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technology, criticized the American Physical Society study as too narrowly focused, saying it had analyzed only outdated technology.I very much agree with this last sentiment, as I explain in detail in The Climate Fix which has a lengthy discussion of air capture (which has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.
