Scientists want to help save the Earth by storing carbon dioxide in the ground

PALISADES, NEW YORK — Peter Kelemen spends time in Oman looking for ways to pull carbon out of the air and put it back underground. His colleague, David Goldberg, looks at ways to store it far below the sea floor off the Oregon coast. Chemical engineer Alissa Park is working with steel mills in China to turn slag and waste carbon dioxide into reusable material.

The goal of all three Columbia University researchers — and thousands of other scientists and engineers globally — is to find ways to pull some of the carbon dioxide that’s causing global warming out of the atmosphere and store it away. It’s called carbon capture and storage, and experts increasingly say it’s going to be essential to saving the planet.

Carbon capture and storage might sound like the plot of a crazy science-fiction movie, one where an intrepid band of risk-takers swoops in to save the Earth from certain destruction with engineering, grit and (in some scenarios) good old American know-how.

Except it’s no Hollywood film. Humanity is facing catastrophe as climate change causes the Earth to warm. Modeling by the Intergovernmental Panel on Climate Change suggests to keep it from wreaking climate havoc, we can add no more than 800 metric gigatons of carbon dioxide to the atmosphere by 2100. We’re adding 37 gigatons a year now, meaning that at this rate, we’ll have used up our entire carbon budget for the century in just under 22 years.

In the atmosphere, carbon dioxide acts like a blanket, keeping the heat in. The more of it there is, the hotter things get. Before the Industrial Revolution of the 1800s, carbon dioxide levels in Earth’s atmosphere were about 280 parts per million. Today, they’ve reached 410 ppm.

“People think that if the U.S. consumer just reduces her energy consumption that will solve the problem. But it won’t,” said Kelemen, a geochemistry professor at Columbia’s Lamont-Doherty Earth Observatory in Palisades, New York.

A piece of peridotite from Oman, a rock type that naturally absorbs carbon dioxide and mineralizes it, literally turning it into solid carbonate, similar to limestone or marble. The white lines in the rock are calcium carbonate formed by the mineralization process. Peter Kelemen, a geochemistry professor at Columbia’s Lamont-Doherty Earth Observatory in Palisades, New York, is studying how such rock formations could be used to store carbon for thousands of years, to help fight climate change.

A tax credit that could save the planet?

Carbon capture means just that, using industrial-strength scrubbers to grab carbon dioxide pollution as it’s emitted from the chimneys of power plants, steel mills, cement factories, ethanol distillers and other industries so it’s not spewed into the atmosphere. Or in some cases simply sucking it out of the air itself.

Making large-scale carbon capture and storage happen became a lot more likely a year ago in February when Congress passed potentially momentous legislation aimed at combating climate change.

Close to 20 years in the making and long fought for by a diverse coalition of environmental groups, oil and gas companies, industries and unions, the legislation turned an older tax credit for capturing and storing carbon into what could be a potent tool for fighting global warming.

Called 45Q in the tax code, it creates a tax credit of $35 for each ton of carbon dioxide stored permanently underground in oil and gas fields and a higher value credit of $50 for each ton of carbon dioxide stored in other geologic formations from which no oil is produced.

The government subsidy moves taking carbon dioxide out of energy and industrial processes from the “nice idea but generally impractical” side of the balance sheet to the “we could make money if we do this” side, said Brad Crabtree, vice president for carbon management at the Great Plains Institute, a nonprofit energy and policy organization in Bismarck, North Dakota.

“For the first time, it actually puts a price on carbon dioxide — it’s the first step of a design for a carbon market,” said Julio Friedmann, a senior researcher at Columbia University’s Center on Global Energy Policy and a former official at the U.S. Department of Energy during the Obama administration.

Just using carbon capture and storage at U.S. coal and natural gas power plants could remove 49 million metric tons of carbon dioxide from atmospheric release a year, an analysis by the Clean Air Task Force last month found. That’s two-thirds of the way to 2030 U.S. power sector goals from the International Energy Agency.

This is a technology the United States could be a global leader on, said Kurt Waltzer of the Clean Air Task Force, a Boston-based environmental group that focuses on pragmatic climate change solutions.

The U.S. is uniquely situated to capitalize on carbon capture and storage efforts because it has multiple industries that produce lots of carbon dioxide as waste, a large oil industry and, crucially, 4,000 miles of carbon dioxide pipeline to get it from one location to the other.

Carbon capture pipelines like this one in west Texas inject liquefied carbon dioxide gas, in this case obtained from natural gas processing plants, into oil-bearing rock layers to force out petroleum. Pipelines planned in Iowa and surrounding states would collect the gas from ethanol plants and other agricultural industrial facilities and permanently inject it into storage sites in North Dakota and Illinois.

This is where oil fields come into the picture. Right now, one of the major industrial uses of carbon dioxide is to inject it into played-out oil fields to get more of the fossil fuel out of the ground. Today, 23 million metric tons of carbon dioxide are captured annually from natural gas processing plants, refineries, and fertilizer plants and used for this process, known as enhanced oil recovery.

Critics, however, fear the carbon storage tax credit is a subsidy that will help prop up oil companies they want to shut down. Environmental group Greenpeace calls it a case of misplaced priorities.

“We need to think about what’s the most important way to spend our money and our political will,” which means shifting to renewables, not working on things that allow the fossil fuel industry to continue producing, said Janet Redman, the environmental group’s climate director.

Coming together to save the planet

It’s no secret that since the 1990s, climate policy debates in the United States have been characterized by deep political divisions between Republicans and Democrats, between the coasts and the heartland, and between fossil fuel and renewable energy. Carbon capture has brought them together.

The 45Q tax credit created some surprising bedfellows. Sen. Sheldon Whitehouse, a Democrat from Rhode Island, supported it because he worried about his state drowning. Sen. John Barrasso, a Republican from Wyoming, wanted a future for coal.

“You’ve got environmental organizations sitting right next to coal companies and labor unions — when does that happen?” said Lee Anderson, governmental affairs director for the Utility Workers Union of America, which is betting the carbon storage plan will protect jobs for its members.

Getting this all up and running at scale won’t be easy, but neither is it impossible. The two easiest methods of carbon capture and storage we already know how to do, but we’re not doing them enough.

Planting forests works, because trees take carbon dioxide out of the air and turn it into wood, which can store the carbon for hundreds and even thousands of years.

Relatively simple agricultural fixes also help. Planting cover crops like clover that are tilled into the soil, applying manure or compost, and using planting methods that disturb the ground less than plowing all result in more carbon being deposited into the soil.

Other ideas include fertilizing the oceans with iron to cause plankton and algae populations to bloom. They capture carbon and some sink to the seafloor when they die, effectively storing it away. Or taking mine tailings or rocks that naturally absorb carbon dioxide, and grinding them up to make larger surface areas so they do it more quickly.

But many believe two more technical types of capture and storage that could potentially make up the difference between land management carbon storage are what’s needed.

In the United States, the focus has been on removing carbon dioxide from power plant exhaust or industrial processes by using industrial “scrubbers” to separate it. The carbon dioxide can then be used for enhanced oil recovery, or simply pumped underground for long-term storage.

Another option is direct air capture and storage. This involves constructing huge fanlike machines to suck in air, pull out carbon dioxide via chemical processes and then store it underground. Pilot projects to do this are underway in Switzerland and Iceland.

The hope is that in the United States, the tax credit will make carbon capture and storage more affordable.

A Core Energy CO2 capture plant in northern Michigan. At this plant, carbon dioxide is captured from an adjacent natural gas processing plant and then transported via pipeline to Core Energy oilfields where it is used for enhanced oil recovery after it is dried and compressed after capture.

Take the case of Core Energy, an oil and natural gas company based in Traverse City, Michigan. It uses separation equipment, scrubbers and compression to remove carbon dioxide from its wells. But it only makes sense to turn them on when the price of oil is above $50 a barrel because they take energy to run, which makes the oil more expensive to produce.

In the past, when the price of oil dropped, “we just shut down the compressor that captured the CO2, so it gets vented into the atmosphere. With the tax credits we won’t be so quick to shut it down,” said Robert Mannes, president and CEO of Core Energy.

The credit was one reason behind a recent deal between Houston-based oil and natural gas producer Occidental Petroleum Corp. and Frisco, Texas-based ethanol production company White Energy. Occidental will use carbon dioxide captured from White Energy’s ethanol fuel production facility in Plainview, Texas, in its enhanced oil recovery operations.

Stopping the Earth from heating up

Carbon capture and storage is by no means the only solution to stopping climate change, a point everyone working in the field makes again and again. The primary focus should be speeding up the ongoing shift to carbon-neutral energy, they say.

But to keep Earth from heating up, humanity will need to use every tool in its toolbox.

“We have to do lots and lots and lots of things, a whole laundry list of things. You can’t just pick the ones you like and ignore the others; you’ve got to do them all,” said Anderson of the Utility Workers Union of America. 

David Goldberg, a marine geology professor at Columbia’s Lamont-Doherty Earth Observatory in Palisades, New York, with a piece of porous basalt. He’s proposed a test that would pump 10,000 metric tons of carbon dioxide 1,000 to 2,000 feet down below the ocean floor off the Pacific Northwest coast. Iceland already has a similar pilot project up and running.

At Columbia, multiple researchers are working on where we might store all this carbon dioxide in the future.

Goldberg, a marine geology professor, has mapped areas off the coast in the Pacific Northwest where porous basalt rocks could absorb it. He’s proposed a test that would pump 10,000 metric tons of carbon dioxide 1,000 to 2,000 feet down. Iceland already has a similar pilot project up and running.

Kelemen, the geochemistry professor, has been going to Oman for over 25 years to study its vast formations of peridotite, a stone that naturally absorbs carbon dioxide and mineralizes it, literally turning it into solid carbonate, similar to limestone or marble. He notes the same rock formations are also found in northern California and southern Oregon but that the will to explore storage there is politically problematic.

The message from the scientists is that mankind has the knowledge to put the carbon dioxide back where it came from and stop adding more — we just lack the political will to make it happen.

Starting with the technology we have today, “we could have an industrial carbon capture and storage solution in 50 years,” Goldberg said.