Stabilization Wedges (Part 2)

Okay. We’re going through this paper, which you can read yourself:

• Stephen Pacala and Robert Socolow, Stabilization wedges: solving the climate problem for the next 50 years using current technologies, Science 305 (2004), 968-972.

The paper lists 15 ‘wedges’, each of which could ramp up to reducing carbon emissions by 1 gigaton/year by 2054. We’re going through all these wedges and discussing them. And the Azimuth Project is lucky to have a new member on board — Frederik De Roo — who is summarizing our discussion here:

• Azimuth Project, Stabilization wedges.

So, let’s get going!

Last time we covered four wedges related to energy conservation and increased efficiency. Wedge 5 is in a category of its own:

5. Shifting from coal to natural gas. Natural gas puts out half as much CO2 as coal does when you burn them to make a given amount of electricity. After all, it’s mainly methane, which is made from hydrogen as well as carbon. Suppose by 2054 we have coal power plants working at 90% of capacity with an efficiency of 50%. 700 gigawatts worth of coal plants like this emit 1 gigaton of carbon per year. So, we can reduce carbon emissions by one ‘wedge’ if we replace 1400 gigawatts of such plants with gas-burning plants. That’s four times the 2004 worldwide total of gas-burning plants.

Wedges 6-8 involve carbon capture and storage:

6. Capturing CO2 at power plants. Carbon capture and storage at power plants can stop about 90% of the carbon from reaching the atmosphere, so we can get a wedge by doing this for 800 GW of coal-burning power plants or 1600 GW of gas-burning power plants by 2054. One way to do carbon capture and storage is to make hydrogen and CO2 from fossil fuels, burn the hydrogen in a power plant, and inject the CO2 into the ground. So, from one viewpoint, building a wedge’s worth of carbon capture and storage would resemble a tenfold expansion of the plants that were manufacturing hydrogen in 2004. But it would also require multiplying by 100 the amount of CO2 injected into the ground.

7. Capturing CO2 at plants that make hydrogen for fuel. You’ve probably heard people dream of a hydrogen economy. But it takes energy to make hydrogen. One way is to copy wedge 6, but then ship the hydrogen off for use as fuel instead of burning it to make electricity at power plants. To capture a wedge’s worth of carbon this way, we’d have to make 250 megatons of hydrogen per year from coal, or 500 megatons per year from natural gas. This would require a substantial scale-up from the 2004 total of 40 megatons of hydrogen manufactured by all methods. There would also be the task of building the infrastructure for a hydrogen economy. The challenge of injecting CO2 into the ground would be the same as in wedge 6.

8. Capturing CO2 at plants that turn coal into synthetic fuels. As the world starts running out of oil, people may start turning coal into synfuels, via a process called coal liquefaction. Of course burning these synfuels will release carbon. But suppose only half of the carbon entering a synfuels plant leaves as fuel, while the other half can be captured as CO2 and injected underground. Then we can capture a wedge’s worth of CO2 from coal synfuels plants that produce 1.8 teraliters of synfuels per year. For comparison, total yearly world oil production in 2004 was 4.7 teraliters.

Now: What are the pros and cons of these four wedges? What is the biggest thing that Pacala and Socolow overlooked?

I’m puzzled about the last wedge. Pacala and Socolow say 1 gigaton carbon/year is the flow of carbon in 24 million barrels/day, or 1.4 teraliters/year. They assume the same value for synfuels and allow for imperfect capture, which leads them to conclude that carbon capture at synfuels plants producing 1.8 teraliters/year of synfuel can catch 1 GtC/year. But this calculation doesn’t make sense to me. If we’re catching just half the carbon, and 1 GtC/year = 1.4 teraliters oil/year, don’t we need to generate at least twice that — 2.8 teraliters synfuel/year — to catch wedge’s worth of carbon?

I’m also unclear what percentage of the carbon you can actually capture while turning coal into synfuels. Can you really capture half of it?

There’s also another funny feature of this last wedge. If we assume people are already committed to making synfuels from coal, then I guess it’s true, they’ll emit less carbon if they use carbon capture and storage as part of the manufacturing process. But compared to making electricity or hydrogen as in wedges 6 and 7, turning coal into synfuels seems bound to emit more carbon, even with the help of carbon capture and storage.

In general, it only makes sense to talk about how much carbon emission some action prevents when we compare it to some alternative action. That’s pretty obvious, but it gets a bit confusing when some of Pacala and Socolow’s wedges look like plausible alternatives to other ones.

Another question: how does carbon capture and storage work, actually? Summarizing Pacala and Socolow, I wrote:

One way to do carbon capture and storage is to make hydrogen and CO2 from fossil fuels, burn the hydrogen in a power plant, and inject the CO2 into the ground.

But I’d like to learn the details!

This entry was posted on Tuesday, November 23rd, 2010 at 6:36 am and is filed under carbon emissions, energy. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

63 Responses to Stabilization Wedges (Part 2)

  1. umass1993 says:
    23 November, 2010 at 7:29 am

    These wedges make sense to me.

    1) Shifting from coal to natural gas would involve banning the use of coal to some degree or another. This would be effective because the carbon in the coal would remain in the ground.

    2) Carbon capture would be effective bcause the energy would be extracted but the carbon would be artificially reseqestered in the ground.

    Carbon stored in the ground is not in the air and will not contribute to the greenhouse effect.

    The main problem with these wedges is political. Like any effective solution, all these wedges involve raising the price of energy, either by removing certain sources of eneryg from the plate, or by making energy extraction a more difficult and expensive process.

    IMO, wedges 5-8 would help contain global climate change because, unlike wedges 1-4, 5 through 8 would limit the amount of carbon that could be released into the atmosphere.

    Reply
  2. Frederik De Roo says:
    23 November, 2010 at 8:17 am

    I think the implementation of wedge 5 remains unclear. How will a shift from coal to natural gas be implemented? Forbid coal-mining? (seems impossible to me) Taxing the use of coal? Then, when natural gas becomes more scarce, prices will rise, and coal-mining will become economical again (unless, e.g. taxes also rise simultaneously). But maybe the question is whether that process would happen before or after 2054.
    Furthermore, I think many countries will not want to shift from coal to gas out of strategical reasons. So I think it’s better to focus on carbon capture from existing coal plants – if this process is feasible – or to find ways to reduce energy consumption.

    Reply
    • John Baez says:
      23 November, 2010 at 9:13 am

      A lot of Western countries are shifting away from using coal themselves… but instead they’re shipping it to China, which is probably even worse as far as CO2 emissions are concerned.

      From the 23 November 2010 International Herald Tribune:

      Even as developed countries close or limit the construction of coal-fired power plants out of concern over pollution and climate-warming emissions, coal has found a rapidly expanding market elsewhere – in Asia, particularly China.

      At ports in Canada, Australia, Indonesia, Colombia and South Africa, ships are lining up to to load coal for furnaces in China, which has evolved virtually overnight from a coal exporter into one of the world’s leading purchasers.

      Traditionally, coal is burned near where it is mined – particularly so-called thermal or steaming coal, used for heat and electricity. But in the past few years, long-distance international coal exports have been surging because of China’s galloping economy, which now burns more than half of the 6 billion tons of coal used globally each year.

      As a result, not only are the pollutants that developed countries have tried to reduce finding their way into the atmosphere anyway, but ships chugging halfway around the globe are spewing still more.

      And the rush to feed this new Asian market has helped double the price of coal over the past five years…

      Reply
      • umass1993 says:
        23 November, 2010 at 11:45 am

        instead they’re shipping it to China, which is probably even worse as far as CO2 emissions are concerned

        This makes no sense to me. As far as the other pollutants are concerned, China could be worse, but not CO2.

        As far as the developed nations go, they have been in recession for a couple of years, so …

        Reply
        • Frederik De Roo says:
          23 November, 2010 at 12:02 pm

          I think there are more carbon emissions because of the transport.

          traditionally coal is burned near where it is mined

          in the past few years, long-distance international coal exports have been surging

        • John Baez says:
          23 November, 2010 at 12:06 pm

          Right, the point was that if some countries use gas here because coal is ‘bad’, but then they ship that coal to China, more CO2 is emitted by the transportation process. I’m not sure how significant this effect is — but it’s at least ironic.

    • umass1993 says:
      23 November, 2010 at 11:59 am

      Unless artificial carbon sequestration is done, forbidding certain types of mining will be necessary to curb global warming. It is that simple.

      The best things to forbid would be those fossil fuels that have a low energy net yield, (such as oil sands) and those fuels that require particularly environmentally damaging mining techniques (such as mountain top removal).

      The moral of the story is that the only thing that matters is how much carbon is in the ground. So either we leave the fuels there, or we take the energy and replace the carbon. It’s that simple. Talking about anything else is just useless beating around the bush (IMNSHO)

      Reply
      • Frederik De Roo says:
        23 November, 2010 at 2:20 pm

        The reason I am sceptical about the chances of success of ‘forbidding’ is that nations cannot even agree on reducing overfishing, so I doubt that individual countries that have coal mines would voluntarily stop mining coal (and cutting off a temporal source of wealth) if other countries friendly asked them.

        Reply
        • Frederik De Roo says:
          23 November, 2010 at 2:29 pm

          Just a crazy idea: perhaps the money of a carbon tax could be used to fund an organization that rents mines from coal producing countries, and solely for the purpose of not using them in the next 50 yrs.

        • Tim van Beek says:
          23 November, 2010 at 2:42 pm

          Just a crazy idea:…

          It’s not that crazy, the EU has paid farmers for not producing milk, butter or not tilling their fields. (I’m trying to get paid for not programming any computers, but have failed so far :-)

      • John Baez says:
        24 November, 2010 at 2:35 am

        umass1993 wrote:

        The moral of the story is that the only thing that matters is how much carbon is in the ground. So either we leave the fuels there, or we take the energy and replace the carbon.

        I basically agree. I’d say it like this: if we want to stop global warming, we have to either leave carbon in the ground, sequester it somehow, or engage in some other form of geoengineering.

        (I include geoengineering to include all the alternatives I know: I’m not trying to get into a discussion of geoengineering right now. And I say other forms of geoengineering because it could be argued that a really huge carbon sequestration project, e.g. using biochar, counts as a form of geoengineering.)

        It’s that simple. Talking about anything else is just useless beating around the bush (IMNSHO).

        Well, I don’t think it’s ‘simple’ to get people to leave fossil fuels in the ground, or sequester lots of carbon, or figure out a reasonably safe form of geoengineering. All these alternatives involve big decisions, and the details will be very complex.

        For example, you can say we should ban coal mining — it’s very simple to say this — but it will only actually happen if we show people a viable alternative to what they’re doing now: how to use less energy, and use more forms of energy that don’t put CO2 into the atmosphere. And this is very complex.

        Anyway, I appreciate your comments on all these wedges, and I think I understand your frustration.

        Reply
  3. Harvey Brown says:
    23 November, 2010 at 8:31 am

    Frederik De Roo’s skepticism about the shift from coal to natural gas is reinforced, at least for the short term and specifically in relation to China, in James Fallows’ thoughtful and provocative recent essay “Dirty Coal; Clean Future” in the Atlantic Magazine:. At any rate, readers interested in the problem of implementation of wedges 5 and 6 should find the essay of interest.

    Reply
    • John Baez says:
      24 November, 2010 at 2:40 am

      Thanks for the tip, Harvey! The article is here:

      • James Fallows, Dirty coal, clean future, Atlantic, December 2010.

      December already! He must be a man ahead of his time — slightly, anyway.

      Reply
    • John Baez says:
      24 November, 2010 at 3:00 am

      Good article! Here are some particularly relevant bits:

      Overall, coal-burning power plants provide nearly half (about 46 percent this year) of the electricity consumed in the United States. For the record: natural gas supplies another 23 percent, nuclear power about 20 percent, hydroelectric power about 7 percent, and everything else the remaining 4 or 5 percent. The small size of the “everything else” total is worth noting; even if it doubles or triples, the solutions we often hear the most about won’t come close to meeting total demand. In China, coal-fired plants supply an even larger share of much faster-growing total electric demand: at least 70 percent, with the Three Gorges Dam and similar hydroelectric projects providing about 20 percent, and (in order) natural gas, nuclear power, wind, and solar energy making up the small remainder. For the world as a whole, coal-fired plants provide about half the total electric supply. On average, every American uses the electricity produced by 7,500 pounds of coal each year.

      So, he argues, it’s hopeless to quit burning coal anytime soon — so we need to do it better.

      What would progress on coal entail? The proposals are variations on two approaches: ways to capture carbon dioxide before it can escape into the air and ways to reduce the carbon dioxide that coal produces when burned. In “post-combustion” systems, the coal is burned normally, but then chemical or physical processes separate carbon dioxide from the plume of hot flue gas that comes out of the smokestack. Once “captured” as a relatively pure stream of carbon dioxide, this part of the exhaust is pressurized into liquid form and then sold or stored. Refitting an existing coal plant can be very costly. “It’s like trying to remodel your home into a mansion,” a coal-plant manager told me in Beijing. “It’s more expensive, and it’s never quite right.” Apart from research projects, only two relatively small coal-fired power plants now operate in America with post-combustion capture.

      Designing a capture system into a plant from the start is cheaper than doing refits. But even then the “parasitic load” of energy required to treat, compress, and otherwise handle the separated stream of carbon dioxide can come to 30 percent or more of the total output of a coal-fired power plant—so even more coal must be burned (and mined and shipped) to produce the same supply of electricity. Without mandatory emission limits or carbon prices, burning coal more cleanly is inevitably more expensive than simply burning coal the old way. “When people like me look for funding for carbon capture, the financial community asks, ‘Why should we do that now?’” an executive of a major American electric utility told me. “If there were a price on carbon”—a tax on carbon-dioxide emissions—“you could plug in, say, a loss of $30 to $50 per ton, and build a business case.”

      “Pre-combustion” systems are fundamentally more efficient. In them, the coal is treated chemically to produce a flammable gas with lower carbon content than untreated coal. This means less carbon dioxide going up the smokestack to be separated and stored.

      Either way, pre- or post-, the final step in dealing with carbon is “sequestration”—doing something with the carbon dioxide that has been isolated at such cost and effort, so it doesn’t just escape into the air. Carbon dioxide has a surprisingly large number of small-scale commercial uses, starting with adding the sparkle to carbonated soft drinks. (This is not a big help on the climate front, since the carbon dioxide is “sequestered” only until you pop open the bottle’s top.) All larger-scale, longer-term proposals for storing carbon involve injecting it deep underground, into porous rock that will trap it indefinitely. In the right geological circumstances, the captured carbon dioxide can even be used for “enhanced oil recovery,” forcing oil out of the porous rock into which it is introduced and up into wells.

      These efforts are in one way completely different from “advanced research and development” as we often conceive of it, and in another way very much the same. They are different in that the scientists and entrepreneurs involved do not seem to count on, or even hope for, the large breakthroughs we have come to assume in biological sciences and info-tech.

      Instead of big breakthroughs, he argues that we need the incremental improvements that come when you’re actually doing something on a large scale. And that’s where China comes in:

      In the search for “progress on coal,” like other forms of energy research and development, China is now the Google, the Intel, the General Motors and Ford of their heyday—the place where the doing occurs, and thus the learning by doing as well. “They are doing so much so fast that their learning curve is at an inflection that simply could not be matched in the United States,” David Mohler of Duke Energy told me.

      “In America, it takes a decade to get a permit for a plant,” a U.S. government official who works in China said. “Here, they build the whole thing in 21 months. To me, it’s all about accelerating our way to the right technologies, which will be much slower without the Chinese.

      “You can think of China as a huge laboratory for deploying technology,” the official added. “The energy demand is going like this”—his hand mimicked an airplane taking off—“and they need to build new capacity all the time. They can go from concept to deployment in half the time we can, sometimes a third. We have some advanced ideas. They have the capability to deploy it very quickly. That is where the partnership works.”

      How it works:

      Ten years ago, at the end of the Clinton administration, the Chinese and American governments signed a “Fossil Energy Protocol,” to coordinate research on better use of coal and oil. Political leaders have come and gone since then, but the cast of technicians, civil servants, and business officials on each side has been relatively stable and has gotten used to working together. After taking office as secretary of energy last year, Steven Chu—a celebrity in China because of his Chinese heritage and his Nobel Prize—gave a new push to these efforts, hiring additional staff members for the U.S.-China office and committing $75 million to a joint Clean Energy Research Center.

      The efforts of two scientists we’ve already met, Julio Friedmann and Ming Sung, illustrate what Americans can and cannot do to shape what happens in China—and the mounting advantages on China’s side relative to America’s.

      Friedmann, who is in his mid-40s, has become one of the world’s experts on sequestration: how and where carbon dioxide can safely be stored underground. He was trained in geology at MIT and the University of Southern California and initially went to work for ExxonMobil. But by the early 2000s he had become fascinated with the emerging science of underground carbon-dioxide storage. “At that point, it was clear that nearly all of the really cool work was being done in the national labs,” he told me. In 2004 he and his family moved from Maryland to California, where he joined Lawrence Livermore. He is now the head of the Carbon Management Program there and the technical leader of a government-university-business consortium that this summer won a Department of Energy competition to help develop carbon-sequestration projects in China. To give an idea of the consortium’s range, it includes three universities, three national laboratories, two scientific nongovernmental organizations, and six large corporations, among them General Electric, Duke Energy, and AEP.

      What Julio Friedmann does:

      On a typical trip to China, he will spend half his time in Beijing or Shanghai, meeting with government and corporate officials—and the other half in Xi’an or the Inner Mongolian wilderness, where many of the most promising storage locations are found. What he and his team have to offer, from the American part of the supply chain, is expertise on geological formations, on computer models for how the “plume” of liquefied carbon dioxide will settle into porous rock, and on other benefits of America’s decades of experience in petroleum geology. He can also put Chinese plant managers, scientists, and bureaucrats in touch with overseas counterparts they would otherwise never meet. “Projects like these are sort of like the school dance,” he told me. “You’re not getting married, but you’re figuring out how to interact. We need to start the process in a way that gives people the confidence to do it again, and again, and again. The confidence is the product.” The more often Chinese and foreign officials work together, the more easily they continue to work together. This might sound trivial, but I’ve become convinced that the steady expansion of these contacts will make a major difference in how an ever more powerful China deals with the rest of the world. What does Friedmann, or the United States, get from the process? “More tons sequestered, rather than emitted, in China,” he told me. But also something unavailable in America: a chance to see new technology in new plants and learn how it works. “In the U.S. today, there is not a single demonstration of capturing CO2 from a coal-fired plant at large scale,” he said. “The technologies have been a little too expensive to actually implement. That’s why we started looking at China.” They can afford to build, and Americans can hope to watch and learn.

      What Ming Sung’s ‘Clean Air Task Force’ does:

      In the early 2000s the task force, originally a conventional anti-air-pollution group, embraced the necessity of cleaning up coal. In Beijing, Sung gave me a copy of its latest working paper, in both Chinese and English, called “Coal Without Carbon.”

      The group has sponsored research on sequestration, on post-combustion capture, and on the “cleanest” of the emerging pre-combustion coal technologies—“underground coal gasification.” In this process, jets of air (or pure oxygen), sometimes with steam or various chemicals, are blasted into coal seams deep underground. They interact chemically with the coal to produce a gas that flows back up a pipe and can be burned. It leaves in the ground much of the carbon, sulfur, nitrogen, and other elements that create greenhouse gases and other pollutants when coal is burned.

      “And this can be very cheap,” Sung told me. “You don’t have to mine the coal. You don’t have to send men underground or haul coal around or dispose of ash. All the dirty stuff stays buried.” Because of these and other savings, he said, coal used this way could match or beat the price of today’s standard dirty power plant.

      But in advocating the whole range of “clean coal” technologies, Sung and his team have the same problem Julio Friedmann has with carbon sequestration: it’s not happening in the United States. There’s one significant exception: the Texas Clean Energy Project, a plant being built outside Odessa, which will apply underground-gasification technology to capture 90 percent of its carbon, more than any other commercial plant in the world. It received a $450 million federal award, just over half from the Department of Energy’s Clean Coal Power Initiative and the rest from the American Recovery and Reinvestment stimulus program (toward the $2.1 billion total capital cost). If it works as promised, this facility will be an advance over any coal-fired plant operating anywhere: it will gasify coal underground, eliminating the cost and damage of mining; it will sell urea (for fertilizer) and other chemical by-products of the underground gasification; and it will use the captured carbon dioxide for enhanced oil recovery in the nearby Permian Basin oil fields—all in addition to generating power. [Correction: The decarbonization and other cleanup steps that make this plant distinctive are done above rather than underground. For full details, see texascleanenergyproject.com/about-tcep.]

      There’s a lot more, but this gives you a flavor. Thanks again, Harvey Brown! I’ve added some of this material to Carbon capture and storage at the Azimuth Project.

      Reply
  4. Tim van Beek says:
    23 November, 2010 at 11:33 am

    A naive question: Pacala and Socolow state that their wedges are based on technologies we already have, but has anyone tried to capture and store carbon on a big scale?

    On Serendipity Steve has posted about another wedge, population dynamics.

    Reply
    • John Baez says:
      23 November, 2010 at 11:51 am

      Good question, Tim. Does anyone hear know about carbon capture and storage?

      For now let me just quote what Pacala and Socolow said about their 6th wedge. They mention a Norwegian carbon capture and storage project called ‘Sleipner’:

      The scale of the storage part of this wedge can be expressed as a multiple of the scale of current enhanced oil recovery, or current seasonal storage of natural gas, or the first geological storage demonstration project. Today, about 0.01 GtC/year of carbon as CO2 is injected into geologic reservoirs to spur enhanced oil recovery, so a wedge of geologic storage requires that CO2 injection be scaled up by a factor of 100 over the next 50 years. To smooth out seasonal demand in the United States, the natural gas industry annually draws roughly 4000 billion standard cubic feet (Bscf) into and out of geologic storage, and a carbon flow of 1 GtC/year (whether as methane or CO2) is a flow of 69,000 Bscf/year (190 Bscf per day), so a wedge would be a flow to storage 15 and 20 times as large as the current flow. Norway’s Sleipner project in the North Sea strips CO2 from natural gas offshore and reinjects 0.3 million tons of carbon a year (MtC/year) into a non–fossil-fuel–bearing formation, so a wedge would be 3500 Sleipner-sized projects (or fewer, larger projects) over the next 50 years.

      Reply
      • Tim van Beek says:
        23 November, 2010 at 12:00 pm

        The problem with this statement is that there is no information about the safeness of the storing ground. If oil companies use CO2 injection to get out more oil, how much time and money did they spend in investigation how long the CO2 stays underground?

        :-)

        The reason for my scepticism is that in Germany people have not succeeded to find a suitable storage area for nuclear waste, one that is convincingly safe for at least the next 10 000 years. And paradoxically nuclear waste cannot explode, the worst that can happen is that it leaks into the environment, but what happens when an underground CO2 storage violently decompresses?

        Reply
      • umass1993 says:
        23 November, 2010 at 12:03 pm

        There is also the thought of deep sea CO2 injection. At large depths, you get liquid CO2 that stays at the ocean bottom. You may want to indulge yourself in some of that literature.

        Reply
        • Tim van Beek says:
          23 November, 2010 at 12:50 pm

          umass1993 :

          You may want to indulge yourself in some of that literature.

          Sure, but I don’t know what that literature would be, if you know of some references we could add those to the Azimuth wiki.

          For example, the article about the safeness of the “Sleipner project” (linked to from the picture John posted) closes with this statement, which is mysterious to me:

          The injected CO2 will potentially be trapped by geochemical processes. Solubulity trapping has the effect of eliminating the buoyant forces that drive CO2 upwards, and through time it can lead to mineral trapping, which is the most permanent and secure form of geological storage.

          What is “solubulity trapping”, what is “mineral trapping”, how is it possible to forecast that it will happen and why is it secure?

        • Nathan Urban says:
          23 November, 2010 at 1:18 pm

          Solubility trapping is where the CO2 dissolves in water. It’s harder for the CO2 to escape the reservoir when it’s dissolved, rather than just sitting on top of water in a light buoyant phase. The solution itself sinks deeper and more securely into the reservoir, because it’s heavier with CO2 in it.

          Mineral trapping is where the CO2 chemically reacts with minerals so that carbon gets sequestered in stable, solid precipitates.

          A random collection of references, discussing trapping mechanisms and sometimes failure modes: link, link, link, link, link.

      • John Baez says:
        23 November, 2010 at 12:17 pm

        Tim wrote:

        The problem with this statement is that there is no information about the safeness of the storing ground.

        Did you click on the picture?

        The reason for my scepticism is that in Germany people have not succeeded to find a suitable storage area for nuclear waste, one that is convincingly safe for at least the next 10 000 years.

        Here I agree with Stewart Brand: it’s absurd to demand a way of storing nuclear waste that’s “convincingly safe for at least 10 000 years”. There is no way to predict what will happen in 10 millennia. Quite likely people will want to use that nuclear waste as fuel long before 10 000 years have gone by.

        If you want to stop anything, just demand that its effects be provably safe for the next 10 000 years.

        Meanwhile approximately 750,000 Chinese die per year from pulmonary disease, in large part due to coal-fired plants, but nobody gives a fuck about that.

        People are not very rational about risk.

        Reply
        • Tim van Beek says:
          23 November, 2010 at 12:31 pm

          Did you click on the picture?

          No, sorry :-)

          People are not very rational about risk.

          Yes, I know, but it is a fact that this topic about “safe storage” has been on the front of the whole discussion of nuclear power. Partly because the nuclear supporters claimed that this is not a problem at all.

        • John Baez says:
          23 November, 2010 at 12:41 pm

          I agree that people need to study the safety issues for carbon sequestration, don’t get me wrong. I also think people need to take the waste issue seriously for nuclear power. However, I think some people are stuck in an irrational mode on the latter issue, where their knee-jerk responses prevent a balanced analysis of the risks, where you consider the risks associated to not doing something along with the risks of doing it. I hope that doesn’t happen with carbon sequestration.

        • Tim van Beek says:
          23 November, 2010 at 12:42 pm

          Partly because the nuclear supporters claimed that this is not a problem at all.

          I meant to say that the supporters of nuclear power put themselves into a bad tactical position by claiming that it is not a problem to find a storage ground that is provable safe for at least 300 000 years, instead of explaining that it is not necessary to find one.

        • John Baez says:
          23 November, 2010 at 12:45 pm

          Now it’s up to 300 000 years, eh? A few minutes ago you said 10 000 years. What’ll it be tomorrow?

          Seriously, I think we agree here.

        • Tim van Beek says:
          23 November, 2010 at 12:52 pm

          Now it’s up to 300 000 years, eh? A few minutes ago you said 10 000 years. What’ll it be tomorrow?

          Originally they claimed that 300 000 years does not pose a problem, but failed to come up with a storage facility that is “provable safe” for even 10 000 years (which is termed an “intermediate storage facility”).

  5. John F says:
    23 November, 2010 at 3:53 pm

    I don’t have any confidence in high volume injection over the long term. Our species has been geologically injecting at all only about 50 years. The ground underneath our feet is not in homogeneous layers, contrary to the cartoons comprising most all modeling, and even if it were there are unpredictable side effects at any given site. If you’ve been following the news about fracking, you’re aware that the most experienced corporations with the most economic incentives to do things right environmentally fail miserably because they do not really understand even shallow injection.
    http://www.vanityfair.com/business/features/2010/06/fracking-in-pennsylvania-201006
    Of course leaking, contamination, etc is to be expected (rational i.e. calculated risks). What is not being reported is volcanos of fracking fluids kilometers from injection sites. They scratch their heads, close that well, and move over horizontally a little bit.

    It’s all the more uneasily amusing when you consider that we still don’t do, for example, even septic systems with any degree of reliability. It’s the stuff of cargo cults. Regardless of right percoloation tests, right leach field preparation, the right bacteria, and all the other right stuff, *all* continuous-use adsorption fields clog within a couple of decades.

    Reply
  6. Hank Roberts says:
    23 November, 2010 at 4:49 pm

    Worry seems to be that old oil and gas fields will have had lots of old wells drilled over time — often not mapped or recorded — plugged with concrete and abandoned, and increasing CO2 pressure will accelerate failure.
    http://www.google.com/search?q=gas+well+concrete+plug+co2+damage

    Reply
  7. G.R.L. Cowan, H2 energy fan 'til ~1996 says:
    23 November, 2010 at 7:47 pm

    You can’t go very deep in the ocean without the density of pure CO2 becoming greater than that of the local seawater.

    I seem to recall reading of natural abyssal CO2 lakes but so far have found report of only those tiny man-made ones.

    Reply
  8. G.R.L. Cowan, H2 energy fan 'til ~1996 says:
    23 November, 2010 at 7:53 pm

    That was an attempt to link to page 6, which contains figure 8.2, a photograph of the pools.

    Reply
  9. John F says:
    23 November, 2010 at 8:10 pm

    John B,
    In a National Academies review there is an article entitled “Sequestration via Injection of Carbon Dioxide into the Deep Earth” with some details
    http://www.nap.edu/openbook.php?record_id=10798&page=17

    Reply
  10. Frederik De Roo says:
    23 November, 2010 at 10:27 pm

    About CO2 escaping from a reservoir, there is e.g. the natural disaster of Lake Nyos in 1986 (but here the solution was supersaturated).

    Reply
  11. streamfortyseven says:
    23 November, 2010 at 10:53 pm

    Here’s something else to do with the CO2:

    http://en.wikipedia.org/wiki/Methanol_economy

    namely:

    More importantly, methanol can also be produced from CO2 by catalytic hydrogenation of CO2 with H2 where the hydrogen has been obtained from water electrolysis. Methanol may also be produced through CO2 electrochemical reduction, if electrical power is available. The energy needed for these reactions in order to be carbon neutral would come form renewable energy sources such as wind, hydroelectricity and solar as well as nuclear power. In effect, all of them allow free energy to be stored in easily transportable methanol, which is made immediately from hydrogen and carbon dioxide, rather than attempting to store energy in free hydrogen.

    CO2 + 3H2 → CH3OH + H2O

    CO2 +2H2O + electrons → CO + 2H2 (+ 3/2 O2) → CH3OH

    The necessary CO2 would be captured from fossil fuel burning power plants and other industrial flue gases including cement factories. With diminishing fossil fuel resources and therefore CO2 emissions, the CO2 content in the air could also be used. Considering the low concentration of CO2 in air (0.037%) improved and economically viable technologies to absorb CO2 will have to be developed. This would allow the chemical recycling of CO2, thus mimicking nature’s photosynthesis.

    The best citation I’ve seen so far is this:
    http://pubs.acs.org/doi/abs/10.1021/jo801260f

    and here’s the list from the wiki article:

    1. George A. Olah (2005). “Beyond Oil and Gas: The Methanol Economy”. Angewandte Chemie International Edition 44 (18): 2636–2639. doi:10.1002/anie.200462121. PMID 15800867.

    2. George A. Olah (2003). “The Methanol Economy”. Chemical Engineering News 81 (38): 5.

    3. George A. Olah, G. K. Suray Prakash, Alain Goeppert (2009). “Chemical Recycling of Carbon Dioxide to Methanol and Dimethyl Ether: From Greenhouse Gas to Renewable, Environmentally Carbon Neutral Fuels and Synthetic Hydrocarbons”. Journal of Organic Chemistry 74 (2): 487–498. doi:10.1021/jo801260f. PMID 19063591.

    4. Beyond Oil and Gas: The Methanol Economy, George A. Olah, Alain Goeppert, G. K. Surya Prakash, Wiley-VCH, 2006

    Reply
    • John Baez says:
      24 November, 2010 at 3:59 am

      Thanks! I’ve used some of this information to start a new Azimuth Project page, Methanol economy.

      Obviously I’ll need to revisit a lot of these topics someday… I can’t really absorb information this fast, but that’s one thing the wiki is good for — it’s like a holding area for my brain.

      I wish I could tell: is this methanol economy really a good idea, or just a diversion?

      Reply
      • Jon Frankis says:
        25 November, 2010 at 9:36 am

        Can I suggest an extension of the category to “Alcohol economy”, generally? The similarities as fuels between meth-, eth- and butanol to name but three are greater than their differences relative to gasoline or diesel. Ethanol has a number of advantages over methanol (some disadvantages) and is the one that already has a significant commercial presence in the fuel economy.

        Reply
        • John Baez says:
          25 November, 2010 at 12:47 pm

          Please post a nice long comment packed with information about the other alcohols! I’ll gladly add that information to the Azimuth Project and change the page title of Methanol economy to something broader, or add other pages.

          Changing the title of a page is really easy. Getting information is a bit harder. Understanding it and writing it up nicely is what really takes time. So, I’m hoping everyone here, with their various forms of technical expertise, will post insightful comments with good links.

          Certainly at some point we’ll have developed a big page on ethanol. It’s not there yet.

          We do have a bit on Biofuel.

        • Jon Frankis says:
          25 November, 2010 at 1:05 pm

          OK, perhaps we should start with the Wikipedia page on the fuel ethanol economy that contains “Brazil is considered to have the world’s first sustainable biofuels economy … There are no longer any light vehicles in Brazil running on pure gasoline …” http://en.wikipedia.org/wiki/Ethanol_fuel_in_Brazil ?

          And for butanol: “Like ethanol, biobutanol is a liquid alcohol fuel that can be used in today’s gasoline-powered internal combustion engines. The properties of biobutanol make it highly amenable to blending with gasoline. It is also compatible with ethanol blending and can improve the blending of ethanol with gasoline. The energy content of biobutanol is 10 to 20 percent lower than that of gasoline.

          Under U.S. Environmental Protection Agency (EPA) regulations, biobutanol can be blended as an oxygenate with gasoline in concentrations up to 11.5 percent by volume (i.e., the EPA considers blends of 11.5% or less biobutanol with gasoline to be “substantially similar” to pure gasoline). Blends of 85 percent or more biobutanol with gasoline are required to qualify as an EPAct alternative fuel. Biobutanol proponents claim that today’s vehicles can be fueled with high concentrations of biobutanol—up to 100%—with minor or no vehicle modifications, although testing of this claim has been limited.”
          Dept of Energy: http://www.afdc.energy.gov/afdc/fuels/emerging_biobutanol_what_is.html

        • Frederik De Roo says:
          25 November, 2010 at 1:42 pm

          Shouldn’t we be careful to copy the use of the world “sustainable” in sentences taken from wikipedia, such as:

          Brazil is considered to have the world’s first sustainable biofuels economy

          I scrolled down the referred wikipedia page and also found:

          The authors found a “biofuel carbon debt” is created when Brazil and other developing countries convert land in undisturbed ecosystems, such as rainforests, savannas, or grasslands, to biofuel production, and to crop production when agricultural land is diverted to biofuel production. This land use change releases more CO2 than the annual greenhouse gas (GHG) reductions that these biofuels would provide by displacing fossil fuels.

          and

          A report released by Oxfam in June 2008 criticized biofuel policies of rich countries as neither a solution to the climate crisis nor the oil crisis, while contributing to the food price crisis. The report concluded that from all biofuels available in the market, Brazilian sugarcane ethanol is “far from perfect” but it is the most favorable biofuel in the world in term of cost and greenhouse gas balance.

          I didn’t read the report yet.

        • frankis says:
          25 November, 2010 at 8:22 pm

          I think it’s to the credit of the Wikipedia page that it makes that qualification about “sustainable” biofuels, yes. For instance there’d be no reason I can think of for applauding a biofuel business that proposed to raze virgin Amazon rainforest to plant sugarcane.

          The Wikipedia page goes further: “In order to guarantee a sustainable development of ethanol production, in September 2009 the government issued by decree a countrywide agroecological land use zoning to restrict sugarcane growth in or near environmentally sensitive areas such as the Pantanal wetlands, the Amazon Rainforest and the Upper Paraguay River Basin.[178][179][180] The installation of new ethanol production plants will not be permitted on these locations, and only existing plants and new ones with environmental licensed already approved before September 17, 2009, will be allowed to remain operating in these sensitive areas. According to the new criteria, 92.5% of the Brazilian territory is not suitable for sugarcane plantation. The government considers that the suitable areas are more than enough to meet the future demand for ethanol and sugar in the domestic and international markets foreseen for the next decades”.
          http://en.wikipedia.org/wiki/Ethanol_fuel_in_Brazil#Deforestation

        • frankis says:
          25 November, 2010 at 10:56 pm

          ps not wishing to sidetrack this thread any more than necessary my point was that we might attempt to group similar things together as simply as possible (not too simply).

      • John Baez says:
        27 November, 2010 at 2:30 pm

        Thanks, Jon! I have started a page called Alcohol on the Azimuth Project and have dumped some of the information you provide into this page. It’s very preliminary – what the Wikipedia people call a ‘stub’. If you want to add more, just click ‘Edit’ at the bottom of the page and type stuff in! Don’t worry too much about getting the format right (unless you’re a perfectionist), we can fix things up.

        Reply
      • streamfortyseven says:
        28 November, 2010 at 11:49 pm

        I don’t think it’s just a “diversion”  because you can do a lot of other things with methanol besides burning it. It’s a feedstock and precursor for lots of organic compounds. On page 247 of Beyond Oil and Gas: The Methanol Economy”, Olah, Goeppert, and Surya Prakash, Wiley-VCH (2006), ISBN 3-527-31275-7, the following list:

        Methanol —->   Formaldehyde  —-> Isoprene (precursor to rubber)
                             Methyl Tertiary-butyl Ether
                             Acetic Acid, and Acetic Anhydride
                             Ethanol
                             Chloro- and Halomethanes

                             Methyl Methacrylate
                             Methyl Formate
                             Methyl Amines

                             Dimethyl Terephthalate —->  polyethyleneterephthalate (PET)
                             Dimethyl Ether   —->  polyunsaturated hydrocarbons

        Reply
    • Florifulgurator says:
      24 November, 2010 at 12:20 pm

      Looks quite interesting. The methanol economy is the first technological idea that gets me excited.

      1) It might serve as an incentive to invest in CO2 underground storage, so the CO2 could later be used as methanol.

      2) It could help as an energy storage system for fluctuating renewable power.

      Of course it’s not as good as CO2 non-production or final sequestration, but re-using the damned molecule could perhaps help a lot.

      Questions: 1) How is the energy / released CO2 ratio doing when methanol is produced from CCS using zero-CO2 renewable energy?

      1.1) Perhaps nothing is won over just burning the coal without CO2 capture and methanol production?

      2) Can methanol production be localized? (Ship CO2 in bottles to small local methanol producer in hinterland?)

      Reply
      • streamfortyseven says:
        25 November, 2010 at 7:38 am

        If you were to build the coal-fired electric power plant within a couple of miles of the mine, transport costs would go down, and you could use the coal-bed methane (that’s the gas which killed those miners in New Zealand) and react it with the CO2 produced at the power plant to make methanol on the spot. The only thing left to do is to put the electrical power on the grid… But then you may have to deal with transmission losses. This last point I think may have been dealt with some years back… And if you can burn the coal near the mine, you can put the ash back in the mine and not have to worry about groundwater contamination.

        Reply
        • streamfortyseven says:
          25 November, 2010 at 7:52 am

          You know, this might be an answer to the problem they’re having in Siberia with the methane bubbling out of the lakes and melting permafrost, capture it and react it with CO2 on the spot, and make methanol, which would be a relatively clean-burning fuel… Or solvent, or feedstock for longer chain hydrocarbons or biodiesel or whatever.

        • Frederik De Roo says:
          25 November, 2010 at 9:05 am

          methane (…) and react it with the CO2 produced at the power plant to make methanol on the spot

          what’s the chemical reaction you are thinking of? Methane and methanol have the same number of both C’s and H’s, so the CO2 on the lhs should lead to carbon and oxygen on the right. But carbon on the right seems a bit strange to me if you say that the carbon dioxide was produced by burning coal…
          (well, I guess I should find a decent chemistry textbook)

        • streamfortyseven says:
          25 November, 2010 at 6:39 pm

          I’ve got Olah’s book at home, but I’m away for Thanksgiving; I’ve got to meet with a client back home tomorrow, so I’ll post something then. To the best of my recollection, it’s some sort of catalytic disproportionation reaction, with methane as a source of hydrogen.

        • streamfortyseven says:
          28 November, 2010 at 11:29 pm

          OK, I could have sworn that there was a disproportionation reaction to produce methanol from methane and CO2, and there is on page 241 of “Beyond Oil and Gas: The Methanol Economy”, Olah, Goeppert, and Surya Prakash, Wiley-VCH (2006), ISBN 3-527-31275-7, the following:

          Methane Decomposition      CH4  —->  C   +  2H2   (900degC, no air or N2)

          Methanol Synthesis           CO2  +  3H2  —->  CH3OH  +  H2O

          Overall Reaction              3CH4 +  2CO2  —–>  2CH3OH + 2H2O + 3C

          There’s already chemistry being done in flow reactors in industrial flue gases to reduce nitric oxides – and the same thing goes on in catalytic converters in cars:

          http://www.energysolutionscenter.org/boilerburner/Workshop/RCTFlueGasTreatment.htm

          And these flue gases are at the ideal temp for methane decomposition, so maybe the way to go about this is to run the coal bed methane, which is usually flared off, through a heat exchanger running alongside the flue to bring its temperature up to that of the flue gas, then do the decomposition, collect the molecular carbon as carbon black (which might contain a fair amount of fullerenes), and then react the hot H2 with the flue gases, comprised mostly of nitric oxides and CO2, to get ammonia/urea compounds, water (as superheated steam) and methanol. Run this mixture through a condenser and you could get reagent-grade methanol, distilled water, ammonia, and urea, all of which are useful… See http://en.wikipedia.org/wiki/Urea for example.

  12. Phil Henshaw says:
    24 November, 2010 at 7:47 pm

    Regarding John Baez’ comments above:

    There seems to be a clear answer for who to charge for CO2 impacts when they occur in China for products sold elsewhere. I developed a rigorous “whole systems” scientific method that captures nominally five times as much carbon content in products as the direct energy use tracing methods do.

    The party to charge the carbon cost to is the purchaser of the service it provides, and you can determine the true scale of that with the right scientific method. It’s a method that the ISO and LCA standards DO NOT FOLLOW. I use a physical causation analysis that exposes a quite large error in the standard method of energy cost accounting:

    Click to access WindEROI_SEA.pdf

    In addition, I have been told by lawyers who know the tariff laws, that it would NOT violate tariff treaty agreements to assign products coming from china a fee in proportion to their carbon content… if you could fairly measure it. I think my method allows that.

    phil

    Reply
  13. Jon Frankis says:
    24 November, 2010 at 11:50 pm

    Continue to burn fossil fuels and maybe we can do something about CO2 emissions? What about the various other negative externalities of a fossil fuel economy?

    The one plausible way of sequestering carbon from fossil fuels and avoiding the various ill-effects of extracting, shipping, distributing and burning them is to leave them in the ground.

    Technologies reach the end of their useful lifetimes. When sufficient of the vested interests have died off or wised up the world moves on.

    The least stupid aspect of the whole category of hypothetical carbon capture schemes is that it’s addressing only one negative externality of fossil fuels, in a world full of them.

    Reply
  14. umass1993 says:
    25 November, 2010 at 9:49 am

    This is a link to James Hansen’s latest thoughts on global warming.

    Click to access 20101122_ChinaOpEd.pdf

    He makes a couple of policy recommendations that are notable in 2 ways.

    1) He does NOT menttion efficiency as being part of the solution. He DOES mention using price as a mechanism for inducing change, however.

    2) He DOES mention leaving as much fossil fuels in the ground as possible. He mentions TAR SANDS in particular.

    Like I wrote before, I emailed Prof. Hansen a few years ago and encouraged him to take my point of view. It is very rewarding to me to see that most authoritative figure in global climate change may have been affected by my opinion.

    Reply
    • Nathan Urban says:
      25 November, 2010 at 1:27 pm

      I went to a talk by Hansen last week. He did mention efficiency. But he thinks efficiency alone won’t accomplish anything without a price on carbon, since a cheap source of energy will continue to be used no matter how much energy we use.

      The editorial repeats what he said in his talk: “as certain as gravity”, fossil fuels will be burned as long as they’re cheaper than the alternatives, so they need to become more expensive. His goal is to leave carbon in the ground, not just burn it more slowly.

      Hansen has been arguing for years for a moratorium on building new coal plants, and a phaseout of all coal. He mentioned tar sands too. I can’t say where he got his ideas from. In his talk he seemed to be emphasizing carbon pricing more than outright bans on anything, as he has in the past. He has talked about “tax and dividend” before. (I guess he’s more strategically calling it “fee and dividend” nowadays.)

      I believe John has read Hansen’s book, so he might fill in with some of his views, although they have been evolving with time.

      Reply
  15. Jonathan Vos Post says:
    28 November, 2010 at 11:01 pm

    Los Alamos’s magazine, Nov 2010, “Metagenomics”

    “Researchers envision a variety of practical applications to come from metagenomics in the future, with many of these applications addressing critical human needs. In each of the following examples, rapid metagenomic studies of the relevant microbial community could allow us to duplicate, harness, or expand upon the special capabilities of microbes.
    Medicine: Many drugs in widespread use today, such as antibiotics, derive from microbes or plants, but most of this natural biodiversity remains untapped. Metagenomic exploration of the remaining biodiversity could lead to the rapid discovery of new medicines. Additionally, the community of bacteria living in and on the human body, especially in the intestine, plays a major role in the regulation of human health. Using metagenomics to examine this community could vastly improve our understanding of nutrition and disease.”

    “Climate: A bacterial group called cyanobacteria, largely in the oceans, performs about half of all photosynthesis on Earth. That, together with carbon cycling by soil microorganisms, exerts a substantial influence on the atmosphere and therefore the climate. Metagenomics is already helping us begin to understand the role of microbes in climate change and may help us identify species and enzymes capable of slowing or reversing that change.”

    Metagenomics to the Rescue

    “Bioenergy: Cellulosic ethanol, a renewable fuel resource, is manufactured from plant cellulose found in agricultural waste, such as corn stalks, wheat straw, and switchgrass. Microbes working together are used to first turn cellulose into sugars and then ferment those sugars into cellulosic ethanol fuel. Metagenomics can provide the additional information we need to learn how to adapt microbial fuel production to widespread application.

    Agriculture: Soil microbes are known to protect plants from disease and to provide them with nutrients, as when they convert atmospheric nitrogen gas into useable ammonia. Such abilities might someday be manipulated
    for improved crop output, but first we need metagenomic analysis to improve our understanding of these complex community activities.
    Environment: Much natural and human-made waste is beneficially processed by microbes. Gasoline, for example, leaks from the fuel tanks under many gas stations and enters our groundwater. But our drinking water is made safe by microorganisms, and the same capability could be exploited to clean up larger-scale environmental damage, such as oil spills. Metagenomics could allow us to identify the microbes and the waste treatment processes needed to handle the ever-expanding collection of chemicals…”

    Reply
  16. Jonathan Vos Post says:
    6 December, 2010 at 11:34 pm

    Globalization means that Earth’s life-support system can no longer be treated as separate from the socio–economic system, says Sybil Seitzinger

    “In Frank Herbert’s 1965 science-fiction classic Dune, the number-one position on the planet is held not by a politician, but by a planetary ecologist. His job is to oversee the long-term conversion of the desert planet to a lush biosphere — a role demanding formidable far-sightedness.”

    “On Earth, the human population is set to top 9 billion within two generations. Meanwhile, we are altering, in profound and uncontrolled ways, key biological, physical and chemical processes of ecosystems on which this growing population will depend. Gordon Conway, former head of the Rockefeller Foundation, once suggested that Earth should appoint a planetary ecologist of its own. Given that today’s policy-makers have consistently demonstrated an inability to take more than a short-term view of life on Earth, perhaps it is time to take the idea seriously.”

    “The number-one position on Earth at present is arguably that of head of the United Nations (UN). Ban Ki-moon, the current UN secretary-general, seems to understand the scale and nature of the problem much better than his predecessors. This is welcome, but is still not enough. Indeed, it is doubtful whether a UN system shackled by national self-interest can ever set out a vision for a sustainable planet, or a sensible plan to realize it.”

    “Policy-makers must take on board that Earth’s ecology acts as a complex and nonlinear system, and is in a constant state of change. And they must recognize that to fully understand this system, they need to take a long-term view. Is this so different from acknowledging the complexity and timescales of the world economy?…”

    Reply
  17. Stabilization Wedges (Part 4) « Azimuth says:
    16 January, 2011 at 11:15 am

    […] 1 of this series we talked about four wedges involving increased efficiency and conservation. In Part 2 we covered one about shifting from coal to natural gas, and three about carbon capture and storage. […]

    Reply
  18. Darin says:
    23 January, 2011 at 11:04 pm

    Apparently fugitive gas emissions have a very high GWP, so it may not present as great an advantage even having a lower carbon intensity than coal. At the very least we would need strict guidelines for measuring and regulating fugitive emissions for it to be an effective alternative to coal.

    http://www.cypenv.org/world/Files/methane.htm

    Reply

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