As is always the case in debates about technologies that do not yet exist, other experts have found reasons to disagree with the conclusions of the APS report, for instance:
Klaus S. Lackner, a physicist and director of the Lenfest Center for Sustainable Energy at Columbia University’s Earth Institute who created the company’s technology, criticized the American Physical Society study as too narrowly focused, saying it had analyzed only outdated technology.I very much agree with this last sentiment, as I explain in detail in The Climate Fix which has a lengthy discussion of air capture (which has chemical, biological and geological technologies, APS deals just with a subset of the chemical approaches).
Dr. Lackner said his design, which uses a plastic that absorbs carbon dioxide when dry and releases it to the air when wet, would eventually be capable of capturing the gas for far less than $600 a ton.
“I can assure you that if I believed it would cost $600 a ton, I would have given up long ago,” he said.
Mr. David of Kilimanjaro Energy also said the report had failed to take into account the use of captured carbon dioxide as a feedstock for biofuels, like those made from algae.
“What we’re into is making fuels,” he said. “If you can grab CO2 from the atmosphere and can do it economically, you can find yourself in the midst of the fuel business.”
Mr. Desmond, a co-chairman of the report, said his group had struggled to get sufficient data from private companies engaged in research into direct air capture. In the absence of data, claims that the process could be done cheaply were almost impossible to verify, he said.
“In the big scheme of things, those numbers don’t seem credible,” he said. “That’s my concern.”
Other analysts had mixed views. In an e-mail message, Sasha Mackler, director for energy innovation at the Bipartisan Policy Center, a Washington institute, agreed that direct air capture of carbon dioxide was probably decades away from making economic sense. But the market for alternative fuels could make the process far more profitable than forecast in the report, Mr. Mackler said.
“We are at far too early a stage to predict how this field will emerge in the years ahead,” he said.
“Now is not the time to be taking options off the table.”
As far as dueling cost estimates for technologies that do not exist? Call me a skeptic, but I'd prefer to evaluate technologies based on how they perform in the real world, not in expert reports or even peer reviewed papers. As I have written elsewhere on air capture technologies, "There is little point in debating specific details about costs or large-scale feasibility until demonstration projects are undertaken" (PDF).
On air capture, chemical or otherwise, we should be skeptical until the technology is proven in practice. Until then, air capture should certainly be a part of a broad-based technology innovation portfolio.
5 comments:
I think that I accidentally deleted this msg from roderick, sorry:
"Having spent thirty years in stock markets, I've seen more ventures attempting to go from laboratory desk (or small scale testing) to the real world environment on a commercial scale than most people have had hot dinners. That, after all, is part of the honourable purpose of the stock market, to fund businesses. Even stripping out the charlatans, whether one could see in advance or only with hindsight, I can barely recall any that succeeded, although some must have done.
There's a Finnish nickel mine out there at the moment, using small-scale results of bio-heap-leaching to develop the largest nickel mine and metals recovery plant in the world, accessing grades previously deemed uneconomic. A great idea, great venture, but four years after floating they haven't got it to work, the grades coming out the other side are roughly half what they expected.
So in my world I'd rephrase Roger's sceptical, I mean realistic, sentence as follows:
'As far as dueling cost estimates for technologies not yet proven? Call me a skeptic, but I'd prefer to evaluate technologies based on how they perform in the real world, not in research reports or Offering Memorandums.'"
Scientifically, the APS report is very well done. Thanks for posting the link.
My take home lesson is the estimate of efficiencies, going beyond the easily calculated thermodynamic minimum (which already requires a forbidding amount of energy). The report indicates there will be a substantial multiplier for any known technology, as well as major complications as the capture medium is degraded/contaminated. At the moment, any clean energy with which you could run a carbon capture facility would be better used displacing a coal fired power plant. And we are still, both technologically and economically, a long way from reaching the break-even point, even on paper, let alone in the real world.
Roger,
It seems to me that the most promising form of air capture at this point is biochar. Lehmann et al from Cornell put the cost @ ~40 tonne under favourable conditions if I recall correctly (using existing tech). Are you aware of any new studies that compare the cost of chemical air capture (ala David Keith) with this kind of bioligical capture?
@Marlowe: I don't think either the long-term storage capacity of biochar or the rate of biochar production is large enough to make a significant contribution. See, for instance, the 2009 Royal Society assessment of geoengineering at pp. 10-13 and the table on p. 20: The conclusion of this review is that biochar would have the capacity to reduce atmospheric CO2 concentrations by only 10-50 ppm.
Thanks for the link Jonathan. Needless to say I'm a little more bullish on biochar's prospects than the authors of the Royal Assessment are. More recent estimates put the mitigation potential of biochar, when constrained by sustainability criteria, at 12% of current emissions. IMO that's nothing to sneeze at.
To be clear, I'm not saying that we shouldn't support the work of David Keith --he's a Canadian after all :). As Roger is fond of saying, we shouldn't take options off the table. On the other hand, I think that there does need to be some recognition of the importannce of staging and costs.
Right now (and for the forseeable future) biochar is a much cheaper form of air capture than chemical routes and it provides far more co-benefits (i.e. increased soil fertility, energy co-products).
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