Negative CO2 Emissions

byclip_image002 Kevin Kilty

An article in the January 2020 Issue of Physics Today (1) presents an interesting and very readable overview of methods to capture and store away CO2 emissions. The purpose of this guest blog is to summarize a few key points the paper makes, and add some commentary. WUWT has covered some of this same territory recently here and here.

Motivation

Of course, the motivation for negative emissions technologies (NETs), or CO2 capture, is to bring atmospheric CO2 back to safe levels. Although the article fails to mention what safe means in this context, and what levels are unsafe, it alludes to melting polar ice and methane escaping from melting permafrost as consequences of unsafe climate. Nothing unusual here. Despite relegating its case for an unsafe future to such enterprises as the IPCC, the article does provide some insight into the cause of what seems to be the current “crisis” mentality. It is 1.5°C temperature rise goal of the 2015 Paris agreement. As readers of WUWT already know, this is not a 1.5°C increase from now, but rather from an estimated pre-industrial level — meaning that two-thirds of that margin is already gone and we have but 0.5°C left to work with. I suspect most people do not understand this subtle point.

Eventually the article makes a brief excursion into more phenomena by which climate change would become unsafe — forest fires, droughts, and sea level rise. All of this is also familiar to WUWT readers.


Technologies Involved

The best part of the article is its summary of technologies, the NETs, that might be able to remove 10 to 20Gt of CO2 annually from the air above and beyond the approximately one-half of our 37Gt (Gt = 1012 kg)annual emissions which will eventually be captured by nature anyway.

Biological solutions (BECCS)

These include policies to prevent deforestation combined with technical efforts at reforestation, afforestation (establishing forests in regions not previously forested), and better agricultural practices. While estimates are that perhaps 3.5Gt of CO2 could be captured annually with these methods, Stanford’s Rob Jackson and Columbia University’s Julio Friedmann point out the lack of details about land and ecosystems disturbances, water usage, land-owner incentives and needed resources such as energy and nutrients. Once possible negative side effect of forestation the article fails to mention is the potential albedo feedback of darkening a billion hectares of Earth’s surface.

Carbon Capture and Storage (CCS)

Although not discussed specifically in the article, CCS is established in a few instances, and the captured CO2 used to enhance fossil fuels recovery. David Middleton has written here and here about the technology.

Direct Air Capture (DAC)

These are essentially chemical engineering systems which draw atmospheric air into some sort of solid resin or liquid solution which captures CO2 in controlled conditions (low temperature or low humidity) and then releases it under altered conditions. Anyone familiar with an ammonia absorption refrigerator would recognize the scheme. Once captured the system stores CO2 into porous geological reservoirs; or stores it in mineralization such as specialty concrete or in situ subsurface minerals such as olivine.

Jennifer Wilcox of Worcester Polytechnic Institute makes an interesting observation that most of the people promoting DAC are physicists. This reminds me of the energy crisis of the 1970s where physicists promoted, aggressively, a number of advanced energy conversion technologies like MHD, fusion, solar arrays in orbit; which not only couldn’t be made economical, but in some instances couldn’t be made to work.(2)


Incentivizing action

Putting aside the question of the very need for all these activities, the weakest part of the discussion is its failure to specify any realistic means to overcome the principle obstacles: sources of energy, cost, financing of R&D, and paying O&M costs.

The ubiquitous benchmark for all these technologies appears at present to be able to capture and store for about $100 per tonne of CO2 (1000 kg tonnes). Yet, even $300 per tonne might seem cheap the article suggests if the worst of climate change become reality. A cost of $100 per tonne of CO2 captured implies a “cost” of burning a gallon of gasoline as about $1.30.(3)

All of the proposed technologies require energy input. If this energy comes from fossil fuels, it simply leads to more CO2 to capture and costs climb commensurately — to estimates of $1000 per tonne in some instances. Financing the required R&D appear just a matter of enacting a few billion to a few tens of billions of dollars of Federal support, and the O&M costs might be covered by partnerships with industry who have need of the CO2, like the petroleum industry, or covered by the taxpayer in subsidies and production credits, or a carbon tax. The proponents are optimistic. As the article quotes one…

“We know the recipe; we’ve done it over and over again. We have sustained, long-lived R&D programs that drop the price enough that we start making policy. And then we expand policies to align with markets. That is exactly what we did for solar, wind, and nuclear, and batteries.”

The recipe does seem familiar, but not necessarily successful. We have no economical grid scale batteries. Wind and solar have small market penetration so far except in special circumstances. And there is at least a suspicion that rather than align with markets, too much wind and solar undermines markets.

Despite its shortcomings the article is well assembled and informative.


Notes:
  • (1) David Kramer, Negative Carbon Dioxide emissions, Physics Today, Vol. 73, No. 1, p.44-51 , January 2020.
  • (2) Much of the current climate crisis resembles the energy crisis of the 1970s, especially in the variety of complex solutions being offered, and in a hurry up and do something mania. In the 1970s much of the hurry up policies made problems worse and eventually had to be undone.
  • (3) Holman Jenkins in the January 21, 2020 issue of the WSJ wrote that “A carbon tax equivalent to 13 cents per gallon of gasoline would have let Republicans in 2017 realize their fondest tax-reform hopes….” But the costs being considered here show a disparity that green groups would decry. A 13 cents per gallon tax would only be an appetizer.

130 thoughts on “Negative CO2 Emissions

  1. Plants in Greenhouse like CO2 levels of 1000 ppm and above. Excessive CO2 levels in greenhouses of 5,000 ppm can cause dizziness or lack of co-ordination to humans. Higher than recommended levels can also cause necrosis of plant leaves. Present atmospheric CO2 levels are far below what plants would like and even further below dangerous levels for animals.
    The effect of CO2 of World temperature and climate is speculative and all the so-called Climate models that attempt to predict the CO2 effects are all defective to various degrees that would under normal circumstances render them defunct. The CO2 meme, however, has become attached to various political, social and quasi-religious beliefs that render it beyond proper scientific investigation in the more committed minds.
    The idea of interfering with the Earth’s atmosphere (CCS) which has functioned perfectly well for millions or billions of years is lunacy of the first order.

    • To your last point nicholas, we have lunatics advocating giving over the act of interfering with the climate to Government and anybody paying attention knows how tragic that can be. Some idiot in the Press will give it a catchy tag name like the “War on Global Warming” or Rising Sea Levels, maybe even life affirming CO2.
      Here in the U.S. we have placed Bureaucratic Officers in charge of waging protracted “wars” on things. War on drugs, War on poverty, War on illiteracy, the list is long and missions abject failures.
      It should be painfully obvious by now that allowing our government to declare war on anything short of enemy ships off our shores will have devastating consequences, most of them unintended but nonetheless devastating.

      • “….War on drugs, War on poverty, War on illiteracy, the list is long and missions abject failures….”

        On the contrary. These missions have been immense successes. They have created bureaucratic armies and funnelled huge amounts of money towards vested interests. They have provided employment for millions who could not have been employed in any other meaningful way.

        Northcote Parkinson refers….

        https://en.wikipedia.org/wiki/Parkinson%27s_law

        • Homelessness was ended 10 years ago in Denver. At least that was the plan. Now the homelessness problem is worse than ever, but there are a dozen city departments that are working hard on it.

          • Scissor
            The solution to the problem is to only hire the homeless to staff the city departments working on the problem. It would be called a “Homeless Hiring Preference.”

        • Back many years ago I went to elementary school in a small town in North Carolina. At the time there were 27 teachers, 1 principal, 2 secretaries, 1 nurse, 2 cleaning ladies and a part time maintenance man.. That’s effectively a 4 to 1 ratio of teachers to ancillary personnel. I’d hate to even try to guess that ratio now. I know the local school where I now live has more ancillary personnel that teachers.

          • A full one-third of the staff will be “paras”, and what they do exactly I do not know, but I have checked out a few schools and the staff to student ratios are 1:6 or below.

      • Yes, 40,000 ppm is the figure I’m more familiar with. Tissue culture of many cells is routinely conducted in an atmosphere controlled at this concentration (4% CO2).

    • “Excessive CO2 levels in greenhouses of 5,000 ppm can cause dizziness or lack of co-ordination to humans.”

      Office buildings often operate at 5000–6000 ppm CO2. Submarines are generally held at 8000 ppm, and concerts can get up to 15,000 ppm. Your breath is 20,000 ppm. Your numbers are off. Life evolved in much higher CO2 concentrations then 5000 ppm for almost 50 million years in the Cambrian.

      • IIRC Humans start having issues with CO2 levels around 4% by volume and it is lethal at around 7.5% by volume. That would be between 40,000 and 75,000 ppm. (Per my graduate Environmental Toxicology course).

        • My question is this:
          Is it the amount of CO2 in itself that is the danger or is it the effect of preventing sufficient oxygen absorption that is the danger?

      • From NASA for the Apollo spacecraft “Because carbon dioxide has a powerful stimulatory effect on respiration as well as a marked influence on acid-base balance, the problems of carbon dioxide removal and the ability of man to perform adequately when exposed to various concentrations of carbon dioxide have become important. Synergistic interactions were considered independently in establishing acceptable levels of carbon dioxide for the Apollo Program. The optimal mission design level was established as 505.4 N/m2 (3.8 torr) (0.004 atmospheres) carbon dioxide partial pressure, with a maximum limit for continuous exposure of 1010.8 N/m2 (7.6 torr) (0.01 atmospheres) . The emergency limit was set at 1995 N/m2 (15.0 torr) (0.02 Atmospheres) carbon dioxide partial pressure.”

    • Agreed plus:
      **The ubiquitous benchmark for all these technologies appears at present to be able to capture and store for about $100 per tonne of CO2 (1000 kg tonnes). Yet, even $300 per tonne might seem cheap the article suggests if the worst of climate change become reality. A cost of $100 per tonne of CO2 captured implies a “cost” of burning a gallon of gasoline as about $1.30.(3)**
      300 per tonne cheap? Only if we get ridiculous and listen to the fear mongers. The problem today is that the media and public are REPEATING the misinformation while only a handful are actually doing research. There is NO NEED to capture CO2. How about feeding the poor instead?

      • Exactly. There is no need. Removing it will also have no effect on climate – and they will take it too far – just wait and see.

  2. What is a safe CO2 level? Remember we are due to slide into the next glacial phase of the Ice Age we live in, and CO2 levels in the glacial phase drop to dangerously low levels. I would say something around 1,000 ppm would be a safe level. Now some fools in a hurry want to reduce CO2 levels from the current 400 ppm level? How about if they figure how to do this only locally, like say New York, Los Angeles, and Chicago in the USA? Or only in Africa, for example? Or only for the northern hemisphere? Otherwise I would be forced to defend our brothers and sisters, the CO2-breathing plants, whom I love dearly, especially in a great tossed salad with honey mustard dressing.

    • We know that C3 plants are seriously stressed below 180-200 ppmv. We have a pretty good idea that CO2 hasn’t been above 1,000 ppmv since the Oligocene. 400-600 ppmv is probably not a problem.

  3. If higher concentrations of atmospheric CO2 are ‘unsafe’, then Earth has been ‘unsafe’ for 99% of it’s existence.

    This is madness!

    • Since humans have only been around for less than 0.1% of the earth’s existence then it’s quite possibly true that the earth has been unsafe for 99% of the time – for humans.

      • Homo Sapiens have been around for a relatively short time, but the life forms we evolved from have enjoyed a much higher concentration of atmospheric CO2 than we do. Without higher levels of CO2 in the past, we would not be here today. If CO2 levels are allowed to drop in the future, we could go extinct in the next glacial period, along with most of the life on Earth.

        Sequestering CO2 is like spraying water on the Titanic!

    • Yeah? You want to live with dinos in your back yard? Excess CO2 causes dinosaurs, that is really unsafe !

      • CO2 averages 800 ppm in homes!
        Are you claiming to own domesticated dinosaurs??
        Do you have a license for that???

  4. And there am I, trying to increase my carbon footprint and my CO2 emissions to help green the planet and keep it nice and cosy.

  5. In a closed bedroom, the morning CO2 level can easily reach 2000 ppm.

    Even more if you have been active.

    Love mentioning that fact to CO2-haters. 😉

  6. “That is exactly what we did for solar, wind, and nuclear, and batteries.”
    Umm…sorry – no you / we / us….DIDN’T.

    Think again – from scratch – and get back to us.

    • We have sustained, long-lived R&D programs that drop the price enough that we start making policy

      Wind:
      When I worked with wind turbines in mid 80’s in Denmark, there was no government intervention I am aware of. We sold a lot 75kW ones to the US, not because the electricity would be cheaper than from conventional generators, but because of tax benefits. This fact caused a manufacturing issue, as the US customers only wanted the turbines December.
      Anyway, wind turbines started out like any other product in this world and had nothing to do with government energy policy as such – that all came later on.
      The wind turbines today are an improvement on the price per kW, but have little chance of significant improvement in the future. Wind turbines need to be at least hundred times more effective, before they can can compete wit fossil fuel plants in terms of intrusiveness.
      So no, “we” didn’t start anything, it was mainly started by a company which used to manufacture galvanized manure tanks, and got convinced by Henrik S. to expand the slowing business by making wind turbines.

      Batteries:
      How far have they come since 100 years ago, and how far can they go?
      On the island I lived on from time to time, we has kerosene fueled generators charging Ni-Fe battery banks, a battery type developed by Edison. The Ni-Fe batteries degraded extremely slowly and demanded little maintenance, apart from topping up with distilled water. In fact, some Australians use Ni-Fe batteries these days.
      If we compare these the Ni-Fe batteries to the Li-Ion batteries, more commonly used today, there are some improvement, but also some environmental drawbacks. However, Li-Ion is not thousand times better than Ni-Fe, and until now there is nothing to suggest an improvement on such scale is possible. Batteries on any large scale is currently economically, ecologically and practically insane. Take the newest non-nuclear sub marines, they a driven by fuel cell technology, giving the benefit of the relative high energy from the fuel, no oxygen consuming diesels and half the submarine filled with batteries. By the way, these submarines are more silent than the nuclear submarines.
      “We” didn’t start R&D on the batteries, Edison did so without “we” intervention.

      Nuclear:
      Yes there has been a lot of government investment in these. Among many reasons, R&D on nuclear is very costly. It makes sense to assist the development of nuclear as the potential for improvement is significant and the intrusion factor is already low and does not need the external infra structure for coal or gas transport.
      So nuclear is probably the only concept where “we” did help R&D.

      CO₂ capture:
      Why would “we” help R&D in removing CO₂ to slow the greening of the planet?
      Even if it may become economical viable, it likely to do more bad than good.

  7. “…policies to prevent deforestation combined with technical efforts at reforestation, afforestation (establishing forests in regions not previously forested), and better agricultural practices…Once possible negative side effect of forestation the article fails to mention is the potential albedo feedback of darkening a billion hectares of Earth’s surface.”

    Wouldn’t increasing forestation etc also cause an increase in the release of water vapour, thus increasing cloud cover and compensating for the darkening effect?

    • Well, the climate is complicated, isn’t it? Why wouldn’t the increased humidity act as a greenhouse gas, and warm the planet for this reason?

      • On the other hand, increasing evaporation cools the environment. More water in the air generally leads to more clouds and more rain, both of which lead to cooling.
        So which predominates, warming or cooling?
        Anyone who says they know is either lying or delusional.

    • Enhanced photosynthesis uses more energy to convert CO2 and water to sugar.

      The energy used isn’t available to heat the environment.

  8. bring CO2 back to safe levels. what? you want to kill us all to reduce CO2 from 0.04% of atmosphere to WHAT?

    • I’m right here. I love CO2. We turn the CO2 in combusted fossil fuel exhaust into good paying full time jobs and money. We want the full flow exhaust stream and not a slide slip like the Petra Nova or Boundary Dam projects.
      https://youtu.be/RQRQ7S92_lo We first take it out of the atmosphere and then later out of the combusted exhaust. We also want the heat energy out of the exhaust. http://www.SidelSystems.com Where possible we would like to construct large ranges of commercial greenhouses and use the captured heat from the exhaust to heat and or cool these greenhouses in which food crops can be grown. More jobs created.
      The cooled CO2 can be used for enrichment purposes in these greenhouse growing areas or diverted to our CCU System and transformed into other useful-valuable products.
      Waste is not waste if it has a purpose.

  9. 7.81 Gigtonnes CO2 is 1 ppm, and we send out 36 Gigatonnes per year = 4,6 ppm. 2,6 ppm is taken up by nature (12 Gt in plants and 8 Gt in the oceans), 2 ppm = 16 Gigatonnes CO2 is left in the atmospere. – So if we want 410 ppm to be the level, we should take out 16 Gigatonnes a year and store it. Nature takes the rest. Where to store it? Possibly in the oceans where it would have ended anyway. That will give only a little acidification as the oceans already store 132.000 Gigatonnes of CO2 and has the function as a pH 8 buffer solution as lime stone is dissolved in it. – That was the technical part. – Is it a good idea? I am not afraid of CO2 and it will be very expensive.

    • You use a decimal point interchangeably in the European and U.S. style. The 132.000 Gt you mention would in U.S. mode become 132,000, but your point is correct that it could be buried in the ocean, reacted with olivine in the oceanic crust, without harm — but at what cost and who bears it? And why?

    • “7.81 Gigtonnes CO2 is 1 ppm, and we send out 36 Gigatonnes per year = 4,6 ppm. 2,6 ppm is taken up by nature (12 Gt in plants and 8 Gt in the oceans), 2 ppm = 16 Gigatonnes CO2 is left in the atmosphere.”

      Sorry, but this pseudo-fact can be repeated another 100,000 times, and it will still be bullshit.

      The FACT is that we have <b<no measurements of ALL of the various atmospheric “sources” and “sinks” of CO2, which means we don’t know how much any change in atmospheric CO2 is caused by human emissions. Absent any such measurements, the null hypothesis should simply be that our estimated contribution to the total estimated emissions is equal to our estimated contribution to the total increase in CO2 levels. In other words, on the order of a few percentage points.

      • “Sorry, but this pseudo-fact can be repeated another 100,000 times, and it will still be bullshit.

        The FACT is that we have <b<no measurements of ALL of the various atmospheric “sources” and “sinks” of CO2, which means we don’t know how much any change in atmospheric CO2 is caused by human emissions. "

        Spot on.

      • What Bjarne Bisballe was trying to say is that if all the human emissions of CO2 remained in the atmosphere, the CO2 concentration in the atmosphere would increase by 1 ppm per 7.81 Gigatonnes emitted, if there were no other sources and no sinks. It basically comes from a mass balance on the atmosphere. I’ve done similar calculations and obtained 7.78 Gigatonnes per ppm, so Bjarne Bisballe’s value is reasonable.

        He also recognizes that a NET 2.6 ppm/yr, or about 20 Gt/yr, is absorbed by nature. This can also be obtained by a mass balance on the atmosphere. If current human emissions are 36 Gt/yr, this would result in a 4.6 ppm per year increase if all the human-emitted CO2 remained in the atmosphere, but if actual CO2 concentrations are increasing at only 2.0 ppm/yr, then a NET 2.6 ppm per year, or 20 Gt/yr, are removed by nature.

        This does not mean that all the natural sources and sinks have been taken into account. The oceans emit CO2 to the atmosphere as they warm in spring and summer, and re-absorb CO2 as they cool in autumn and winter. Cellular respiration by all animals also emits CO2, and conversion of carbonic acid to calcium carbonate by shellfish removes CO2 from the oceans.

        Measurements of CO2 content at Mauna Loa show that the CO2 concentration decreases in (Northern Hemisphere) spring and summer, and increases in autumn and winter. Most of the world’s land area is in the Northern Hemisphere, and land plants consume CO2 by photosynthesis in spring and summer, but in temperate latitudes most of these plants are dormant in autumn and winter.

        The NET removal by nature represents the difference between total CO2 emissions by natural sources and total CO2 absorption by natural sinks.

        Hundreds of experiments have shown that higher CO2 levels in the atmosphere tend to speed up plant growth. If CO2 levels increase in the future, the rate of removal by photosynthesis will also increase, and will eventually catch up to the rate of human emissions of CO2, reaching an equilibrium at a higher concentration than today’s level.

      • Actually at least a dozen reputable organisations show where all the near-surface Carbon exists. The IPCC & NASA try to ignore the limestone, why?
        I find it astounding that so many people worry about the CO2 in the air without realizing that the sea has absorbed the CO2 for 500 million years and put over 99% of the carbon into limestone where it is mostly unavailable to plants forever. Here is where the gigatonnes of Carbon (not CO2) exists.
        limestone&sediments 75,000,000
        ocean deep 38,720
        methane clathrates 11,000
        coal, oil 1,220
        atmosphere 750
        soil 1,230
        Plants 550
        ocean surface 40

        There is no point is discussing sequestration if we don’t consider where the carbon now is and measure it. This is more important than most other climate research.

        • Thank you jayman!
          Oysters at 43% carbonate can single-handedly solve the problem.
          Good nourishment and the shells make good road bed and gravel pathways en route to limestone for cement factories.
          Cheers

    • My elaborated calculation is this (Gigatonnes CO2 per year). From the oceans comes 330, from land 440 and from fossils 36 to the atmosphere. Opposite direction: Oceans 338, land 452 and 16 stays in the atmosphere.
      My ppm calculation: The mass of one millionth part of the atmosphere is 5.15 Gigatonnes with a molcule weight of 29 (average). CO2 has 44 so 44/29 x 5.15 is 7.81 Gigatonne for a ppm of CO2 in the atmosphere.

  10. Nice summary Kevin Kilty. I went and read the article. You rightly state, “Putting aside the question of the very need for all these activities …” How about this re-framing of the problem statement? If the problem is warming, why not deliver the heat back to space with a solar-powered solution using the entire surface of the planet? We could flood the surface of the earth with a natural refrigerant with IR-absorbing and emitting properties to evaporate into the atmosphere. We could use buoyancy to enable convective action, even to the point that concentrated bursts of upward condensation would reach very high altitudes. We could even add electrical discharge and acoustic annunciation to show off the power of this self-governing system of heat management. And furthermore, how about some non-condensing helper molecules like carbon dioxide and methane to incrementally boost the radiative coupling at the surface to make the heat engine even more effective at absorbing energy at the hot side of the cycle, and more effective at emitting it to space at the cold side? So let’s see what happens with the climate, because this system is already out there, and the real atmosphere is readily observed by all to do exactly this. Watch the weather, especially thunderstorms. Sure, there is the static greenhouse effect slightly modified by CO2, but convective weather is the real show. It may take a few more years or decades, but eventually the engineers might be willing to explain how the heat engine concept was obvious all along.

    • Indeed, the active gasses in the IR spectrum coupled with convection act as a very efficient AC of the atmosphere : they emit into space some 170 W/m² while they absorb from the surface 17 W/m² (according to the Earth energy budget – NASA 2009). Actually a very efficient AC.

      Those who want to capture the CO2 – and all the alarmists – act as if they measured the temperature of a working AC compressor in a room, they observed that indeed the compressor is warm and conclude that this compressor must be stopped in order to cool the room.

      Brilliant move.

  11. Minor quibble: capturing CO2 from air is usually based on contacting air with either a selective (absorbing) resin, or more commonly, a water solution with affinity for CO2 (eg polyamines or just a high pH solution). I don’t think anyone expects to use low temperatures to remove CO2 from air.

    • Once the resin or solution captures CO2 it has to be made to release it in some way, or otherwise it cannot work in a cycle. As I said, look at how an absorption refrigeration cycle operates and you will see the gist of the method.

      • Of course you need some kind of regeneration cycle; worse, you need a permanent home for the recovered CO2, and these homes all appear hugely expensive. I was just noting that the post suggests low temperature can be used when absorbing CO2; as far as I know, in proposed processes the air is always at ambient temperature…. otherwise you would have a process with large energy use.

        Another quibble: It is true plants and the oceans currently take up a bit more than half of emissions. However, if you collected enough CO2 via direct air capture to “hold atmospheric concentration constant” you would start to see some fall-off in uptake by the ocean (how much fall-off and over how long is not clear), and in the longer term, a very slow drop off in net plant uptake as forests gradually move to a new (higher) equilibrium biomass… with higher CO2 release from breakdown of plant matter. So the rate of active collection of CO2 would gradually have to rise to hold atmospheric CO2 constant unless fossil fuel use was reduced.

    • It’s slow this morning, so I will make one other comment in reply. I am not arguing with your quibble, the article does mention using a variation in humidity to cycle resins. Apparently they adsorb CO2 preferentially in dry air, but prefer to replace the CO2 with water vapor in moist air. But one has to cycle the absorber through a cycle that is easy to organize — RH, temperature, and pressure all come to mind.

      Temperature variation is an attractive way to cycle the absorbers if possible because all one needs is a source of heat — solar would work for instance. As an example, CO2 is more soluble in cold water than it is in hotter water, and so one could capture CO2 by cycling water between two temperatures. I don’t know that it would be an effective method, but a person could get it to work. Absorption refrigerators use ammonia and some aqueous solution, but they have a very low COP, and this is likely to be true of any of these absorption schemes. Any scheme that would have a low COP as a refrigerator, would be expensive to run in a DAC scheme.

      Another possibility is to use two levels of pressure, but that involves work, and why use work, the highest value energy, to run a process that doesn’t have a critical schedule, and is low value work?

    • “polyamines or just a high pH solution”
      I think in terms of geochemistry, dealing with CO2 should be seen as an acid-base problem. We are creating a whole lot of acid, through oxidation, and we need to neutralise it. But to create synthetic base would require industry on the scale of that oxidation process, and would anyway produce by-product acid.

      There is a natural cycle which Arrhenius wrote about. Lava emits CO2, leaving basic rocks behind. Eventually CO2 reunites with those basic rocks. We need to accelerate that process. KK wrote about injecting CO@ into an olivine environment. Another possibility is to bring olivine to the surface, crushed and exposed. I think that is the most promising.

      • Amine solutions in water (particularly diethanolamine or methyl diethanolamine) are commonly used in the refining industry to remove acid gases from gas streams. The primary target is hydrogen sulfide (H2S), but amine solutions also absorb CO2, while allowing hydrogen, methane, and nitrogen to pass through unaffected.

        The problem of excessive consumption of amine solutions is usually solved by regeneration. A gas containing H2S and/or CO2 is contacted with cold “lean” (pure) amine solution in an absorption tower, and gas leaving the top of the tower is H2S-free, while the “rich” amine leaving the bottom of the absorption tower is chemically bonded with H2S and CO2.

        Rich amine is then heated and sent to a low-pressure “regeneration” tower, which breaks the bonds between amine and the acid gases, and the concentrated acid gases leave the top of the regeneration tower, and “lean” amine leaves the bottom of the regeneration tower, and is cooled and pumped to the absorption tower.

        In this way, the amine solution can be re-used many times before it needs to be “purged” for buildup of impurities, and the acid gases are concentrated. Sour gas containing, for example, 1% H2S can be cleaned down to 10 ppm or less, but the acid gas leaving the regeneration tower can be over 80% H2S. This concentrated H2S stream can then be further treated to generate sulfuric acid or solid elemental sulfur.

        Amine absorption and regeneration is very effective at removing toxic H2S from fuel gas, and concentrating it for further treatment, but the same process becomes prohibitive for CO2, because of the huge flow rates of CO2 in flue gas. When the amine solution is regenerated, a large stream of low-pressure, concentrated CO2 needs to be compressed to supercritical pressure (1,070 psi or more) for sequestration, which consumes about 25% to 30% of the power generated by a power plant.

        • Way back when, I worked on ways to mitigate the formation of heat-stable salts resulting from CO2 reacting with amines making carbamates. Separately, DGA destroyed most elastomers and coatings on downstream membranes.

      • I did not know that Arrhenius wrote about basic versus acidic rocks, but in geology we usually classify rocks in this manner on the basis of their silica content. So it sounds like there are two uses of these words, possibly confusing. Maybe David Middleton or someone would weigh in on any relationship between the two uses.

        • Worlds in the Making (1908) p 55:

          “It may possibly be a matter of surprise that the percentage of carbon dioxide in the atmosphere should not constantly be increased, since volcanism is always pouring out more carbon dioxide into our atmosphere. There is, however, one factor which always tends to reduce the carbon dioxide of the air, and that is the weathering of minerals. The rocks which were first formed by the congelation of the volcanic masses (the so-called magma) consist of compounds of silicic acid with alumina, lime, magnesia, some iron and sodium. These rocks were gradually decomposed by the carbonic acid contained in the air and in the water, and it was especially the lime,the magnesia, and the alkalies, arid, in some measure also the iron, which formed soluble carbonates. These carbonates were carried by the rivers down into the seas. There lime and magnesia were secreted by the. animals and by the algae, and their carbonic acid became stored up in the sedimentary strata.”

          • Well that is certainly interesting, but somewhat archaic. It is pre-plate tectonics, and at the time no one recognized that volatiles like CO2 and H2O, which come along with all magmas and especially in magma of an “acidic” (in the sense of having a high fraction of silica) rock like rhyolite, are recycled at subduction zones back into the mantle.

            The part about the soluble carbonates being carried by rivers to the sea is also noteworthy. One would think with this alkalinity being carried into the ocean constantly that the pH of the oceans would rise constantly so the stability of ocean pH was a bit of a mystery for a long time. I may be out of date, but think that the explanation that folks settled on is the neutralization of the alkalinity occurs as a result of reactions between seawater and oceanic crust — those vents at mid-ocean ridges release a lot of hydrogen ion.

          • “One would think with this alkalinity…”
            By “soluble carbonates”I think he meant bicarbonates, which would, if anything, lower the pH of the sea.

          • By “bicarbonate” I assume calcium bicarbonate, as that will likely be the dominant bicarbonate species from weathering. Now admittedly I learned this a long time ago, but I recall reading an article by Ferrin McIntyre wherein he said that carbonate and bicarbonate carried to the oceans would raise ocean pH from its present value if there were no compensating mechanisms — seafloor weathering of sediments and ocean crust. Seawater is not freshwater, I realize, but in freshwater a saturated solution of calcium bicarbonate has a pH of nearly 10.

          • Seawater is a carb/bicarb buffered solution. It is about 90% bicarb, 10 % carbonate. Bicarb is the acid side of that buffer. If you add bicarb, it lowers the pH (but not much).

  12. In his excellent speech at Davos, President Trump mentioned planting a bunch of trees. That’s the only part of the speech that got any applause probably because the audience interpreted it as a CO2 reduction policy.

    Trump trumpeted that America is getting a lot better and showed how other countries could follow suit. No applause. Oh yeah, and we’re planting a few trees. Applause.

    The elites at Davos clearly don’t care about America’s forgotten people and minorities, or their own either. Pigs!

  13. “Putting aside the question of the very need for all these activities …”
    Classic Keynesian economics – dig a hole in the ground then fill it in?
    People who advocate this carbon capture technology do not “get the joke”. Carbon Cap and Trade does not capture any CO2 – the only thing that is captured is dollars!

  14. I consider any efforts such as these to be obsolete and ignorant with respect to future energy sources.
    Anyone payig attention knows that molten salt nuclear reactors avoid all of the disadvantages of nuclear power, existing or spurious : cost – molten salt reactors can be bulit at half the cost of conventional nuclear reactors and produce power very cheaply – 4 cents per kWhr; reactors are small, can be produced in factories very rapidly and sited virtually anywhere and have no need for bodies of water for cooling’are very proliferation resistant, cannot meltdown or spew radioactive material into the environment because of low internal pressures. The technology will be commercializable within 10 years. As for sutomotive emissions, electric cars will replace gas powered vehicles over the next 20 years.

    • The technology will be commercializable within 10 years.

      ColM,
      That’s great news. Will you get back to us then, but not before. Thanks.

    • The technology will be commercializable within 10 years. 

      But fusion is only 20 years away. It has been for the last 50 years, so it must be true.

  15. “…methods to capture and store away CO2 emissions…”

    Geoengineering and sequestering CO2 are schemes that are entirely without merit.

      • There is no science behind anthropogenic warming whether it is perceived as dangerous warming or lukewarming, my little stalker.

        Show me one paper that provides evidence that atmospheric CO2 contributes to an increase in global surface temperature. I’ll save you the trouble … there isn’t one. Shock! Horror!

        Too many CO2 appeasers on WUWT. It plays straight into the hands of alarmists.

  16. Someone please let me know if these dingbats ever figure out that they can’t (can NOT) control what this planet does? Thanks!

  17. Let’s just capture carbon to plastics. Not all of it is biodegradable.

    I would also put a label “made of CO2” to cow milk.

    • I would also put a label “made of CO2” to cow milk.

      And on pretty much all if products. Everything we eat was CO2 just a few weeks before. I’d be hard pushed to name any that were not, although in the case of meat it may be a few months.

  18. Till now I have been convinced a carbon tax is a very poor idea. Now I have changed my mind. I propose a resolution at the UN in favor of a substantial carbon tax to be imposed at a national level on any country that removes CO2 from the air artificially by the use of technology. The funds collected from those greedy nations which steal this life giving, food supporting nutrient from our shared atmosphere will then be disbursed to nations that are struggling to feed their populations under conditions of underdevelopment and poverty.

  19. 10,000 ppm is 1%
    The normal human exhaled CO2 concentration is around 5%.
    If we breathe more deeply, we lower our CO2 levels in the blood, roughly in proportion to the amount of increase in in lung ventilation – the amount of air we breathe in and out in a minute.
    An increase in ventilation of around 20% is sufficient to ensure absolutely normal blood chemistry in the face of an inspired 10,000ppm load.
    There is no possible human safety issue at 1000 or even 2000ppm.

  20. An article in the January 2020 Issue of Physics Today (1) presents an interesting and very readable overview of methods to capture and store away CO2 emissions.

    Full stop there. Useless. Why not harvest our food crops and then immediately bury them…..

    • Well, there are those who would; or at least they would propose growing crops, burning to a char, and burying that. Burying the crop itself would just leave open the possibility of methane rising to the surface again. You can imagine the variety of schemes being proposed. This is why I say this climate crisis looks so much like the energy crisis of the 1970s — its that seventies show once again.

    • “grid scale” it said.

      That battery could power SA for 3 minutes, if it was even possible to draw that much power that quickly, which it is not.

      Perhaps it can power a local town for a few hours. That’s not ‘grid scale’.

    • Nick-

      For a really intelligent guy, you seem to delight in throwing in remarks that you know are not exactly on topic. The batteries made money by being a frequency stabilizer, not by supplying sustained power to the grid. Here is the quote from the article you referenced:

      “The overwhelming majority of revenue in September came from providing frequency control ancillary services (FCAS). Contingency services, which correct major frequency deviations in the grid, accounted for the highest share of revenue (55%).”

      • “not by supplying sustained power to the grid”
        They make money from both. Wikipedia says they are expected to make $18M per year from acting as reserve (buying low and selling high). On that basis, they can supply 30MW for 3 hours. Not bad returns from a device that cost about $90M.

    • Stokes, I was a PE in a major electric utility. I know grids. There’s no such thing as a grid scale battery yet. Doubt there ever will be. Stick to what you know.

    • Nick Stokes January 24, 2020 at 11:58 am

      “We have no economical grid scale batteries. “
      Yes, we do. Several. The best known is the Tesla battery in Hornsdale, SA. And it is very profitable.
      ____________________________________

      The best known is the Tesla battery in Hornsdale, SA. And it is very profitable. –> The best known is the Tesla battery in Hornsdale, SA. And it is the base of a heavily taxpayer subsidised ponzi-scheme.

  21. Carbon Capture and Storage (CCS)
    Although not discussed specifically in the article, CCS is established in a few instances, and the captured CO2 used to enhance fossil fuels recovery. David Middleton has written here and here about the technology.

    It’s important to differentiate CCS from CCUS (carbon capture, utilization and storage).

    CCS only has economic value if government imposes penalties for emissions and/or incentives for sequestration. Its value is entirely dependent on whether or not there are benefits to reducing CO2 emissions. This is entirely opinion-driven.

    CCUS has economic value irrespective of whether or not there are benefits to reducing CO2 emissions.

    • David, agree — you previously convinced me that CC utilization can be useful in appropriate situations. I suppose once underground, it’s stored, but in that case storage would be incidental to the original purpose.

    • “CCS only has economic value if government imposes penalties for emissions and/or incentives for sequestration.”

      Which isn’t reasonable economic thinking, or acting but brute political motivated force.

  22. Disappointed articles and papers discussing ‘carbon capture’ are being presented on this platform as worthy of serious discussion, in light of everything we know, and don’t know about Earth’s climate, as has been pointed out already by many of the commentors here. Why would we want to capture atmospheric C02 when it is at a historic low, not much above plant death, in the recent past. Is it because some ‘skeptics’ believe we, as in humanity, must be doing something bad by putting some C02 back in the atmosphere where it has depleted almost to nothing relative to levels throughout plant evolution? According to estimates, roughly 97% of the CO2 released into the atmosphere is natural, and about 3% is from burning fossil fuels. What is the error in that estimate? +/- 3%? When we can measure that more accurately, our own addition from fossil fuels will be immeasurable and insignificant, relative to the Planet’s oceans contribution.

  23. Carbon (dioxide) Capture and Sequestration is a very expensive way of removing CO2 from the atmosphere.

    The main problem is that the critical temperature of CO2 is about 31 C, or 88 F, meaning that it cannot be liquefied above this temperature. If the goal is to store it underground, the place where it is stored cannot exceed this temperature, at the risk of a violent expansion, explosion, or man-made earthquake if this temperature is exceeded.

    To avoid this problem, CO2 must be compressed to above its critical pressure, or 73.82 bar = 1,070 psi. Carbon dioxide emissions from power plants (normally mixed with nitrogen and water vapor) are normally at low pressure (slightly above atmospheric), so that even if the CO2 is separated from the nitrogen and water vapor, compression to above 1,070 psi (a compression ratio of over 70) requires several stages of compression and an energy input of 25 to 30% of the electric power output of the power plant.

    If this is done, the power plant puts out only 70 to 75% of the energy it could produce per tonne fuel consumed, meaning that such a plant would consume 33% to 43% more fuel per MWh net power generated (not consumed by the compressors), basically consuming valuable fuel resources much faster than necessary.

    Since the benefit of removing CO2 from the atmosphere is difficult to quantify, most power plants that have considered Carbon Capture and Sequestration have abandoned these efforts as prohibitively expensive for little (if any) return.

    • And now add all the other significant irreversibilities involved in capturing something that is only 0.04% of atmosphere per volume, and doing all of this, plus, as Nick Stokes mention, mining and crushing olivine to react it with CO2.

      It is all interesting to contemplate, but does not sound promising to me.

        • “The olivine process does not require capture.”

          I’m really curious about this possibility. Can you expand on it?

          I’ve often thought that the amine towers used for stripping natural gas of CO2 were something worth considering, but I’m not familiar with the olivine process. (I did download the Arrhenius paper you linked, but haven’t read it yet).

        • But then it would require an enormous surface area to have it run at a reasonable rate, because what this becomes is simply what geologists would call “weathering”. The article spoke mainly of bringing the “CO2 bearing liquid” (don’t know if they mean supercritical or a saturated aqueous solution, into contact with olivine rock at depth (i.e. under pressure to perhaps keep the CO2 super critical or keep the aqueous solution saturated. The article also mentioned quartz as a “carbonate” so has some chemical/geological misstatements.

  24. Articles like this acquiesce to the absurd and simply false notion that CO2 is harmful. Why does WUWT just retweet this corrosive blather, endlessly, article after article?

    Be careful what you swallow, it can harm you.

    CO2 is with O2 the foundation of life on earth. Adding it to the air is good. All the palaeo evidence shows that.

    The pseudoscience komissars pushing the CO2 lie down society’s throat, rely on the fact that, although palaeo data of atmosphere and climate over deep time refutes the CAGW notion with ridiculous totality, they can rely on the fact that, deep down in an instinctive level, they can rely on the fact that a high enough percentage of people are utterly indifferent about science and unwilling to think seriously about the vast age of the earth, preferring – perhaps unconsciously, to believe in an earth created recently, just a few thousand years ago. Even when such people have never been in a church or synagogue all their lives, they are psychologically unable to embrace deep time.

    In a young world just a few thousand years old, a catastrophe story is plausible – not much has really happened yet. But once you appreciate the vast age of the earth, and have the courage and honesty to get your head around deep time, then the remarkable stability, durability and staying power of the environment and biosphere become obvious to you. And it becomes obvious that the catastrophe stories are nonsensical and impossible.

    • I have generally found it worthwhile to listen to people on the other side, in fact every side, of this debate. I certainly don’t think these schemes are necessary, and the proposals are not very convincing. Certainly the thread didn’t suggest anyone here is “swallowing” anything, did it?

  25. All very puzzling to me. I thought the goal was to keep the planet from warming.
    The planet seems to be managing that on its own and will almost certainly start to cool eventually.
    I see no evidence that reducing atmospheric CO2 will lower temperatures and only dubious evidence that it might significantly contribute to warming. The only observable evidence would be in correlations between CO2 levels and temperatures. That seems to be only incidental.
    As well, there is really no evidence of a downside to warming. The science of attribution seems to be alchemy in action without believable results. On the other hand, the downside to cooling is obvious and can be severe.
    Tell me again why we should be concerned with CO2. Should we not be observing the climate for another century or two before taking action that could have serious unintended consequences.
    Adaptation to a warmer planet would seem to be relatively easy while cooling is much more difficult to deal with.
    Perhaps no one has noticed that all the hottest areas of the planet are heavily populated as long as water is adequate. The coldest areas are practically barren of all living things whether plant, animal, or human.
    Some of this might be explained by the fact that only a very small proportion of the planets population has any experience with the more extreme cold portions of our wold
    I live where it is relatively cool and I know a few degrees of warming would make life a whole lot more comfortable.
    I know this is preaching to the converted by posting it here but I just had to say it again.

  26. If, and that’s a big if, CO2 has such a climate impact, I would worry about all these efforts to reduce emissions and lower CO2. What happens if it gets down to 150 ppm?

  27. There are molecular sieve materials which are very effective at capturing CO2. The industrial gas companies have been using them for decades on the front end of large cryogenic air separation units to take out CO2 – and water vapour – which would otherwise freeze in the process. It is not retained, just returned to the atmosphere when the mol sieve is regenerated.
    Scale would be an issue. A big ASU produces about 5,000 tons per day of oxygen which means it processes roughly 25,000 tons of air per day. So there would only be about 10 tons per day of CO2 available for capture.
    However the technology could be applied to any large air handling system, if someone wanted to waste money that way.

  28. “This reminds me of the energy crisis of the 1970s where physicists promoted, aggressively, a number of advanced energy conversion technologies like MHD, fusion, solar arrays in orbit; which not only couldn’t be made economical, but in some instances couldn’t be made to work.(2)”.

    Seams the greatest danger to a reasonable go-ahead are selfishness, vanity and showmanship / grandstanding of:

    the small guild of the physicists.

    Tell them to get grown.

  29. “This reminds me of the energy crisis of the 1970s where physicists promoted, aggressively, a number of advanced energy conversion technologies like MHD, fusion, solar arrays in orbit; which not only couldn’t be made economical, but in some instances couldn’t be made to work.(2)”.

    Seams the greatest danger to a reasonable go-ahead are selfishness, vanity and showmanship / grandstanding of:

    the small guild of the physicists.

    Tell them to get grown.

    https://www.google.com/search?q=professor+unrat+film&oq=professor+unrat+&aqs=chrome.

  30. Amos, “Meanwhile in Scotland we’ve chopped down over 13 million of them to make way for wind turbines.”

    Enhancing by greening them wind turbines poles, e.g. with ivy. The new ivy leagues.

    Double green. Green as can green.
    ____________________________________

    Forgot to mention – one day without expensive maintainance – scrubbing, brushing and new saltwater resistant painting and that damned scrap greens by itself.

    Rusty iron, overgrown with algae and dripping moss.

    A danger to the christian seafaring.

Comments are closed.