What does matter is the continuous increase in CO2 and statistically flat-lined GMT. The hypothesis (model) does not allow for such long periods of non-response. GK

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  21. 21. Sisko 2:38 pm 03/7/2013


    I have not written that humans do not impact the climate. Read what I have written again.

    I wrote that we do not yet know with a reasonably tight margin of error what the actual rate of warming will be and I have written that we do not know the net positive and negative impacts and I have written that almost all mitigation activities are a poor use of limited resources.

    Both statements are accurate. You know that the climate changes regardless of CO2 and it is foolish to claim that all changes are due to the CO2 humans have released.

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  22. 22. OgreMk5 2:49 pm 03/7/2013


    Just out of curiosity, can you point me to some peer-reviewed work that describes possible benefits of global warming?

    And if you say anything about plant growth, I will know that you don’t have a clue about the subject.

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  23. 23. lamorpa 3:21 pm 03/7/2013


    The assumption that CO2 is the significant and major cause, and the idea that it will cause a warming effect is very strongly supported. Reductions in output are a pretty good idea. They’re not talking about dumping iron oxide in polar waters, or any other radical ideas here. If you want to view your ideas and the general consensus here as varying degrees of extremism on the subject scale, literal interpretation of your assertions is the one that is ‘way out there’. If you are trying to be shocking to get people to think more about their assumptions, well, you may be having a ‘warming’ effect. CO2 sequestration falls within my bounds, but I’ll agree with you that climate tinkering does not.

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  24. 24. G. Karst 3:38 pm 03/7/2013

    This fellow:

    ‘S. Fred Singer is Research Fellow at The Independent Institute, President of the Science and Environmental Policy Project, and a Distinguished Research Fellow, Institute for Space Science and Technology. He was the first director of the U.S. Weather Satellite Service. He is the former director of the Center for Atmospheric and Space Physics, and former Chief Scientist, U.S. Department of Transportation.’

    Wrote a book which deals with GW benefits:

    Hot Talk, Cold Science – Global Warming’s Unfinished Debate

    By S. Fred Singer
    Foreword by Frederick Seitz

    “it sounds strange to hear about benefits from a global warming. Nevertheless, the scientific literature supports the view that increases in CO2 concentration and global temperatures, were they to materialize, might actually improve human well-being. Some benefits include a CO2-enriched biosphere more conducive to plant growth, longer frost-free growing seasons, greater water efficiency for plants, and more available farmland at higher latitudes.

    A reduction in severe storms would be another likely benefit if global warming were to occur. Since a global warming would probably mostly warm the latitudes farther north and south, the temperature gradient between the equator and the poles would fall, thereby reducing the severity of storms. (Contrary to anecdotal reports, theory and observations indicate that severe storms, both tropical and extratropical, have not increased in the past 50 years. In fact, North Atlantic hurricanes have noticeably declined in frequency and in intensity.)”

    There are many other benefits (ie reduced heating fuel), but I’m sure you are able to come up with a few yourself. Peer reviewed or not. GK

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  25. 25. Sisko 3:55 pm 03/7/2013


    I would guess that you are not really interested in what the benefits could result from a warmer world you completed discount the idea that farm production may increase in many places around the world as a result.

    There are many papers written on the topic- try googling if you are really interested

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  26. 26. RSchmidt 4:19 pm 03/7/2013

    @Sisko, it is very simple; as the planet warms the oceans rise. Approx 23% of the world’s population live in coastal zones. These Cities, Towns, Villages will be flooded. So unless you can provide a good argument as to why events like Katrina and Sandy are a good thing, the debate is over. And that doesn’t even touch on the negative affects on crops, ecosystems and disease control. Once again, this has been provided to you before in detail, so your claiming that you are not aware of the negative effects is a lie. Regardless of what you claim we do have a high degree of certainty about the harmful effects of climate change because we are already experiencing them.

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  27. 27. Sisko 4:30 pm 03/7/2013


    Once again you do not seem to be reading what I have written very closely.

    I have not disagreed with the concept of AGW

    I have written that the rate of warming associated with additional CO2 seems to actually be much lower than many have claimed it would when justifing the implementation of immediate mitigation activities. A slower rate of warming equals much less potential harms.

    I have written that building and maintaining a robust infrastructure is the bast defense against harms from adverse weather or a changing climate. Some nations do this well and other barely do it at all. It is the responsibility of individual nations to make this a priority.

    I have written that most proposed climate mitigation actions are a very poor use of limited resources. Given the worldwide CO2 growth curve and the fact that 3 billion more humans will be gaining access to electricity and personal transportation and thereby emitting more CO2, it is inevitable that CO2 concentrations will continue to rise for at least several decades. Implementing highly expensive actions in the USA that may result in CO2 being at 450 ppm in 40 years vs 452 ppm is a waste of resources.

    What specifically do you disagree with?

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  28. 28. Sisko 4:41 pm 03/7/2013


    But the oceans are NOT rising at an alarming rate. They have been rising at at a very consistant rate since we have had reliable data to make measurements and it will equate to about a foot per century. The fact that the rate has not shown an increase has been quite a disappointment to those who were sure that AGW would lead to an increase in the rate. It needs to increase by 600% to be consistant with some of Hansens predictions.

    When I review the long term data on sea level (and I agree there are differences of opinion on long term sea level) but the Hallam curve is a generally accepted source. It shows that sea level is near to historic lows, so it should be expected to rise over time regardless of more CO2.

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  29. 29. RSchmidt 4:44 pm 03/7/2013

    @Sisko, “What specifically do you disagree with?”

    “I have written that the rate of warming associated with additional CO2 seems to actually be much lower than many have claimed” untrue, it is faster, especially in the most vulnerable regions such as the poles and middle east.

    “I have written that building and maintaining a robust infrastructure is the bast defense against harms from adverse weather or a changing climate.” how does a robust infrastructure fix cities below sea level?

    “I have written that most proposed climate mitigation actions are a very poor use of limited resources.” says a denier who thinks doing anything to address AGW is a waste of resources.

    This is just the FUD tactic; Fear, Uncertainty and Doubt. That is what you do. You troll sites with news about AGW and you claim that “there is no scientific evidence that…”, “we aren’t certain about…”, “this is all too expensive…”. You don’t back any of it up but that’s not your tactic. You don’t want to provide evidence or information, you just want everyone to doubt the science. Because doubt is enough to cause inaction. Again, the problem here is you and your deliberate attempt to cloud the issue for your own personal gain. Is this really the best thing you can do with your life?

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  30. 30. G. Karst 5:29 pm 03/7/2013

    Sisko wrote:

    “I have written that building and maintaining a robust infrastructure is the bast defense against harms from adverse weather or a changing climate.”

    I think, you need to add a few more items, to the things that a robust infrastructure protects us from:

    Terrorist attacks
    Intact transport system
    Treasure (wealth)

    It is a win-win option, no matter what the universe throws at us. It requires much treasure which requires a well oiled financial system and thriving economy. Hmmm GK

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  31. 31. Sisko 7:50 pm 03/7/2013


    You are such a zealot as to be laughable. What has the rate of waming been over the last say 17 years? Isn’t it statistically zero? Yes

    Do you not know that the local land height in relation to sea level is impacted far more by the changes in the land than by changes in sea level? Places all over the world build sea walls to protect themselves from this.

    Most climate mitigation are very inefficient. Please try to outline a specific climate mitigation action that you believe is cost effective. Tell us how much the action would cost, how much it would reduce CO2 emissions and how much that will impact the weather/climate. If you can not do that how can you state the action is effective.

    Link to this
  32. 32. David_Lewis 9:23 pm 03/7/2013

    American Electric Power CEO Mike Morris says his company was going to build at scale using a process they had tested at pilot scale that would add 2 cents kwhr to the 5 cent kwhr cost of generating electricity from coal, except the regulator would not allow the company to recover one dime of the cost because politicians have not put in a price on carbon in the US. AEP gave up a DOE grant. See: Living on Earth, Death of Carbon Capture.

    Adding 40% to the wholesale cost of electricity does not add anything like 40% to the final retail cost. The cost of the transmission and distribution stays the same.

    Link to this
  33. 33. dwbd 11:11 pm 03/7/2013

    A whole lot cheaper to just forgo the Coal & go Nuclear. As-a-matter-of-fact new Reactors can simply replace the Coal boiler in the existing plant at a trivial cost of $1k per kwe, FAR, FAR CHEAPER than adding Carbon Capture.

    Carbon capture or CCS runs around $200-$400/tonne of CO2 captured, Nuclear replaces Coal at a cost of < $22 per tonne of CO2 avoided. Factory produced Nuclear could easily be cheaper than Coal thus the cost of CO2 avoidance would be negative, every ton of CO2 avoided would put money in the bank. NO OTHER TECH that is scalable can achieve that.

    Link to this
  34. 34. phalaris 1:13 am 03/8/2013

    There is also the question of what they do with the captured carbon dioxide. As I remember the state of the sequestration debate a couple of years ago, there was no clear answer to this.

    Link to this
  35. 35. RSchmidt 8:05 am 03/8/2013

    @Sisko, “You are such a zealot as to be laughable.” Since you are the one who is evangelizing an ideology based on nothing more than politics that would make you the Zealot.

    “Please try to outline a specific climate mitigation action that you believe is cost effective.” nice try at a deflection but it was you who wrote, “that most proposed climate mitigation actions are a very poor use of limited resources” so you must have done the calculations to prove that, “If you can not do that how can you state the action is (in)effective?”

    Once again a typical comment from a shill. You make whatever inane comments you like then claim it is everyone else’s responsibility to prove you wrong. You seem to believe that there is no burden of proof on you.

    Of course this is pointless. This has been going on for years. There is nothing that will convince you because you have no interest in knowing the truth. You are just a corporate shill paid to spread disinformation. You have nothing to contribute to this issue.

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  36. 36. G. Karst 10:14 am 03/8/2013

    RSchmidt declares in exasperation:

    “Of course this is pointless. This has been going on for years.”

    Maybe NOT. NASA has been very reluctant to publish the results of it’s NVAP project.

    The NASA water vapor project (NVAP) uses multiple satellite sensors to create a standard climate dataset to measure long-term variability of global water vapor.

    NASA recently released the Heritage NVAP data which gives water vapor measurement from 1988 to 2001 on a 1 degree by 1 degree grid, in three vertical layers.1 The NVAP-M project, which is not yet available, extends the analysis to 2009 and gives five vertical layers.

    Apparently, it shows a decrease in the pertinent water vapor, during a period of warming. Without an increase in the total water vapor, the whole CAGW paradigm collapses.

    Interesting times – to be sure. GK

    Link to this
  37. 37. Sisko 10:15 am 03/8/2013

    An example of a climate mitigation action that was proposed that does not seem to make sense from a cost effectiveness perspective.

    James E. Hansen called for the shutting down of all coal-fired power plants in the USA by 2030, in order to avoid the global warming caused by the emitted CO2.

    What effect would this specific actionable step actually have on global warming?

    The paper tells us that 1,994 billion kWh/year were generated from coal in 2009 and that the average CO2 emission is 1,000 tons CO2 per GWh generated.

    So by 2030 Hansen’s plan would reduce CO2 emissions by roughly 2 GtCO2 per year.

    Roughly half of this “stays” in the atmosphere (with the rest disappearing into the ocean, the biosphere or outer space) so the annual reduction after 2030 will be around 1 GtCO2/year and over the period from today to year 2100 the cumulative reduction would be 80.5 GtCO2.

    The mass of the atmosphere is 5,140,000 Gt.

    So the net reduction in atmospheric CO2 would be around 16 ppm(mass) or 10 ppmv.

    If we assume (as IPCC does) that by year 2100 the atmospheric CO2 level (without Hansen’s plan) will be around 600 ppmv (“scenario B1”), this means that with Hansen’s plan it will be 590 ppmv.

    Today we have roughly 390 ppmv.

    Using IPCC’s 2xCO2 climate sensitivity of 3.2C we have:
    Case 1 – no Hansen plan
    600 ppmv CO2
    ln(600/390) = 0.431
    ln(2) = 0.693
    dT (warming from today to 2100) = 3.2 * 0.431 / 0.693 = 1.99

    Case 2 – Hansen plan implemented
    590 ppmv CO2
    ln(590/390) = 0.414
    ln(2) = 0.693
    dT (warming from today to 2100) = 3.2 * 0.414 / 0.693 = 1.91C

    So Hansen’s plan will result in a total reduction of global temperature by year 2100 of 0.08C.

    But what will this non-measurable reduction of global temperature cost?

    The total, all-in capital cost investment to replace 1,994 billion kWh/year capacity with the least expensive alternate (current nuclear fission technology) is between $4,000 and $8,000 per installed kW (say $6,000 on average). [Note: If we replace it with wind or solar, it will cost several times this amount per generated kWh, due in part to the low on-line factor.]
    1,994 billion kWh/year at a 90% on-line factor represents an installed capacity of:
    1994 / 8760 * .9 = 0.251 billion kWh

    This equals an investment cost of 0.251 * 6,000 = $1.5 trillion

    Does spending $1.5 Trillion to avoid a temperature rise of .08C seem a cost effective use of limited resources?

    Link to this
  38. 38. lamorpa 12:07 pm 03/8/2013


    You point, as you’ve evolved it, is well made. As a nation, directing most resources to reduction of our CO2 emissions results in a ‘drop in the bucket’ world reduction, while neglecting sea level rise preparedness, is not a good strategy. I think people have a problem with the root attitude of simply saying it is not important (even if that is effectively true). Translation: I think you’ll ‘sell’ your ideas better if you lead with the idea that, since sea level rise is inevitable because of the overall world problem, that it should be addressed with equal importance as other plans.

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  39. 39. G. Karst 11:24 am 03/9/2013

    I have only heard of one solution to our current problems, that makes sense, but turns our current thinking upside down.

    It is probably the most important findings, since the great stades, began melting.

    Be sure to watch this video by Dr. Allan Savory in Los Angeles this past week.

    Warning – this will severely damage many paradigms of land use and what actually causes climate damage. Enjoy. GK

    Link to this
  40. 40. syzygyygyzys 3:54 am 03/10/2013

    Compelling video. It makes sense to me. The presentation makes a strong case for learning what the actual mechanisms are before you go shoot the elephants. It seems there could be a maxim lurking about here somewhere.

    I have searched for anything about stades melting. The only “stade” I’ve found is a unit of measure. What am I missing?

    Link to this
  41. 41. G. Karst 12:11 pm 03/10/2013

    @ syzygyygyzys:

    Sorry, I hadn’t realized the word had become so obscure. Scientists refer to ice stades in a few different ways. Some refer to the splitting of an ice mass into different stades. Some refer to it as the “period” of glaciation, as in interstadial periods.

    All it really means is a large area of growing ice sheet. Maybe someone more familiar with the scientific definitions will be able to point you towards a technical definition. I too, was unable to find an adequate definition. Yet the word is commonly used in ice sheet and glacial studies. Strange…GK

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  42. 42. dwbd 12:20 pm 03/10/2013

    @Sisko, you are forgetting that a lot of those Coal power plants are old and must be replaced anyway and cost of replacement is about $4-5k per kw, certainly no cheaper than Nuclear built at that scale. Add to that, a lot of the older plants are being required to upgrade their emissions controls for mercury, SOx, NOx, lead etc, so you will have to add those costs to existing Coal power plants.

    And O&M/fuel costs of built Nuclear plants are lower than Coal, even at the current low price on Coal, and that WILL increase substantially as the higher grade, cheaper Coal resources are exhausted, and the higher value export market develops. And lifespan of the new GenIII Nuclear power plants is about double of the new Coal power plants.

    And then there are the added health, land, infrastructure costs of maintaining the Coal power plants. And that is ignoring CO2. And that is a bogus assumption, you may not believe in it, but like it or not, Repub or Dem, State & Federal and International agreements are going to be forcing Carbon Costs upon us, one way or another. And then there are major cost savings by going Nuclear instead of the Solar & Wind pixie power fantasies.

    And then there are SMR’s that can just replace the Coal Boiler with a buried Nuclear Steam Generator. China started constructing their first commercial 200MWe high-temp Gas-Cooled Pebble-Bed Modular reactor Dec 2012, scheduled for completion by end of 2017. At a cost for the First Unit of total $2,380 per kwe. So just for the Nuclear Reactor & Steam Generator could easily be $1,000 per kwe. That would be a whole lot cheaper than continuing to burn Coal. More like several $trillion in savings by 2030. See:

    We could always order the reactors from China or Russia, just like we buy almost all our Solar panels from China, since the US Gov’t is embarked on a De-industrialization program. Can’t allow indigenous Nuclear Tech to be developed by the nation that invented Nuclear Energy.

    So within that 20-30yr time-frame it would SAVE $trillions by switching to Nuclear.

    Link to this
  43. 43. syzygyygyzys 2:33 am 03/13/2013

    I found this when searching for “stades”

    It refers to stades as ice-sheet maxima and interstades as ice-sheet minima.

    If you search for “ice-sheet stades”, you get lots of hits. For example:



    Link to this

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