Removing C02 from the Atmosphere — Most Efficient Process Yet Found

With climate change’s dangers looming, it would be sensible for more people to try to lower the cost of direct air capture demonstrated here. Estimating that humans put 50 billion tons of C02 in the atmosphere every year, with the cost of removing one ton of C02 being at maybe $100, it would cost approximately $5 trillion (5-6% of world GDP) a year to offset the new C02 being added yearly. It isn’t clear to me how much value would be able to be generated by the tons of C02 captured, but I am aware that there are good catalysts for recycling C02 into valuable chemicals available.

Even so, it’s troubling that governments around the world don’t join forces to reduce the costs of this direct air capture and contribute money towards using it more. Eventually, my guess is that something similar to this technology is going to have be used much, more in the future. I don’t think humanity is moving fast enough to ditch fossil fuels for clean energy, and the next ten years are going to be especially crucial in what happens with climate change. The problem with C02 removal is going to continue to revolve around the high cost to do it though — if the cost could be further lowered significantly, much of the warming this century could be prevented.

By removing emitted carbon dioxide from the atmosphere and turning it into fresh fuels, engineers at a Canadian firm have demonstrated a scalable and cost-effective way to make deep cuts in the carbon footprint of transportation with minimal disruption to existing vehicles. Their work appears June 7 in the journal Joule.

“The carbon dioxide generated via direct air capture can be combined with sequestration for carbon removal, or it can enable the production of carbon-neutral hydrocarbons, which is a way to take low-cost carbon-free power sources like solar or wind and channel them into fuels that can be used to decarbonize the transportation sector,” says lead author David Keith, founder and chief scientist of Carbon Engineering, a Canadian CO2-capture and clean fuels enterprise, and a professor of applied physics and public policy at Harvard University.

Direct air capture technology works almost exactly like it sounds. Giant fans draw ambient air into contact with an aqueous solution that picks out and traps carbon dioxide. Through heating and a handful of familiar chemical reactions, that same carbon dioxide is re-extracted and ready for further use — as a carbon source for making valuable chemicals like fuels, or for storage via a sequestration strategy of choice. It’s not just theory — Carbon Engineering’s facility in British Columbia is already achieving both CO2capture and fuel generation.

The idea of direct air capture is hardly new, but the successful implementation of a scalable and cost-effective working pilot plant is. After conducting a full process analysis and crunching the numbers, Keith and his colleagues claim that realizing direct air capture on an impactful scale will cost roughly $94-$232 per ton of carbon dioxide captured, which is on the low end of estimates that have ranged up to $1,000 per ton in theoretical analyses.


Centuries of unchecked human carbon emissions also mean that atmospheric carbon dioxide is a virtually unlimited feedstock for transformation into new fuels. “We are not going to run out of air anytime soon,” adds Steve Oldham, CEO of Carbon Engineering. “We can keep collecting carbon dioxide with direct air capture, keep adding hydrogen generation and fuel synthesis, and keep reducing emissions through this AIR TO FUELSTM pathway.”


“After 100 person-years of practical engineering and cost analysis, we can confidently say that while air capture is not some magical cheap solution, it is a viable and buildable technology for producing carbon-neutral fuels in the immediate future and for removing carbon in the long run,” says Keith.