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Is the ocean carbon sink sinking?

Filed under: — david @ 1 November 2007 - (Español)

The past few weeks and years have seen a bushel of papers finding that the natural world, in particular perhaps the ocean, is getting fed up with absorbing our CO2. There are uncertainties and caveats associated with each study, but taken as a whole, they provide convincing evidence that the hypothesized carbon cycle positive feedback has begun.

Of the new carbon released to the atmosphere from fossil fuel combustion and deforestation, some remains in the atmosphere, while some is taken up into the land biosphere (in places other than those which are being cut) and into the ocean. The natural uptake has been taking up more than half of the carbon emission. If changing climate were to cause the natural world to slow down its carbon uptake, or even begin to release carbon, that would exacerbate the climate forcing from fossil fuels: a positive feedback.

The ocean has a tendency to take up more carbon as the CO2 concentration in the air rises, because of Henry’s Law, which states that in equilibrium, more in the air means more dissolved in the water. Stratification of the waters in the ocean, due to warming at the surface for example, tends to oppose CO2 invasion, by slowing the rate of replenishing surface waters by deep waters which haven’t taken up fossil fuel CO2 yet.

The Southern Ocean is an important avenue of carbon invasion into the ocean, because the deep ocean outcrops here. Le Quere et al. [2007] diagnosed the uptake of CO2 into the Southern Ocean using atmospheric CO2 concentration data from a dozen or so sites in the Southern hemisphere. They find that the Southern Ocean has begun to release carbon since about 1990, in contrast to the model predictions that Southern Ocean carbon uptake should be increasing because of the Henry’s Law thing. We have to keep in mind that it is a tricky business to invert the atmospheric CO2 concentration to get sources and sinks. The history of this type of study tells us to wait for independent replication before taking this result to the bank.

Le Quere et al propose that the sluggish Southern Ocean CO2 uptake could be due to a windier Southern Ocean. Here the literature gets complicated. The deep ocean contains high concentrations of CO2, the product of organic carbon degradation (think exhaling fish). The effect of the winds is to open a ventilation channel between the atmosphere and the deep ocean. Stratification, especially some decades from now, would tend to shut down this ventilation channel. The ventilation channel could let the deep ocean carbon out, or it could let atmospheric carbon in, especially in a few decades as the CO2 concentration gets ever higher (Henry’s Law again). I guess it’s fair to say that models are not decisive in their assessment about which of these two factors should be dominating at present. The atmospheric inversion method, once it passes the test of independent replication, would trump model predictions of what ought to be happening, in my book.

A decrease in ocean uptake is more clearly documented in the North Atlantic by Schuster and Watson [2007]. They show surface ocean CO2 measurements from ships of opportunity from the period 1994-1995, and from 2002-2005. Their surface ocean chemistry data is expressed in terms of partial pressure of CO2 that would be in equilibrium with the water. If the pCO2 of the air is higher than the calculated pCO2 of the water for example, then CO2 will be dissolving into the water.

The pCO2 of the air rose by about 15 microatmospheres in that decade. The strongest Henry’s Law scenario would be for the ocean pCO2 to remain constant through that time, so that the air/sea difference would increase by the 15 microatmospheres of the atmospheric rise. Instead what happened is that the pCO2 of the water rose twice as fast as the atmosphere did, by about 30 microatmospheres. The air-sea difference in pCO2 collapsed to zero in the high latitudes, meaning no CO2 uptake at all in a place where the CO2 uptake might be expected to be strongest.

One factor that might be changing the pressure of CO2 coming from the sea surface might be the warming surface waters, because CO2 becomes less soluble as the temperature rises. But that ain’t it, as it turns out. The surface ocean is warming in their data, except for the two most tropical regions, but the amount of warming can only explain a small fraction of the CO2 pressure change. The culprit is not in hand exactly, but is described as some change in ocean circulation, caused maybe by stratification or by the North Atlantic Oscillation, bringing a different crop of water to the surface. At any event, the decrease in ocean uptake in the North Atlantic is convincing. It’s real, all right.

Canadell et al [2007] claim to see the recent sluggishness of natural CO2 uptake in the rate of atmospheric CO2 rise relative to the total rate of CO2 release (from fossil fuels plus land use changes). They construct records of the atmospheric fraction of the total carbon release, and find that it has increased from 0.4 back in about 1960, to 0.45 today. Carbon cycle models (13 of them, from the SRES A2 scenario) also predict that the atmospheric fraction should increase, but not yet. For the time period from 1960 to 2000, the models predict that we would find the opposite of what is observed: a slight decrease in the atmospheric fraction, driven by increasing carbon uptake into the natural world. Positive feedbacks in the real-world carbon cycle seem to be kicking in faster than anticipated, Canadell et al conclude.

There is no real new information in the Canadell et al [2007] analysis on whether the sinking sink is in the ocean or on land. They use an ocean model to do this bookkeeping, but we have just seen how hard it is to model or even understand some of the observed changes in ocean uptake. In addition to the changing ocean sink, drought and heat wave conditions may change the uptake of carbon on land. The infamously hot summer of 2003 in Europe for example cut the rate of photosynthesis by 50%, dumping as much carbon into the air as had been taken up by that same area for the four previous years [Ciais et al., 2005].

The warming at the end of the last ice age was prompted by changes in Earth’s orbit around the sun, but it was greatly amplified by the rising CO2 concentration in the atmosphere. The orbits pushed on ice sheets, which pushed on climate. The climate changes triggered a strong positive carbon cycle feedback which is, yes, still poorly understood.

Now industrial activity is pushing on atmospheric CO2 directly. The question is when and how strongly the carbon cycle will push back.
 
—–

Canadell, J.G., C.L. Quere, M.R. Raupach, C.B. Field, E.T. Buitehuis, P. Ciais, T.J. Conway, N.P. Gillett, R.A. Houghton, and G. Marland, Contributions to accelerating atmospheric CO2 growth from economic activity, carbon intensity, and efficiency of natural sinks, Proc. Natl. Acad. Sci. USA, doi 10.1073, 2007.

Ciais, P., M. Reichstein, N. Viovy, A. Granier, J. Ogee, V. Allard, M. Aubinet, N. Buchmann, C. Bernhofer, A. Carrara, F. Chevallier, N. De Noblet, A.D. Friend, P. Friedlingstein, T. Grunwald, B. Heinesch, P. Keronen, A. Knohl, G. Krinner, D. Loustau, G. Manca, G. Matteucci, F. Miglietta, J.M. Ourcival, D. Papale, K. Pilegaard, S. Rambal, G. Seufert, J.F. Soussana, M.J. Sanz, E.D. Schulze, T. Vesala, and R. Valentini, Europe-wide reduction in primary productivity caused by the heat and drought in 2003, Nature, 437 (7058), 529-533, 2005.

Le Quere, C., C. Rodenbeck, E.T. Buitenhuis, T.J. Conway, R. Langenfelds, A. Gomez, C. Labuschagne, M. Ramonet, T. Nakazawa, N. Metzl, N. Gillett, and M. Heimann, Saturation of the Southern Ocean CO2 sink due to recent climate change, Science, 316 (5832), 1735-1738, 2007.

Schuster, U., and A.J. Watson, A variable and decreasing sink for atmospheric CO2 in the North Atlantic, J. Geophysical Res., in press, 2007.


680 Responses to “Is the ocean carbon sink sinking?”

  1. 501
    SecularAnimist says:

    Rod B wrote: “Nuclear energy may not be the ultimate solution, but it doesn’t come close to the extreme negative case offered by SecularAnimist.”

    As I mentioned previously, I have never seen the case actually laid out by nuclear advocates that even a large expansion of nuclear power can make a significant reduction in carbon emissions.

    If there’s a positive case, let’s see it — and sweeping pronouncements that nuclear power is “THE answer” don’t make a case.

    How many new nuclear power plants? Built where? Built by when? How much carbon emissions will they eliminate? Will they reduce current emissions by replacing existing coal generation, or just reduce expected growth by “replacing” coal generation plants not yet built, or just maintain the status quo by replacing existing aging nuclear power plants that must be decommissioned in the next several decades? How long will any such benefits last, once the easily and inexpensively extractable uranium supplies are exhausted? (And by the way, once you start talking about “solving” the uranium depletion problem by deploying breeder reactors all over the world, you are no longer talking about a “proven” nuclear technology but one that is not up and running on a large scale anywhere, for good reason.)

    Where’s the plan? The American Solar Energy Society report I cited above offers a case for reducing US carbon emissions by 60-80 percent by 2050, through full application of existing efficiency and clean renewable energy technology. Certainly that case should be critically evaluated and not accepted at face value. But where is any such case from the nuclear industry or nuclear advocates? Where’s the plan?

    Nuclear power may offer some benefits in reducing carbon emissions — at enormous cost, after decades of building new plants, for a limited time until fuel supplies are depleted, at enormous risk from accidents & terrorism & weapons proliferation, while introducing other environmental problems from the highly toxic nuclear fuel cycle (from mining and refining, to transport, to sequestering waste). A cost benefit analysis of nuclear power with regard to carbon emissions requires a realistic assessment of nuclear power’s potential for reducing emissions, and a realistic assessment of the costs and risks — rather than pretending that all the costs and risks are “made up” by anti-nuclear zealots, pretending that the waste sequestration issue has been “solved”, that breeder reactors will “solve” the uranium depletion problem, etc.

    Matt wrote: “Of course, Patrick Moore, the co-founder of Greenpeace changed his mind about nuclear.”

    Patrick Moore is, in fact, a paid consultant to the nuclear industry. Moore was briefly associated with Greenpeace, and ever since has been a propagandist for mining, timber and other environmentally destructive industries. Like Lomborg, Moore’s lies have been well documented; unlike Lomborg, Moore’s lies can be directly traced to the environmentally destructive corporations who pay him to lie on their behalf.

  2. 502
    Jim Galasyn says:

    Matt asks for clarification: “Is your worry about killing the last one of anything, or is it about killing anything?”

    My question was about mass extinction of species and the destruction of entire ecosystems, aka “biodiversity loss”: Do you consider even the low-balled estimate of 1500X the background rate, among the highest in the planet’s history, acceptable?

    Lomborg has been very clear on his feelings: Biodiversity loss is not a catastrophe, and the environmental situation is (somehow) actually improving. I gather from your reply that you agree with this position. From speaking with Lomborg personally, it’s clear that he couldn’t care less if leopard species are hunted to extinction, as long as people are making money.

    I tried to impress on him the astounding rate of ocean biomass loss, but it didn’t bother him a bit. Great sharks are functionally extinct now, leading to the destruction of whole ecosystems and leaving watery deserts in their wake — but to Lomborg that’s really nothing to worry about. You see, I’m the “alarmist,” and he’s the “environmentalist.”

    I don’t know how your question about GM organisms is at all relevant: are you proposing we make GMO sharks that are resistant to longline hooks?

  3. 503
    AK says:

    #493

    Tim McDermott Says:
    12 November 2007 at 12:32 AM

    OK, back-of-the-envelope time for solar power satellites.

    These birds need to be in geosynchronous orbit if we want to have a steady supply of power from them.

    In a brief search of the web, the cheapest price I could find for putting mass on geosynchronous orbit was $4700/kg. The best power density of PV was more than 6 g/w. Rounding (this is boe, after all) this comes out to 6 g/w times 5 $/g = 30$/watt. Just for putting the PV material on orbit. Supporting structure, power conversion and transmission extra, orbit keeping mechanics extra. Engineering the bird and building the ground station(s) extra.

    I don’t think this economically viable. Not for a long time.

    Tim

    On the remote chance that you’re being serious, I will just point out that the plan as described both here and in my links, involves getting most of the mass from the moon, after creating an industrial base on the moon (not a “moonbase” but an entire industrial base).

    Costwise, there are several things to consider. First, economies of scale will lower the price of launch to orbit by several orders of magnitude. Second, the entire launch and setup cost doesn’t create a system of power satellites, it creates a system of factories to make power satellites, using power and mass already away from earth. Once that factory system is built, the actual mass of power satellites will be many orders of magnitude greater than what was launched into orbit.

  4. 504
    J.S. McIntyre says:

    Re 478

    Sorry I didn’t get back to you sooner; been a busy weekend.

    “I’m all in favor of developing renewable energy sources, and quickly (for a number of reasons). But I think it not helpful to present a Pollyanna case and, to pick a phrase normally tossed the other way, cherry pick the trade-offs.”

    I really don’t think anyone is offering a Pollyanish vision of what we’re facing, Rod. If anything, it strikes me that every solution being offered up re renewable, sustainable sources carries with it the understanding that there is going to be nothing that one could describe as “easy” to this. There are still bugs to be worked out, trade-offs to be understood. From a societal perspective, it will be a difficult sale, particularly to anyone who wants things to “stay as they always were”.

    “Nuclear energy may not be the ultimate solution, but it doesn’t come close to the extreme negative case offered by SecularAnimist.”

    Of course, I disagree. And as I do so, I also understand that we will likely see an upswing in nuclear power generation. But it remains trading one bad solution (fossil fuels) for another. As Smith pointed out, nuclear power generation offers a zero/infinity problem in terms of risk. On one hand you have dependable power source that is “clean” in terms of emissions. On the other hand, while the odds seem low for a mishap, such a mishap would be catastrophic.

    Consider the response to Katrina or the Southern California wildfires. Regardless of what happened, people can go back and rebuild (though in New Orleans’ case, as beautiful and historic a place as it may be, it was a mistake to go back with the idea that things will resume as normal – the geology of the place, existing as it does on a river delta, insists its days are numbered). Now consider what would happen to the same area of Southern California if there were a large nuclear accident, containment was breached, and the winds directed the fallout over, say, the L.A. basin.

    And storage IS a serious, yet-to-be adequately solved issue. Consider: they are now construction a THIRD sarcophagus for Chernobyl. Even in the case of intact reactors, their days are numbered. Sooner or later they need to be retired. So where do you put all that radioactivity? It’s an important consideration.

    “J.S. is amazingly cavalier with the benefits of renewables and the elimination of things like electric reliability and availability.”

    Again, I don’t see how I’m being “cavalier”, my mistaken comment re power consumption notwithstanding. (And I consider the characterization somewhat as odd given you had earlier told me I was being “thoughtful”. Make up your mind. *smile*). As I noted above and elsewhere, any change is going to be accompanied by the understanding that we are going to have to give things up. Sacrifice for the future, so to speak. This is not necessarily a bad thing, either.

    “Discarding the 99% availability standard (actually higher than that) out of hand sounds like the true goal is simply to get us back to nature and near pioneering days (sans all the wood burning, of course!) with a couple of bulbs and a transistor radio during the day and nada during the night — unless you’re one of the elite that can install a 30 meter propeller in the back yard to go with their 30 square meters of silicon.”

    Now that is an interesting spin. Can you tell me who wants that, specifically? (Yeah, I know, you’re being cynical.) I certainly would like to see this technological civilization move on and outside the earth’s gravity well into the greater solar system. Can’t do that with a couple of bulbs and a transistor radio.

    If anything, it may be that the only way we can attain this goal is to be a little more realistic about what our civilization is doing to the biosphere we live in, and make the changes we’ll need to in order to continue. Remember, right now this world that sustains us is the only one we have and I, for one, would like our descendents to be able to survive in it and live happy, healthy lives. Maybe that makes me odd; I sometimes think so, given how little consideration people seem to have for the future and their descendents. (An odd, ironic thing, given how much value we seem to place in the health and safety of our children when they are young.) If we continue as we are, I really don’t see our civilization’s (and in the long term, our species’) survival as a high probability outcome. And frankly, even if we engage in a high-priority effort to change the way we live my hopes for our future are bleak.

    First and foremost I’m a humanist, Rod. I am constantly amazed by what we have done as a species, the things we have built, the art and music we’ve created, the depth of thought that informs our global literature. We have a heck of a positive legacy, in spite of our faults (which are often legion). We have a capacity to excel beyond ourselves, to see ourselves and the world we live in with constantly evolving perspectives full of meaning and purpose.

    We are the only intelligent life form we know of. I’d like to think there are others, but I see no evidence of this and doubt such evidence will present itself in my lifetime. We have a capacity to excel beyond ourselves, to see ourselves and the world we live in with constantly evolving perspectives. This is such an amazing gift. I would love to see all these things that are good survive and with them intelligent, thoughtful people with the ability to understand and appreciate what they offer.

    Beyond the obvious technical and ecological/AGW issues that surround them, that’s what informs my “enthusiasm” for the potential inherent in renewable/sustainable energy solutions.

    If that seems cavalier to you, so be it.

    Have yourself a better day.

  5. 505

    To the Moderator – I would like to post the following in this section and also on the home page as a Challenge to the scientific community.

    I am an architect and would like to make some comments regarding electrical energy generation and consumption, as well as issue a challenge to the scientific community, the same challenge I recently issued in a keynote talk at Science 2007 at the University of Pittsburgh.

    First, some statistics. Seventy-six percent of all electrical energy produced in this country goes just to operate buildings. The EIA calculates 71%, but they do not include industrial building operations (HVAC), which when added, brings the total to 76%. The average residence in the US consumes approximately 45 kBtu/sf-yr of delivered energy and the average commercial building (non-government) about 85 kBtu/sf-yr.

    Between 384 kBtu/sf-yr (Seattle) and 680 kBtu/sf-yr (Las Vegas) of solar radiation is delivered free to every square foot of roof in the US. Between 364 kBtu/sf-yr (Seattle) and 539 kBtu/sf-yr (Las Vegas) of energy is delivered free to every un-shaded south wall (south facing surface) in the US. Or, to put it another way, between 748 kBtu/sf-yr and 1,219 kBtu/sf-yr of energy is delivered free to two surfaces of every building in the US. With delivered solar energy there are no losses for mining, processing, transporting, transmission, construction and operations of plants and infrastructure, water consumption, mountain top removal and reclamation, habitat loss, black lung disease, mercury contamination, radioactive material transportation, storage, security and proliferation issues, plant decommissioning, demolition and disposal, greenhouse gas emissions, pollution and associated health and other issues.

    Next, an observation. Global oil production has peaked or is about to peak. Natural gas is not far behind. After the peak, the price of these resources will continue to climb and less and less will be produced and consumed. The one fossil fuel positioned to push the planet past 450ppm CO2 in the atmosphere is coal. Coal is primarily used to produce electricity for the operation of buildings.

    Finally, the Challenge.

    If the following problem can be solved, we stand a good chance of averting the catastrophic effects of global warming and climate change:

    Opportunity: Between 748 kBtu/sf-yr and 1,219 kBtu/sf-yr of solar energy is delivered free to two surfaces of every building in the US. Average building energy consumption in the US can be reduced 30% by designing to the latest building code standards.

    Challenge: Design an elegant and simple solution (cost effective) to convert and store 32 kBtu/sf-yr (2% to 4%) of this free delivered energy for intermittent use in residences and 60 kBtu/sf-yr (5% to 8%) for intermittent use in commercial buildings.

    Approximately 72% of the converted and stored energy will be used in residences (43% in commercial buildings) for heating, cooling, ventilation and hot water, (low temperature applications – 60 degF to 120 degF) and the remainder for electricity.

    The statistics are in your favor. Over the next 30 years, three quarters of the built environment in the US will be either new or renovated. Most structures in the US are either one or two stories in height (i.e. no solar shading).

  6. 506

    I would add to the Challenge “the solution should be adaptable globally.”

  7. 507
    Matt says:

    500 Jim Eager: First, Three Gorges was not built to store energy as with a pump-storage-generation facility…

    I didn’t say anything about Three Gorges. I was referring to the Tianhuangping pumped storage facility. That might explain why your numbers are all wrong.

    And the first link in google (1) shows 16m3 of storage, and 590m heigh difference. But in fact, in checking my math, instead a of $42/kwh of storage the real cost is $84 as you need one storage reservoir above and one below to catch it (duh).

    So storing energy is even worse than I said it would be.

    1. http://www.power-technology.com/projects/tianhuangping/

  8. 508
    David B. Benson says:

    Matt (495) — For electrical power generation, any form of biomass can be used in one or another of a variety of reactors. So it is most economic to grow fast growing perennials as well as use agricultural, forestry and municiple biowastes. For example, Dayton, Ohio, uses the biogas for the anerobic digestion of sewage to power two medium-sized electric generators.

  9. 509
    Dave Rado says:

    Re. Matt, #494:

    Of course, Patrick Moore, the co-founder of Greenpeace

    He was not a co-founder of Greenpeace (although he falsely claims to be). However, he did go on the first Greenpeace voyage (see here).

    As for the reasons for his sudden “epiphany”, no-one knows the real reason for it, as he hardly speaks like a rational person about it.

    In The Great Global Warming Swindle he said: “When I left Greenpeace it was in the midst of them adopting a campaign to ban chlorine worldwide. Like I said, ‘you guys, this is one of the elements in the periodic table, you know; I mean, I’m not sure if it’s in our jurisdiction to be banning a whole element.'”

    In fact Greenpeace was not campaigning to “ban chlorine”, but to ban the use of CFCs, which in fact, despite Moore’s claim that it was impossible to do, was banned under the Montreal Protocol – and not because of Greenpeace’s campaign (it is hardly credible for a rational person to claim that governments are so easily swayed), but because of the overwhelming scientific evidence that CFCs were damaging the ozone hole, which convinced every major government in the world that this action was necessary.

    Even if it had been the use of an element, rather that of a complex compound that does not occur naturally, that was being banned, Patrick Moore’s claim would still be irrational. We have banned the use of the element lead in gasoline and in paint; and we have laws against the dumping of the element mercury into our lakes and rivers; and we have banned the use of the element radium to illuminate watch and clock hands. Moore does not campaign to have any of those bans rescinded.

    He is currently a paid lobbyist for and consultant to, not only the the nuclear energy, but also the mining, biotechnology and logging industries (and has been since the early 1990s). Moore has dismissed concerns about the impacts of logging, mining and forest clearance for agriculture on the Amazonian rainforests, which is hardly a rational position to take.

    He regularly describes all environmentalists as being “anti-human”.

    All in all he is not someone that any rational person could take seriously or have respect for, nor does he appear to have any integrity.

    Of course, this does rather beg the question of how such an person could have become a leading figure within Greenpeace for several years, and perhaps that does reflect badly on Greenpeace , but without knowing the true details of how he came to fall out with them, and what he was like before he fell out with them, it’s hard to judge.

  10. 510
    SecularAnimist says:

    J.S. McIntyre wrote: “We are the only intelligent life form we know of.”

    That’s not true. There are plenty of other intelligent life forms with whom we share the Earth — for example, non-human primates, birds and dolphins. All of them have been shown to have language, reasoning ability, and culture. At least some of them have basic mathematical skills. Non-human primates and birds make and use simple tools, and teach their young to do so. Some non-human primates and some birds have learned to communicate intelligently using human languages (sign language in the case of primates, and spoken English in the case of birds).

    Intelligence is pervasive in nature, and other “intelligent life forms” are all around us. What they lack is the particular, synergistic evolutionary developments that have enabled the human species to develop advanced technologies to exploit and manipulate our “environment” — the very technologies that now threaten our existence, as well as the existence of many of the other “life forms” on this planet.

    It would be correct to say that the human species is the only advanced technological species we know of. Whether our technological prowess will ultimately prove to be a successful evolutionary development, or one that leads to our extinction after a mere 100 to 250 thousand years of existence on this planet, remains to be seen.

  11. 511
    James says:

    Re #501: [As I mentioned previously, I have never seen the case actually laid out by nuclear advocates that even a large expansion of nuclear power can make a significant reduction in carbon emissions.]

    Certainly you have, in past threads, unless you’re insisting on detailed engineering. But at the risk of tediousness, here are the simple answers:

    [How many new nuclear power plants?] Figuring that the existing ~100 nuclear plants in the US produce 20% of the electricity, it would take about 300 to replace coal-fired generation, fewer if we also put intensive efforts into other alternative generation & energy efficiency.

    [Built where?] Wherever there’s a large coal-fired plant that needs to be replaced. That minimizes investment in new transmission lines & other infrastructure.

    [Built by when?] ASAP. Ask the French how long it takes them to construct a plant, using their standard designs.

    [How much carbon emissions will they eliminate?] However much is generated by the coal-fired plants they replace.

    [Will they reduce current emissions by replacing existing coal generation, or just reduce expected growth by “replacing” coal generation plants not yet built…]

    Depends on how many are built, of course. If I was dictator, bringing a new nuclear plant on-line would require shutting down at least half that much fossil-fuel generation.

    […replacing existing aging nuclear power plants that must be decommissioned in the next several decades?]

    Why must existing plants be decomissioned? They might need refurbishing to bring them up to current standards, but there’s a lot of structure that would be wasted by just shutting down.

    [How long will any such benefits last, once the easily and inexpensively extractable uranium supplies are exhausted?]

    Long enough to develop other technologies, with luck. Maybe in 50 years or so, we’ll be able to build fusion plants or solar power satellites – or maybe current political trends will result in a nuclear war that makes it all moot. The point is that we know that bad things will happen if the world keeps on with increasing CO2.

  12. 512
  13. 513
  14. 514
    David B. Benson says:

    James (511) — The United States current mines (and burns) about one billion tons of coal per year. Assuming that the average carbon fraction is 60%, that’s 600 million tons of carbon added yearly to the active carbon cycle.

    Not to mention the mercury, asenic, selenium, etc. emitted.

  15. 515
    J.S. McIntyre says:

    re 510

    “It would be correct to say that the human species is the only advanced technological species we know of.”

    *grin*

    I stand corrected for the imprecision of my statement, for that was the inherent meaning of what I was getting at, as the rest of what I was saying more or less implied.

    Thank you.

  16. 516
    dhogaza says:

    He’s being very mealy-mouthed with words here when he says “doomed to immediate or early extinction.” Early extinction? Either we made them extinct or we didn’t.

    Not sure why I’m bothering to answer you, since I assume your ignorance is obvious to nearly everyone here but …

    No, he’s not being mealy-mouthed. Extinction is typically a gradual event, and we don’t usually know exactly when a particular species goes extinct even for species we’ve named.

    Species have rebounded.

    Name one that was in trouble due to habitat loss that has rebounded without intense (and very costly) human intervention to restore habitat?

    Actually, just for fun, name noe that has rebounded WITH intense (and very costly) human intervention to restore habitat?

    What is his timeline for the ultimate extinction to take place?

    It will differ for every species at risk, which is why it is incredibly stupid for you to expect a precise answer in a general statement about global extinction.

  17. 517
    AK says:

    Re: 513 Jim Galasyn…

    For those preferring more formal reports: Space‐Based Solar Power As an Opportunity for Strategic Security (PDF)

    FINDING: The SBSP Study Group found that to the extent the United States decides it wishes to limit its carbon emissions, SBSP offers a potential path for long‐term carbon mitigation.

    This study does not take a position on anthropogenic climate change, which at this time still provoked significant debate among participants, but there is undeniable interest in options that limit carbon emission. Studies by Asakura et al in 2000 suggest that SBSP lifetime carbon emissions (chiefly in construction) are even more attractive than nuclear power, and that for the same amount of carbon emission, one could install 60 times the generating capacity, or alternately, one could replace existing generating capacity with 1/60th the lifetime carbon emission of a coal‐fired plant without CO2 sequestration.

    BTW, thanks for those links.

    AK

  18. 518
    Jim Eager says:

    Re 507 Matt: “I didn’t say anything about Three Gorges. I was referring to the Tianhuangping pumped storage facility. ”

    Thanks for pointing that out, Matt, but it would have been nice if you had said so clearly and provided the link in your original post.

    Are you aware that pump-storage-generation has been used since the 1890s and is already widely used in the US to even out peak load imbalance and provide greater than peak generation during peak demand?

  19. 519
    Dave Rado says:

    While on the subject of solar powered satellites, what is the potential viability or otherwise of putting a huge bank of photovoltaic solar panels in the Sahara and supplying electricity to Africa, Europe and parts of Asia from it?

  20. 520
    AK says:

    Re: 519

    Dave Rado Says:
    12 November 2007 at 4:23 PM

    While on the subject of solar powered satellites, what is the potential viability or otherwise of putting a huge bank of photovoltaic solar panels in the Sahara and supplying electricity to Africa, Europe and parts of Asia from it?

    I’ve never seen a formal analysis, but in addition to the obvious socio-political problems, just one word: sandstorms.

  21. 521
    Cat Black says:

    #418: John Coleman of The Weather Channel says AGW is a scam: “I have read dozens of scientific papers. I have talked with numerous scientists.” We keep running into this basic tenant: that climate scientists, in aggregate, are either mislead in mass or are idiots. 2,500 of them working their entire lives writing in countless scholarly works reviewed by yet more scientists and readers. All idiots. John Coleman can out-think them over his morning Post Toasties.

    Worse news, the average human can’t see past it. This is why catastrophes that surpass the human scale, and our limited ability to reason around small problems but not large ones, is our ultimate undoing.

  22. 522
    Nick Barnes says:

    Dave Rado @ 519: what is the potential viability or otherwise of putting a huge bank of photovoltaic solar panels in the Sahara and supplying electricity to Africa, Europe and parts of Asia from it?
    Considerable (although it’s unlikely to be a single huge project and more likely to be a steady development of a number of large projects, and much of it might be solar thermal rather than photoelectric). I recall reading about an Algerian project, which I think was under construction.

  23. 523
    SecularAnimist says:

    James wrote: “Ask the French how long it takes them to construct a plant, using their standard designs.”

    It’s curious how often nuclear proponents cite France as an example for the US to follow with regard to nuclear power, given that the US, not France, is the largest producer of nuclear-generated electricity in the world, and the US has 104 operating nuclear power plants compared to only 59 in France.

    According to Bloomberg.com, the Olkiluoto-3 nuclear power plant under construction in Finland — “the first nuclear plant ordered in Western Europe since the 1986 Chernobyl disaster” — has experienced serious problems including “flawed welds for the reactor’s steel liner, unusable water-coolant pipes and suspect concrete in the foundation” which have led to 25 percent (so far) cost overruns and an expected delivery delay of at least two years beyond the original schedule.

    The group constructing the reactor is led by France’s Areva SA, and the reactor is Areva’s “next generation” European Pressurized Reactor (EPR) design, which is presumably representative of the new standardized reactors that nuclear proponents would like to see built by the hundreds.

    The Bloomberg article quotes Paul Joskow, director of the Center for Energy and Environmental Policy Research at MIT: “The nuclear industry has put forward very optimistic construction cost estimates, but there is no experience that comes even close to backing them up.”

    James wrote: “Why must existing plants be decomissioned? They might need refurbishing to bring them up to current standards, but there’s a lot of structure that would be wasted by just shutting down.”

    Pushing aging nuclear power plants beyond their original service life (typically 30-60 years) invites disaster. Old nuclear power plants wear out, and are themselves a form of “radioactive waste.”

    They have to be decommissioned which costs hundreds of millions of dollars and takes decades. In the US, the Nuclear Regulatory Commission licenses nuclear power plants for 40 years, at the end of which time the operator can apply for a renewal or decommission the plant, which the NRC says will typically cost $300 million and may take 60 years.

    Yes, this is very wasteful.

  24. 524
    Jim Eager says:

    Re 507 Matt: “But in fact, in checking my math, instead a of $42/kwh of storage the real cost is $84 as you need one storage reservoir above and one below to catch it (duh).”

    Perhaps in the Chinese example, but this is definitely not true for many pump-storage-generation facilities. For example, the twin facilities down stream from Niagara Falls, one on the US side, one on the Canadian side, both draw and discharge water directly from/to the Niagara River, so both plants have only a single storage reservoir.

  25. 525
    James says:

    Re #519: […what is the potential viability or otherwise of putting a huge bank of photovoltaic solar panels in the Sahara…]

    About the same as putting them anywhere else. Figure out how much electricity you want, look up the price of that many solar panels, and multiply. Then figure in the cost of storage if you want power at night.

  26. 526
    Dave Rado says:

    Re. Nick Barnes, #522, what about the points raised by AK in #520? And if these problems are considered to be realistically surmountable, why isn’t this option being pushed hard now? I don’t think the IPCC WGIII report considered it (correct me if I’m wrong).

  27. 527
    David B. Benson says:

    Dave Rado (526) — What’s ‘being done” in the U.S. I don’t seem to be able to link it, but its in the Scitizen web site entitled

    [Opinion] Climate Change Politics

  28. 528
    Ray Ladbury says:

    A quick note on solar solutions. First in the Sahara: I’m not sure how many Harmattan seasons the cells would survive before they either blew away or their cover glasses were so pitted that their efficiency decreased to unviable levels. Maintenance of even wells in the Sahara is nontrivial. There are few empty spaces in the world, and there are usually reasons why they stay empty.

    Now in space: It costs ~$10000 to launch a Coke can into space. Moreover, any space-based system will suffer from the same problems that Satellite communications systems suffer from–Sending a microwave beam from GEO probably isn’t terribly practical, and in LEO/MEO, you need a buttload of satellites and/or they are in a nasty radiation environment that will shorten satellite lifetime. It is really hard to get a satellite to last longer than 15 years no matter what you do.

  29. 529
    Dave Rado says:

    Re. David Benson (#527), the Scitizen article is very interesting but I don’t see its relevance to my questions about solar panels in the Sahara?

  30. 530
    AK says:

    Re: #526 Dave Rado

    The Algeria Project uses mirror-concentrated sunlight. From one news story:

    The plant will be a hybrid, using both sun and natural gas to generate 150 megawatts. Of that, 25 megawatts will come from giant parabolic mirrors stretching over an area that’s roughly the equivalent of 45 football fields.

    I couldn’t find a picture of the Algerian installation (drawing rather, it’s not built yet), but here’s one of an installation in the Mojave Desert at Kramer Junction, California.

    The mirrors appear to be enclosed in a transparent (glass?) cover, and to rotate to follow the sun. Both transparent covers and moving parts are vulnerable to sandstorms, but probably less so than light-weight solar panels. Heavy moving solar panels would still have the same problems as parabolic mirrors. AFAIK, sandstorms aren’t unknown in the Mojave, but aren’t as bad or frequent as in the Sahara.

    According to the article linked/quoted above, “[t]he project is still at an early stage and faces daunting financial and technological obstacles.” Of course, space-based power will also face “daunting financial and technological obstacles.

  31. 531
    Matt says:

    Re: #528 (Ray’s comments)

    I’m with Ray on challenges of captivating solar cells and beaming energy down from space.

    Folks need to keep in mind the quantities involved to make a dent. Assume you had a 10 pound aluminum frame to hold a 1m2 of solar cells. That frame would be required to cope with wind loads of almost 1000 pounds (~100psf). Additionally, you would need >10 years of US primary aluminum output to make all the frames. (3.6T KWH demand per year, 324 kwh/yr/m2 from solar cell, ~6B pounds of aluminum per year). The numbers are absolutely staggering.

    I also don’t get space power. With >100 dB path loss, to meet US demand would require the things in space to beam down 4e18 watts 24×7. Even to meet 1% of US demand the numbers are still unbelievable.

  32. 532
    Rod B says:

    J.S., as a small example I thought the “*grin*” over the “99% availability for electricity was a bit cavalier. But maybe I inferred too much. Your post #504 is learned and not cavalier.

  33. 533
    Rod B says:

    re 519: “…what is the potential viability or otherwise of putting a huge bank of photovoltaic solar panels in the Sahara and supplying electricity to Africa, Europe and parts of Asia from it?…”

    You still have the (now MASSIVE) storage problem and would lose tremendous amount of power through transmission even with DC. But any quicky checkout of something no matter how bluesky can’t hurt.

  34. 534
    AK says:

    Re:

    528

    Ray Ladbury Says:
    12 November 2007 at 7:59 PM

    Now in space: It costs ~$10000 to launch a Coke can into space. Moreover, any space-based system will suffer from the same problems that Satellite communications systems suffer from–Sending a microwave beam from GEO probably isn’t terribly practical, and in LEO/MEO, you need a buttload of satellites and/or they are in a nasty radiation environment that will shorten satellite lifetime. It is really hard to get a satellite to last longer than 15 years no matter what you do.

    531

    Matt Says:
    12 November 2007 at 9:26 PM

    I also don’t get space power. With >100 dB path loss, to meet US demand would require the things in space to beam down 4e18 watts 24×7. Even to meet 1% of US demand the numbers are still unbelievable.

    We’re talking about power satellites (or at least the antennas) in GEO, with a phased array antenna beaming to an earth rectenna. Assuming 5.8 GHz, and equal sized broadcast antenna and rectenna, both would be 4-5 Kilometers across. (Longer in the east-west dimension if the satellite was at a high angle from zenith.) Transfer efficiency would probably be somewhere between 25% and 50%.

    The classic formula given at the 1975 conference was Dd=2*pi*R*Lambda, where D and d are the diameters of the sending and receiving antennas (apertures), R is the distance, and Lambda is the wavelength. With these dimensions, effectively all of the energy sent will be received in the rectenna.

    As for the price of launch, I covered that above:

    Costwise, there are several things to consider. First, economies of scale will lower the price of launch to orbit by several orders of magnitude. Second, the entire launch and setup cost doesn’t create a system of power satellites, it creates a system of factories to make power satellites, using power and mass already away from earth. Once that factory system is built, the actual mass of power satellites will be many orders of magnitude greater than what was launched into orbit.

  35. 535
    Dave Rado says:

    Re. #530, AK, fascinating, although I wish there was a bit more detail in the articles about exactly how they hope to cope with sandstorms, and how they get their projected numbers (such as “our potential in thermal solar power is four times the world’s energy consumption”).

    I heard a report on the radio recently that in some recent climate talks leading up to Bali, the developing world countries (G20?) were trying to forge a common negotiating position for Bali, and were stymied in their attempt to do so by countries like Saudi Arabia insisting that they would only sign up on condition that they receive “compensation” for their expected loss of revenue resulting from the future increased use of renewable energy!

    Now it seems to me that if the Saudis (et al) were to change their demand subtly to saying that the “compensation” they are asking for should take the form of investment by the West in large solar projects in the Middle Eastern oil producing countries similar to the Algerian project, under some sort of offsetting scheme, then they’d be onto a winner.

  36. 536
    AK says:

    One energy storage option I haven’t seen discussed is Flywheel energy storage

    This option is currently used mostly in vehicles, despite many disadvantages. As a mass-produced stationary storage system, it could probably be gotten up and running within a few years. It requires no exotic materials for construction (although many modern flywheels are made of graphite composites). There is some danger of explosion, as with any power storage system, but such explosions are entirely mechanical (no nasty combustion products), and safety precautions would be much easier in a static large facility than a vehicle.

  37. 537
    Dave Rado says:

    Re. RodB, #533:

    re 519: “…what is the potential viability or otherwise of putting a huge bank of photovoltaic solar panels in the Sahara and supplying electricity to Africa, Europe and parts of Asia from it?…”

    You still have the (now MASSIVE) storage problem and would lose tremendous amount of power through transmission even with DC.

    I imagine the Algerians must have already thought of that (see #530), and must believe they have an answer to it. And they seem to have invested many millions in it already, so it’s not just blue sky. But I wish there were an article about the Algerian project that covered that sort of issue in detail.

  38. 538
    James says:

    Re #23: […the reactor is Areva’s “next generation” European Pressurized Reactor (EPR) design, which is presumably representative of the new standardized reactors…]

    So it’s the first of the type. There are going to be problems building the first one of anything. You work out the problems on #1, so #2 has fewer problems. By the time you’re at #10 or so, you’ve learned how to build that design well & quickly.

    The important point is that we know they can be built, and will work, unlike most of the proposed alternatives.

  39. 539

    re 519. 92 square miles of solar thermal electric generation would power todays US electrical needs. See: http://www.ausra.com/. They claim 3% of the land area of Morocco would supply the electrical energy needs of Europe. Not sure if this includes transmission losses. They are projecting they can deliver electricity (with storage) at competitive prices as they ramp up US production.

  40. 540
    Matt says:

    #516 dhogaza: No, he’s not being mealy-mouthed. Extinction is typically a gradual event, and we don’t usually know exactly when a particular species goes extinct even for species we’ve named.

    His first statement (“doomed to immediate or early extinction”) could be said to be true regardless. It’s a meaningless statement.

    I could say: “Your driving is horrible. You are doomed to a car crash next week, or at some point in the future.”

    You can never prove that statement wrong unless you die an old man without having been in a crash. It’s a meaningless statement to make, whether it’s about cars or extinctions.

    His second statement (“the annual loss is in the tens of thousands”) in isolation is provably wrong; it’s alarmist. So, he’s got all bases covered. He can use the clearly wrong, alarmist statement whenever he wants, then when he’s called to the rug for some measure of accountability, he simply brings out the full statement.

    He’s argued from teh same vantage point for better than 30 years. Just curious, but at what point will you concede “Yeah, it looks like he was a bit pessimistic”. In 100 years if we’re still at current extinction rates? 200 years? 500 years? Even in a thousand years his kin can still be arguing how prescient great grandpa was–even if current rates are still in tact.

    Name one that was in trouble due to habitat loss that has rebounded without intense (and very costly) human intervention to restore habitat?

    Why limit to habitat loss? None of the original statements were specifically about habitat loss.

    Google for “thought to be extinct” and you get ivory billed woodpecker, Yangtze river dolphin, Siamese crocodiles, South China Tiger, Wollemi pine, Harlequin frog, Madagascar Pochard, Vietnamese Javan Rhino, Diatomyidea, and on and on.

    People thought there were zero, then they found some. Presumably, they weren’t spending money on saving somethign they previously had thought was exctinct. So, we can say these rebounded without any human intervention, no?

    Actually, just for fun, name noe that has rebounded WITH intense (and very costly) human intervention to restore habitat?

    Again why limit to habitat loss? Google “saved from extinction” and you get another long list. Praried dog, whooping crane, grizzly bear, bald eagle, gray wolf, green sea turtle, key deer, florida panther, kirtland’s warbler. And on and on.

    It will differ for every species at risk, which is why it is incredibly stupid for you to expect a precise answer in a general statement about global extinction.

    I don’t expect a precise answer. But I do expect an answer that has some tie back to reality. There’s a reason the UN reports things differently than Wilson and Lovejoy. And there’s a reason Gore cites Wilson and Lovejoy rather than the UN. You know that too.

  41. 541
    mg says:

    #511. James asks why nuclear power plants need to be decomissioned. It is a question of sea level rise risk.

    Take Hansen’s BAU sea level rise estimate of 5 metres plus by 2100 (for example see
    http://environment.newscientist.com/article.ns?id=mg19526141.600&feedId=climate-change_rss20 )
    and put 5 metres into here

    http://flood.firetree.net/

    to check against the locations of nuclear reactors installations which are given here

    http://www.insc.anl.gov/pwrmaps/

    Arial pictures of each nuclear installation can also be viewed using Google Earth.

    Assuming 5 metres by 2100, one might assume perhaps 3 metres by 2050 for BAU (especially as the GIS is exhibiting ice quakes growing at something like 5th power).

    Redo the above risks assessments with 3 metres SLR by 2050. (NB risk assessment does not means prediction; it means risk assessment of a potential scenario).

    The risks of huge sea levels on decadal time scales suggest that the nuclear industry needs to go back to its risk assessment exercises for each and every plant and urgently consider whether for each and every plant a premature (ie before-end-of-life) decommissioning needs to carried out. Plant subject to SLR-induced inland quakes also need to be reassessed.

    For those industries that use energy sourced from nuclear, an assessment needs to be made of the ways in which high-impact energy conservation and alternative energy (consider renewables!!!!!) backfill is delivered to cover the sea-level-rise induced nuclear gap.

    Avoiding the nuclear risks should to be top priority.

    Emergency mitigation should be top priority.

    United Nations IPCC sea level rise team: please reconvene full-time as an emergency measure.

  42. 542
    Joe Duck says:

    Intelligence is pervasive in nature, and other “intelligent life forms” are all around us. What they lack is the particular, synergistic evolutionary developments that have enabled the human species to develop advanced technologies to exploit and manipulate our “environment”

    An important point, nicely put…

    I have not got out to buy “Cool it” but have had a nice email exchange with Kare Fog in Denmark who thinks the 1.5 Million “cold deaths” comes from extrapolating for a larger population than was examined by Keatinge et al available here:
    http://www.bmj.com/cgi/reprint/321/7262/670

    Fog’s extensive criticism of that approach is here:
    http://www.lomborg-errors.dk/coolitBchap2heat.htm

    My take remains as above – the issue is not some absurdity like “AGW is on balance a good thing because we’ll have fewer dead people from the cold”, rather it is “alarmism is bad”. He’s reasonably suggesting that most media accounts, and even some scientists, focus almost exclusively and narrowly on events with a trivial AGW component (European heat wave, Lake Chad, Katrina) while excluding events and circumstances that do not support the idea that AGW peril is imminent and consequences will likely be catastrophic.

  43. 543

    Re #531 Matt:

    With >100 dB path loss

    Path loss? We’re talking beam propagation here. 85% transmission efficiency has been demonstrated — see the Wikipedia article, e.g. Or were you really thinking of bathing the whole country / planet in a microwave power field? :-)

  44. 544
    jbroon says:

    RE#540
    Matt said:
    “Google for “thought to be extinct” and you get ivory billed woodpecker, Yangtze river dolphin, Siamese crocodiles, South China Tiger, Wollemi pine, Harlequin frog, Madagascar Pochard, Vietnamese Javan Rhino, Diatomyidea, and on and on.

    People thought there were zero, then they found some. Presumably, they weren’t spending money on saving somethign they previously had thought was exctinct. So, we can say these rebounded without any human intervention, no?”

    Actually, no we can’t say they “rebounded”. The Yangtze dolphin is functionally extinct (circa 2006. There is an unconfirmed sighting in 2007). There are less than 30 South China tigers in the wild(according to Wikipedia). The Javan Rhino recovery is hindered by continual habitat loss. The 10,000$ reward for the discovery of an Ivory Billed Woodpecker nest is still waiting to be claimed, and there has been no “definitive” sighting of the woodpecker either, according to the Cornell Lab of Ornithology.

    You need to choose your words more carefully.

  45. 545

    SecularAnimist writes:

    [[That’s not true. There are plenty of other intelligent life forms with whom we share the Earth — for example, non-human primates, birds and dolphins. All of them have been shown to have language, reasoning ability, and culture. At least some of them have basic mathematical skills. Non-human primates and birds make and use simple tools, and teach their young to do so. Some non-human primates and some birds have learned to communicate intelligently using human languages (sign language in the case of primates, and spoken English in the case of birds).]]

    True. There is, however, a difference in the level of intelligence. Intelligence, by performance on problem-solving tests, seems to follow encephalization quotient, and while EQ is 7.3 for humans, is is only 5.8 for dolphins, 2-3 for great apes and 1-2 for birds such as parrots. No animal makes fire other than man, although several (apes, monkeys, raccoons) have hands and eye-hand coordination.

  46. 546

    James writes:

    [[[How much carbon emissions will they eliminate?] However much is generated by the coal-fired plants they replace.]]

    Not quite. Nuclear plants use large quantities of cement, and machines used in mining uranium are generally fossil-fuel powered. There would be technical problems switching them to electric; those machines need to generate a lot of energy fast.

  47. 547

    Can someone comment on this just out on the E-Wire: Rising Sea Levels: Science Fiction. at: http://www.ewire.com/display.cfm/Wire_ID/4347. I will be speaking soon in New Jersey and will surely be questioned about it.

    Re 541. One meter of sea level rise would be catastrophic for the US. See full page ad in the NY Times yesterday “America: Nowhere to Hide” at: http://www.architecture2030.org/pdfs/NY_Times_111207.pdf (it will take a minute to open the file, lots of graphics)

  48. 548

    AK writes:

    [[While on the subject of solar powered satellites, what is the potential viability or otherwise of putting a huge bank of photovoltaic solar panels in the Sahara and supplying electricity to Africa, Europe and parts of Asia from it?

    I’ve never seen a formal analysis, but in addition to the obvious socio-political problems, just one word: sandstorms.]]

    Another word: Shovels.

    Sandstorms don’t occupy the majority of space or time in deserts. They will certainly add to wear and tear on the facilities and will cause some downtime. I would imagine they would therefore add to downtime and to maintenance and replacement costs. Will the addition be fatal to the project? My guess would be not, but has anyone studied the question?

  49. 549
    Nick Barnes says:

    Matt @ 540: your short lists of endangered and rescued creatures are all, or nearly all, megafauna. The great majority of species in the world are not(*). It is relatively easy to prevent extinction of a megafauna species, because most such species have wide ranges some part of which can be protected.
    Consider instead the many millions of species of insect in tropical rainforests. Many of these species are known from a very small number of specimens, and of course most species are not known at all. The ranges of the known species are hard to measure, although models suggest that power laws are at work, and that many have ranges of just a few square kilometres or even less. Cut down the range and the species is wiped out.

    (*) I recall reading a paper suggesting that the majority of eukaryotic species in the world are nematode worms and other microfauna living in sea-bottom sediments, but we just don’t know.

  50. 550
    Nick Barnes says:

    As far as solar power satellites are concerned, it’s plainly absurd without far cheaper and more reliable launch technologies. So why don’t the SPS advocates come back once we’ve got that wrinkle ironed out?
    I’m quite prepared to believe that it’s the power technology of the 22nd century, but there’s no way it’s going to save us from ourselves in the next couple of decades.
    During those decades, I’m all for spending some of our aerospace subsidy on developing cheaper and simpler launch technology (Google will show me advocating this on sci.space and elsewhere nearly 20 years ago). Rather than, say, ballistic missile defense.
    In the meantime, we actually have plenty of solar energy down here on the earth’s surface. Let’s build some big CSP plants in the hot deserts.


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