Assume for the purposes of discussion that catastrophic global warming from human CO2 emissions can be reliably predicted. Here’s a thought: since we know trees sequester carbon (but couldn’t be planted on a scale large enough to mitigate 30 billion tons of annual CO2 emissions), why not go one step further and investigate whether there might be technologies that would remove carbon dioxide from the air? The idea is called “air capture,” but whenever the idea is brought up, you can hear the crickets chirping among the climatistas, for whom nothing less than destroying hydrocarbon energy will suffice as atonement for humanity’s sins of emission. (Near as I can tell, the IPCC completely ignores the idea.)
Maybe the idea is starting to get a little more attention. BigThink.com reported recently on a pilot project:
In the beginning of this year, in Squamish, British Columbia, the privately owned (and backed by Bill Gates) company Carbon Engineering began the construction of the first air-capture CO2 demo plant. For years, the company has been developing the technology that is now ready to be implemented on a larger scale.
Like trees, air-capture technology traps CO2 from the ambient air. However, as the team at Carbon Engineering points out, “planting enough trees in the numbers needed would require diverting vast amounts of agriculturally productive land. In fact, to absorb enough CO2 as an air-capture facility, trees would require roughly a thousand times more land.” Unlike trees, however, air-capture plants can be built on land that cannot be cultivated, such as deserts.
If you read the whole thing (or watch this seven-minute video), several essential elements are missing: Can it be scaled up? How much energy does this technology require to work? Unless it comes from nuclear power or some other carbon-free source, it is not clear that the net reduction of carbon would be positive. And the big one, of course, is how much would it cost per ton of emissions reduction? It always amazes me that reporters never think to ask these questions. (The best part of the Carbon Engineering story, if it pans out, is converting CO2 back into fuel.)
Nature magazine reported on the Carbon Engineering project last week along with a similar effort by Climeworks, a Swiss company, that does somewhat better:
In 2011, a report from the American Physical Society (APS) estimated that air capture would cost at least US$600 per tonne of CO2, assuming a large system that removed 1 million tonnes of CO2 per year. But Climeworks says that its price will be in that range in the first year of its plant’s operation, despite being on a smaller scale than the APS example. The company also expects that cost to fall as the technology develops. Keith, meanwhile, says that the CO2 produced by Carbon Engineering’s plant is expensive, but emphasizes that it is a pilot; he says that prices of $100–200 per tonne of CO2 are realistic for the bigger iterations that it is planning.
That’s still a rather high cost, but it is noteworthy to see the work going forward. Because—and this is the main point—if air capture becomes scalable and affordable, you can be certain that the climatistas will be dead set against it.