What does that mean? Consider an example: If you were to burn Carbon Engineering’s gas in your car, you would release carbon-dioxide pollution out of your tailpipe and into Earth’s atmosphere. But as this carbon dioxide came from the air in the first place, these emissions would not introduce any new CO2 to the atmosphere. Nor would any new oil have to be mined to power your car.
Eventually, a similar process could be used to sequester greenhouse gases. Instead of converting carbon dioxide into a liquid fuel, Carbon Engineering could pump it deep into the ground, reducing the amount of heat-trapping gas in the atmosphere. But such a technique wouldn’t give Carbon Engineering any product to sell, and there are no buyers stepping up to front the effort, for now.
“The main, near-term market is making carbon-neutral hydrocarbon fuels,” Keith told me. “We see this as a technology for decarbonizing transportation.”
Speaking from Cambridge, Massachusetts, on Wednesday, Keith said he was “pretty optimistic” about climate change. “The reason is that the market for these low-carbon fuels is much, much better than they were a few years ago. At the same time, low-carbon power—electricity generated by solar and wind—has just gotten much cheaper.”
Outside experts said they were encouraged by Keith and his colleagues’ approach, but cautioned that it would take time to examine every cost estimate and engineering advance in the paper. The consensus response was something like: Hmm! I hope this works!
“I don’t question that the range of costs they report are valid. I think the lower end of $100 per ton of CO2 produced through their approach is probably doable in five years or so and that their higher end of $250 per [ton of] CO2 is more doable with their technology today,” says Jennifer Wilcox, an associate professor at the Colorado School of Mines.
“The improvements that Carbon Engineering have made all seem appropriate, and I am comfortable that their estimated costs are within the window of what I would expect from such improvements,” says Roger Aines, a senior scientist at Lawrence Livermore National Laboratory’s energy program.
“The strongest part of this paper, in my opinion, is the fact that they’ve actually tested the technology in a prototype plant for a few years. That’s a big deal, and offers a proof of principle that’s way stronger than simple calculations or computational models,” says Scott Hersey, an assistant professor of chemical engineering at Olin College.
Caldeira said that the paper offered hope for the trickiest parts of the economy to adapt to climate change. “This suggests that the hardest-to-decarbonize parts of the economy (e.g. steel, cement manufacture, long-distance air travel, etc.) might continue just as they are now, and we just pay for CO2 removal,” he told me.