Casting doubt on fusion power

Metal fence in front of electrical station

Looking at a diagram of a proposed fusion reactor, it is easy to get the false sense that such technologies will provide clean and inexpensive power within a few decades: fusing tritium and deuterium to produce heat, while generating new fuel from lithium using the neutrons produced.

A post on The Oil Drum enumerates the many technical challenges associated with achieving that aim, going so far as to say that dreams about fusion power should be ‘ended’ as a consequence. Written by Dr. Michael Dittmar, a researcher with the Institute of Particle Physics of ETH Zurich, the article enumerates a number of significant problems:

  • Large amounts of tritium are required and various problems exist with it as a material and a fuel.
  • Materials from which reactor walls can be made are unavailable, and far beyond anything that is available.
  • Many obstacles exist to breeding tritium from Lithium-6.
  • Similarly, obstacles exist to extracting tritium from the lithium blanket and delivering it in a pure form into the chamber where fusion is occurring.
  • Reactors may not be able to breed enough tritium to keep themselves going, much less provide excess tritium for new facilities.

While this may not be cause for declaring fusion a complete non-starter, it is at least a useful way to temper the assumption that fusion power will emerge any decade now, providing a pain-free solution to the problems of climate change and fossil fuel depletion.

The article also lists problems with fission reactors that breed plutonium or use thorium as fuel: both options mooted in response to concerns about limited availability of uranium for use in conventional reactors. All this is a reminder that – while renewables may be costly and have intermittency problems to manage – there is every reason to believe they can be practically deployed starting immediately.

Anthropogenic climate change: evidence from isotopic ratios

Back in 2003, Prosenjit Ghosh and Willi Brand described one of the more clever ways in which the link between fossil fuel combustion and the accumulation of carbon dioxide in the atmosphere has been demonstrated. In their article “Stable isotope ratio mass spectrometry in global climate change research” (PDF), they discuss how the ratio of isotopes of carbon in the atmosphere can be used to identify the sources of atmospheric CO2. Their work was published in 2003, in the International Journal of Mass Spectrometry.

By tracking the ratio of carbon-12 to carbon-13 in the atmosphere, the distinctive imprint of fossil fuel combustion can be identified. This is really just confirmation of the inevitable chemical fact that burning coal, oil, and natural gas produces CO2. Nevertheless, it is nice to have an independent line of evidence showing that human activities really are the major cause behind observed increases in the atmospheric concentration of CO2.

The IPCC, climate, and consensus

Leaf and branches

In addition to sketching out the borders of reasonable debate on climate change, Mike Hulme has written some intelligent things on scientific consensus, as embodied in the Intergovernmental Panel on Climate Change (IPCC) reports:

[T]he use of consensus is merely one (structured) way of distilling evidence – evidence which might be somewhat ambiguous, incomplete or contradictory or where there is latitude for genuine differences of interpretation – into an overall agreed statement on an issue of scientific or public importance.

He also quotes an intelligent comment from a volume by P.N. Edwards and S.H. Schneider:

We have discussed earlier… why it may often be necessary for science to use consensus processes as a way of consolidating knowledge so that it can be useful for policy. Consensus knowledge, by construction, will always allow experts to disagree, with knowledgeable opinion existing at either tail of the distribution of views… Such scientific consensus is not ultimate ‘truth’ and, on occasion, may turn out to be wrong. But the alternatives to the IPCC style of consensus-building are even less likely to command widespread authority within the worlds of science and policy. ‘Vastly better [than random solicitation of views] is the work of groups like the IPCC… which although slow, deliberative, sometimes elitist and occasionally dominated by strong personalities, are nonetheless the best representation of the scientific community’s current general opinion.’

The big problem, from a policy perspective, is the number of politically influential agents who either continue to deny that potentially dangerous anthropogenic climate change is taking place, or who argue for various reasons that nothing ought to be done about it. The fact that these people don’t have views that are reconcilable with the best available evidence doesn’t mean they aren’t able to influence the public policy debate.

The boundaries of reasonable climate change debate

In his well-argued book Why We Disagree About Climate Change, Mike Hulme does a good job of establishing the boundaries of the legitimate debate about climate change and what we ought to do about it:

Many of the disagreements that we observe are not really disputes about the evidence upon which our scientific knowledge of climate change is founded. We don’t disagree about the physical theory of absorption of greenhouse gases demonstrated by John Tyndall, about the thermometer readings first collected from around the world by Guy Callendar, or about the possibility of non-linear instabilities in the oceans articulated by Wally Broecker. We disagree about science because we have different understandings of the relationship of scientific evidence to other things: to what we may regard as ultimate ‘truth,’ to the ways in which we relate uncertainty to risk, and to what people believe to be the legitimate role of knowledge in policy making.

That’s as good a concise summary as I’ve seen. If the people you are debating accept that temperatures are rising, that greenhouse gasses cause warming, and the the climate system may react to human emissions in deeply disagreeable ways, you are within the realm where reasonable discussions can occur. By contrast, if your partners in discussion assert that climate is not changing, greenhouse gasses have nothing to do with it, and that any change will surely be benevolent and gradual… well… here be dragons.

“Coal is the enemy of the human race”

Primary colours on wooden crates

The above wording is blogger David Roberts‘ attempt to summarize the relationship between humanity and coal in the 21st century. While many countries rely on it to produce electrical power and fuel other sorts of industry, there are huge negative externalities associated with it as a power source. These include:

  • Environmental destruction and contamination from coal mining.
  • Human health impacts from coal mining
  • Air pollutant emissions from coal burning, including particulate matter and mercury
  • Greenhouse gas emissions from coal burning
  • Toxic coal ash

A report from the US National Research Council found that American coal plants produce $62 billion per year in negative externalities, before climate impacts are taken into account.

Climate change is the biggest danger associated with coal. Firstly, coal produces a lot of CO2 per unit of useful energy. Secondly, coal reserves are so enormous that burning a significant fraction of what is left would essentially guarantee more than 2°C of mean warming globally, the level scientists and policy-makers have generally accepted as ‘dangerous.’

If it can prove safe, cheap, and effective, there may be a future for carbon capture and storage (CCS). Until that is demonstrated, we cannot assume that there is a future for coal as an energy source. Even before you take the climate impacts into consideration, the total costs are unfavourable compared to greener and renewable alternatives. Once climate change is factored in, the case against non-CCS coal becomes conclusive.

[16 February 2010] Now that I have a fuller understanding of the importance of not burning coal and unconventional fossil fuels, because of their cumulative climatic impact, I have launched a group blog on the topic: BuryCoal.com. Please consider having a look or contributing.

Long-lived nuclear waste warnings

In addition to the engineering problems involved in storing radioactive wastes from power plants and weapons programs, there is the additional difficulty of marking the storage sites as dangerous, in a manner that will be comprehensible throughout the period in which the wastes will be a hazard. In 1991, a report considered this question: “Expert Judgment on Markers To Deter Inadvertent Human Intrusion Into the Waste Isolation Pilot Plant.”

As reported in Slate:

“The report’s proposed solution is a layered message—one that conveys not only that the site is dangerous but that there’s a legitimate (nonsuperstitious) reason to think so. It should also emphasize that there’s no buried treasure, just toxic trash. Here’s how the authors phrase the essential talking points: “[T]his place is not a place of honor … no highly esteemed deed is commemorated here.” Finally, the marker system should communicate that the danger—an emanation of energy—is unleashed only if you disturb the place physically, so it’s best left uninhabited.”

They estimate that a system of redundant warning markers for an American nuclear waste dump would cost about $68 million.

The whole issue is a potent demonstration of the challenges contemporary technologies create, when it comes to our moral relationship with future generations. Just as they will be the ones who live with the climate change we produce, they will also have legacies like topsoil erosion and the accumulation of toxic and radioactive wastes to contend with.

Strategy for denier commenters

Man with power saw

I am happy to say that traffic to this site has been steadily increasing. Visits are up 138% from last year, and October was our best month ever. Increasingly, a sibilant intake of breath is well ranked by search engines.

One problematic element that accompanies popularity is that I attract ever-more climate change deniers and delayers (those who accept that it is real, but think we should take no action). Ordinarily, I am happy to debate with people and try to provide quality information. That being said, it can take up a lot of time to try to refute those who repeat faulty arguments over and over. These people call themselves ‘skeptics,’ but I think they are mis-applying the term. I have yet to encounter one that is willing to back away from even thoroughly discredited positions. Instead, they just move on to another misleading argument.

The question, then, is how to deal with these commentors without losing all scope for socializing and personal projects. Some of the options:

  1. Briefly assert that their position is incorrect and point to a resource that says why. Ignore further attempts at rebuttal.
  2. Point all such commentors towards pre-existing posts and conversations, without offering specific responses.
  3. Adopt the Zero Carbon Canada approach: “ATTN climate change denier trolls: you are cooking our kids and will be deleted.”
  4. Continue to provide detailed, personalized responses as much as possible.

(1) and (2) are appealing because they reduce the extent to which one person seeking to spread disinformation can waste my time. That said, leaving comments unaddressed could lead readers to believe that the points made therein are valid. (3) is appealing because it would prevent bad information from appearing online, though it is obviously a form of censorship. (4) is the ideal world solution, though I do need to wonder whether refuting deniers and delayers in blog comments is really the best use of my time, even if all I am taking into consideration is whether I am acting effectively on climate change.

Which option do readers think is most suitable? Are there other options I ought to consider?

Debates within society at large, and within the scientific community

Elaborating on work discussed here before, Gavin Schmidt provides some information on what distinguishes the most recently developed sorts of climate models for their predecessors, such as General Circulation Models. The newer Earth System Models:

now include interactive atmospheric chemistry, aerosols (natural and anthropogenic) and sometimes full carbon cycles in the ocean and land surface. This extra machinery allows for new kinds of experiments to be done. Traditionally, in a GCM, one would impose atmospheric composition forcings by changing the concentrations of the species in the atmosphere e.g. the CO2 level could be increased, you could add more sulphate, or adjust the ozone in the stratosphere etc. However, with an ESM you can directly input the emissions (of all of the relevant precursors) and then see what ozone levels or aerosol concentrations you end up with. This allows you to ask more policy-relevant questions regarding the net effects of a particular sector’s emissions or the impact of a specific policy on climate forcing and air pollution.

Atmospheric chemistry is clearly a highly complex field. This makes it all the more strange and troubling that such a vast divide exists between debate between experts in the scientific community and debate within society at large.

That said, I suppose these situations aren’t really all that rare. Serious geologists and biologists continue to work out the minutiae of the history of present status of the Earth, at the same time as laypeople and self-styled ‘experts’ maintain debates about whether the world is 6,000 years old and whether all the creatures on it have existed since the beginning of time. By the same token, no matter how sophisticated scientific modeling of the climate becomes – and how much data accumulates demonstrating human-induced warming – there will still be people willing to baldly assert that climate change isn’t happening / is natural / isn’t a problem / is beneficial / is caused by sunspots, etc.

Wetlands and greenhouse gas emissions

Red maple leaf on grass

A recent report from Wetlands International provides a global overview of greenhouse gas (GHG) emissions from wetlands. Neither their present state nor their total greenhouse gas holdings are comforting. Indonesia is the world’s most substantial emitter of GHGs from peat, with annual emissions of 500 million tonnes of carbon dioxide (CO2). That is about 2/3 of Canada’s total emissions. When it comes to stock, Canada leads the world with a troubling 155 billion tonnes of CO2 embedded in peat, enough to add 569 billion tonnes of CO2 to the atmosphere. In total, the 0.3% of the world’s land surface covered by drained peat already generates about 6% of global emissions.

This reinforces two points about climate change mitigation:

  1. Firstly, we need to pay attention to land use changes as well as fossil fuel use, when it comes to cutting down the amount of GHGs humanity is adding to the atmosphere, eventually stabilizing at zero net emissions.
  2. Secondly, if we create enough warming, there are huge stocks of carbon that could be released, pushing that process even further. Pushing the climate system to the point where positive feedbacks become dominant would commit us inescapably to significant additional warming, over and above that created through direct human actions.

While policies like a carbon tax to discourage emissions are a critical part of the solution, humanity needs to accept that our overall physical and biological impact on the planet is so large that we need to give serious consideration to how our collective policies and individuals choices are affecting the future of the climate. Recognizing the carbon intensity of drying marshland is a small but important part of that.

Re-pondering a low-carbon cross country voyage

I am delighted to say that I will be able to take the time from Saturday December 19th through Sunday January 10th off work. Naturally, the thing to do is go to Vancouver, as I was unable to do over the summer.

Options:

Train

  • Comfortable, can walk around
  • Reasonable chance of getting some reading and other sorts of work done
  • Probably access to an electrical outlet
  • Probably half to 1/3 the greenhouse gas emissions of flying
  • Takes four days
  • Leaves three times a week: Saturday, Tuesday, and Thursday from Toronto and Friday, Sunday, and Tuesday from Vancouver
  • Expensive: $1,100 for a non-refundable ticket
  • Note, if the Sierra Youth Coalition still has a 40% discount, that is a more reasonable $660.

Bus

  • Pretty uncomfortable
  • Not much chance of getting anything done – little space for books and/or laptop
  • Probably no access to an electrical outlet
  • Even fewer greenhouse gas emissions
  • Takes three days
  • Seems to leave every day
  • Cheap: $224 for a ticket that can be changed for a small fee

The train would certainly be much more comfortable and romantic, but is it worth paying nearly five times as much (and two extra days) for?

As a follow-up question, why are our trains so slow and expensive?