The company has been running a pilot plant since 2015, and is now in the market to raise $60-million as it prepares to build its first commercial-scale operation. But such technology is expensive-about $600 per ton of CO2, by one recent estimate.
He compared the idea of recycling atmospheric carbon into fuel to the idea of converting all the cars in the world, estimated at more than 1 billion, to electric and fueling them with electricity from renewable sources, which he said would be incredibly costly and disruptive.
"This isn't a PowerPoint presentation", said Steve Oldham of Carbon Engineering.
Those numbers are "real progress", says Chris Field, a climate scientist at Stanford University in Palo Alto, California. They are using direct air capture.
She has been involved in a project in Iceland where Carbon dioxide from direct air capture is being turned into rock, deep underground.
"What we've done is build a (direct-air capture) process that is-as much as possible-built on existing processes and technologies that are widespread in the world", Keith told The Atlantic. His process, though, could provide the means to adapt to climate change for activities that are hard to do without producing Carbon dioxide emissions, such as jet travel and producing concrete. But in 2011, a review panel of the American Physical Society found that DAC would likely cost about $600 per ton of captured CO2.
Other experts welcomed the study as a step to clear up huge uncertainties about the costs of "direct air capture". After capturing the Carbon dioxide in solution, the plant transfers it into a solid, which when heated releases it in a pure gas stream. After 3 years, Keith and his colleagues had collected enough data to calculate the plant's efficiency-and project the costs of building a commercial scale plant with the same technology.
A facility for capturing Carbon dioxide from air of Swiss Climeworks AG is placed on the roof of a waste incinerating plant in Hinwil, Switzerland July 18, 2017. Carbon Engineering says it can do the job for between $94 U.S. and $232 United States a tonne because it uses technology and components that are well understood and commercially available.
The study implies that falling costs of solar power could produce hydrogen affordably from electrolysis without producing an excessive increase in CO2. 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.
"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-priced 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. Such fuels are more expensive than standard gasoline and diesel, so the size and stability of the market for them will depend largely on whether subsidies are in place.
The fuel can now be produced at a cost that would not raise the prices to consumers at the pump, he said, and "as with anything, if you build lots of something the cost will come down".
Mr. Oldham said the air-to-fuel process could reduce the need to electrify the transportation system by providing a carbon-neutral alternative to traditional fuels. "There is a long way to go to see whether it will have any large-scale impact".