Carbon capture: Tech conference looks at latest innovation
Jackson – In mid-September, Wyoming Governor Matt Mead hosted leaders from around the world at the Wyoming Global Tech Summit to talk about technology in many aspects of science today, ranging from information security to medicine.
Among the speakers was Klaus Lackner, director of the Center for Negative Carbon Emissions at Arizona State University, who looked at carbon recapture and the potential for the future.
“If we think of it like a bank account, we have to figure out how to literally balance the carbon budget, so I started working on how to put carbon dioxide away,” Lackner said. “If we think of having a carbon credit card on which we are drawing, we’re already on overdraft, or we will soon be on overdraft.”
Carbon excess
Lackner said that, whether people believe in climate change or not, carbon dioxide (CO2) is building up in the global atmosphere.
“CO2 literally builds up in the atmosphere like garbage,” he described, noting that some of the CO2 is reabsorbed back into the ocean, but the majority of it persists in the atmosphere for hundreds of years. “As we put CO2 into the atmosphere, we have to get at least half of it back. But in the end, carbon dioxide also produces a disposal problem.”
Currently, the atmosphere consists of approximately 400 parts per million (ppm) of CO2.
He added that most climate scientists agree that CO2 in the atmosphere increases by two to 2.5 ppm per year.
“Currently, we put 36 billion tons of CO2 back into the atmosphere, and 15 billion tons adds a part per million,” Lackner said. “Climate scientists will also tell us that when we hit 450 ppm, the planet will also warm by two degrees Celsius.”
To decrease the rate of CO2 being released into the atmosphere, Lackner said that the U.S. must recapture more carbon than we release into the atmosphere.
“Every person uses 30 tons of carbon in their lifetime,” he said. “It’s time to balance the carbon budget.”
Negative emissions
In balancing the carbon budget, Lackner noted that the Intergovernmental Panel on Climate Change (IPCC) touted negative emissions at their recent meetings.
“We have to put back more than we put out because we are in an overdraft situation,” he explained. “We have to make sure we don’t overrun the 450 ppm, and there’s not question we will at this rate.”
If the globe maintains its level of carbon use, before the end of the century, the atmosphere is predicted to hit 800 ppm CO2.
“If we reduce emissions by 10 percent, we have pushed the problem into the future,” Lackner said. “If we got to 30 percent of current emissions, we will push the problem into the distant future, and that’s good for right now.”
Challenges
Lackner sees huge potential in capturing CO2 from the air to remove carbon from the atmosphere.
“The technology of air capture is technologically and conceptually very simple,” he said. “I have a device that we blow air through, and it takes the CO2 out.”
At the same time, he added that air capture has the potential to actually reduce the amount of carbon in the atmosphere below it’s current level, beyond only compensating for future output.
Secondly, Lackner sees potential in completing the carbon cycle by utilizing captured CO2 and hydrogen to make gasoline, methanol, dimethyl ether and more.
“We can make plastic. We can make carbon fiber, and we can use them,” he said. “I can create a circular carbon economy without ever touching fossil fuels.”
Finally, he noted that those using fossil fuels are responsible for returning the carbon removed from the ground from the atmosphere.
“Over the next 20 or 30 years, I think we’ll see regulatory frameworks where dumping CO2 into the atmosphere is outlawed,” Lackner commented.
Air capture
Two things make carbon capture from air challenging – the fact that CO2 in air is “tight” and there is a lot of water in air.
“There is far more water vapor in air than CO2, and the problem is, anything that binds CO2 loves water,” Lackner explained. “We have to figure out how to get around that problem.”
Additionally, the technology is currently very possible, though he likens the argument against air capture because of the expense to arguments made by locomotive engineers against flight made at the turn of the century.
“It’s not physical law that says air capture of carbon is impossible, it’s a lot of work,” he said. “It’s feasible to do air capture.”
At the same time, Lackner noted that the technology is expensive now, but all renewable technologies were initially very expensive.
Currently, estimates with other processes are that capture costs $600 per ton to capture CO2 from the air.
“I think it can cost, practically, $100 per ton, to do air capture,” he said.
He added, “Photovoltaic panel costs dropped 100-fold from 1960 to today. Wind plants have dropped in price 40-fold. We can see that cost will decrease.”
New technology
Lackner noted that the CO2 content of air is quite small.
“There is a liter of CO2, or about two cups, in every cubic meter in air,” he said.
They have figured out how to capture CO2 from the air passively, only utilizing wind and natural air movement to capture CO2.
“We use an anion exchange resin, which has the remarkable feature that, when it’s dry, it loves CO2,” he said. “When it’s wet, it gives it back.”
Lackner continued, “We load up the resin, and by the time we reach 40 kilo-Pascal, which is full. Then, we make it wet, either by exposing it to 100 percent relative humidity or spraying water on it.”
Then, the resin is dried and can be reused.
“We need to figure out how to utilize this best,” he said. “It is extremely powerful, and mass production will get us there.”
He further added that he estimated three years before the technology is ready to be readily disseminated.
“As we fast forward, we need to convince the public that CO2 disposal is also necessary,” Lackner said, noting that there is a challenge in disposing of captured carbon. “Negative emissions is going to be a huge, huge business opportunity in the future, and I’m pretty sure air capture technologies will be a part of that future.”
Saige Albert is managing editor of the Wyoming Livestock Roundup and can be reached at saige@wylr.net.
