A novel way to reduce carbon dioxide deposits in the atmosphere is in the works and found to be cheaper than previously thought.
Direct air capture exists since the 1940s, but scientists said it is an extremely expensive means to remove carbon dioxide in the air.
Direct Air Capture
Direct air capture costs $1,000 per metric ton of carbon dioxide based on a 2011 estimate. David Keith, a professor at the Harvard John A. Paulson School of Engineering and Applied Sciences, said it is possible without costing a fortune.
In a study published June 7 in Joule, Keith's team proposed a new way to reduce the cost of the siphoning technology between $94 and $232 per metric ton of carbon dioxide.
"We're making something that's never been done before — commercial large-scale air capture — but we're doing it on a basis of technology that already exists," said Keith.
Experts believe that the paper could have major effects in the bioengineering industry.
The Siphoning Process
Keith and his colleagues' company, Carbon Engineering, supplies the technology needed to conduct this process. Carbon dioxide molecules make up only 0.04 percent of air, but an effective strategy has to be in place to remove 200 years' worth of fuel gas in the atmosphere.
In Carbon Engineering's approach, an array of industrial-sized cooling tower uses a solution of liquid hydroxide to capture and convert carbon dioxide into carbonate. The carbonate is then transformed into pellets using a machine that extracts the water minerals. Lastly, the carbon pellets are then "roasted" before it can be used to manufacture synthetic fuel
Transforming The Industry
Keith said their study is the first to estimate the cost of direct air capture. He added that it gives companies the confidence to transform the technology into an industrial scale.
"As with any industrial technology, there is a sharp distinction between the ease of developing 'paper' designs and the difficulty of developing an operating plant," the authors wrote. "CE has now spent roughly 100 person-years on such apparently trivial items to develop a process proposed almost two decades ago by Klaus Lackner and collaborators."
Joseph Lassiter, Senator John Heinz Professor of Management Practice in Environmental Management at Harvard Business School, said carbon removal facilities like this can be placed anywhere where the cost of renewable energy is lower.
Keith's team has raised $30 million. They are also on the lookout for a possible renewable energy supplier who can provide lower prices.