Billions of metric tons of carbon dioxide are stored in the Earth’s rocks, but some climate change advocates want to add more. A lot more.
Carbon storage via underground injection wells has been operational for decades, but supporters of carbon sequestration also want to store CO2 in cement via pulverized rock.
Through the heating and bonding of carbon dioxide (CO2) with powdered limestone, companies hope to “permanently and safely” store the trapped gas underground or within building materials like concrete.
One of these proposals is a Bill Gates-backed project. The California-based startup Heirloom, which aims to trap carbon in cement, is funded in part by Mr. Gates’ Breakthrough Energy Ventures.
On its website, Heirloom states that with global construction expected to double by 2060—what they refer to as building another New York City every month—the company says there’s an opportunity to store “immense quantities of carbon dioxide in our built environment.”
A long-time financier of carbon capture endeavors, Mr. Gates’ sponsored projects have sparked much debate within the scientific community. The Microsoft co-founder has already thrown more than $80 million at start-ups within the rapidly growing industry of CO2 sequestration.
Carbon capture and storage is booming due to increased pressure on businesses to reduce emissions.
One report noted that 67 percent of “experts” across 66 countries think companies must become carbon neutral by 2030 to stay competitive. The same analysis showed 32 percent believe the target goal should be 2025.
Consumer trends have also put companies in the hot seat over carbon-friendly practices. A 2022 study showed that from a group of more than 1,000 U.S. adults, 66 percent were willing to pay more for “sustainable” or carbon-friendly products.
The current market for CO2 capture and storage surpassed $6 billion last year and hit $12 billion in 2023.
As with some researchers, Mr. Gates criticizes the notion that trees and other plants could make enough of a dent in CO2 emissions to matter. However, some within the pro-plant community say putting more green in the ground will do more good than locking carbon in rocks alone.
Human-engineered carbon storage methods can also be hazardous and have resulted in significant human harm, even death. Environmentalists worry the consequences on natural ecosystems could outweigh the benefits in the long run.
“While the emergence of carbon capture technology to draw down legacy carbon dioxide from the atmosphere is promising, this technology is largely still in its infancy and should not be the only carbon capture solution we rely on,” Josh Knauer told The Epoch Times.
Mr. Knauer is the co-founder of ReSeed Carbon Assets, which focuses on incentivizing farmers to use regenerative farming methods. He says mechanical carbon capture is “enormously expensive” and is yet to prove its ability to scale as an industry.
However, putting plants in the ground is a proven method of trapping carbon. Mr. Knauer said this is particularly true if those working in agriculture—one of the most targeted sectors for excess carbon emissions—adopt methods advocated by ReSeed, including the use of cover crops, agroforestry, crop diversification, and rotational grazing.
According to Mr. Knauer, if farmers put more plants and trees in the ground, it could facilitate the climate community’s lofty goal of sequestering 1.2 billion metric tons of CO2 per year by 2050.
Mr. Knauer said this isn’t some abstract goal requiring pipelines, factories, or gimmicks. The existing 500 million smallholder producers in emerging countries, who own roughly 7.4 acres on average, can accomplish this by implementing ReSeed’s methods.
“This solution for carbon removal has been used for millennia: Good old-fashioned photosynthesis,” Mr. Knauer said. “Regenerative farming is a series of practices that improve the health of the soil and the entire farm ecosystem. It differs from traditional agriculture in that it seeks to work with nature rather than against it.”
He says that in order to draw down and store gigatons of atmospheric carbon, restoration and balancing natural ecosystems is critical, adding it’s the only “proven and scalable way” to achieve this.
What Lies Beneath
Supporters of expanding carbon injection well usage argue that CO2 capture in subsurface rock has occurred naturally for centuries. Yet the amount of carbon being transferred below American soil has triggered alarm because of the lethality of CO2 in high concentrations.
With 169 new carbon injection well permits currently under review, the United States is about to have much more CO2 transferred and stored beneath civilian populations. The CO2 injection wells can be at least a mile deep underground.
The U.S. Environmental Protection Agency (EPA) designates these types of underground carbon storage facilities as Class VI injection wells. However, there are risks associated with those wells, according to the litigation group Earth Justice.
“Burying carbon underground doesn’t make its environmental impact go away. The risks from injecting it include earthquakes, drinking water contamination, and releases of concentrated CO2 that can send people to the hospital,” the group states on its website.
Some researchers say carbon injection wells are bound to leak, because many already have.
Using historical data, one analysis posted on the International Council on Clean Transportation website estimates an average 7.5 percent of wells could experience “continuous leakage.”
That may not sound like much, but it amounts to 150 metric tons of CO2 leaking from active wells and another 300 metric tons of leaked CO2 for abandoned wells annually.
The same report maintains that leakage via abandoned wells is higher since they usually don’t have “frequent monitoring systems” in place, resulting in the likelihood of longer response and mitigation times.
Hazardous, even deadly, effects from CO2 leakage on human populations aren’t hypothetical scenarios.
In 2020, Satartia, Mississippi, suffered the effects of a critical CO2 pipeline rupture about half a mile away. Of the 300 people forced to evacuate the dangerous leak, 49 ended up in the hospital, according to the Climate Investigations Center.
An investigation showed the pipeline that failed was “relatively new” and erupted without warning.
The three men who initially spotted a “white cloud” of CO2 gas shooting up from the ruptured pipeline while on a fishing trip barely made it to their car before losing consciousness from CO2 poisoning.
Another harrowing incident occurred in 1975, when an “experiential injection well” suffered a catastrophic leak near Denver City, Texas, according to an old newspaper clipping from the Odessa American.
Nine people died while fleeing a cloud of mixed CO2 and hydrogen sulfide gas. Eight of the victims, two of whom were children, were fleeing toward the family’s car when they collapsed, overwhelmed by the lethal gas cloud.
The compromised Denver City well had been using gas instead of water to help recover more oil from an extraction site. Since then, CO2 has been used regularly by the fossil fuel industry for a type of extraction known as “enhanced oil recovery.”
The EPA currently regulates and permits Class VI carbon injection wells, but there’s increasing pressure from private industries—mostly fossil fuel-related—to hand over well permits to state authorities to speed up the process.
In March, S&P Global Commodity Insights observed a “backlog of applications” for carbon injection wells, prompting a group of state chambers of commerce and industry associations to send a frustrated letter to EPA administrator Michael Regan over “uncertain permitting timelines for Class VI injection wells.”
As it stands, the United States has the largest number of operational CO2 pipelines in the world, which transport 70 million tons annually, according to the Global CCS Institute.
President Joe Biden supports expanding subsurface carbon capture and storage and announced a $251 million spending package this year for both.
Opponents to increased underground CO2 storage say America isn’t ready and the danger is real.
“We’re looking at those pipelines being a lot closer to people and communities than they are right now,” Bill Caram, executive director for Pipeline Safety Trust said.
Then, there’s contaminated drinking water to consider. It has already happened with other classes of injection wells.
One analysis cited multiple injection well failures near Miami, Florida, where a test showed 10 out of 17 observed wells weren’t constructed property, resulting in leakage.
The study noted that “hazardous material” was found in drinking water, and further EPA study was needed.
Another case took place in Romulus, Michigan, where after just 10 months of operation, an injection well began to falter. It narrowly avoided contaminating the town’s water supply.
One of two scenarios could apply specifically to Class VI CO2 injection wells. The first is when CO2 “migrates” up the well bore and into an aquifer.
The second instance is if internal pressure forces brine from the injection zone directly into the underground water source.
The results are the same: poisoned water without a clearly defined mitigation process.
Even within the “green solutions” and energy transition community, there’s debate over what carbon capture methods hold merit.
“In my view, underground CO2 storage does pose risks to deep water reservoirs and shallow groundwater aquifers. However, mitigation strategies like careful site selection, monitoring, and the use of impermeable cap rocks can help address these challenges,” Christopher Jackson, CTO of the sustainable transportation solutions company Eco Motion Central, told The Epoch Times.
Written in Cement
The idea of trapping CO2 in cement isn’t a new one, but it’s gaining momentum.
Mr. Jackson called this “paradoxical” due to the heavy carbon-emitting nature of global cement production. Making cement accounts for more CO2 output than the entire aviation industry, comprising 8 percent of the world’s total carbon dioxide emissions.
The demand for cement for buildings is also expected to increase 48 percent by 2050, according to authors of a Rocky Mountain Institute article.
Like many, Mr. Jackson believes more research is needed before determining whether carbon capture in cement is realistic.
“The idea of storing CO2 in cement is indeed paradoxical. However, if the cement industry could significantly reduce its emissions, this could become a more viable solution. It’s all about balancing the scales,” he said.
“The use of pulverized limestone to boost carbon sequestration in soil is an interesting concept. However, it’s crucial to consider the potential impacts.”
Mr. Jackson underscored the core of the opposition argument, which is the same as with carbon injection wells: It’s more of a leap first and worry about the landing later approach.
Because when it comes to trapping carbon, he said a thorough lifecycle analysis must be considered before determining any net gain on sequestered emissions. This means an assessment of how much carbon is being emitted during the process of capturing and storing CO2.
For the moment, there’s a notable lack of this within the carbon sequestration industry.
In 2021, Cambridge University materials scientist Darshil Shah said he was among those “very concerned” about sending the wrong message regarding the cement industry’s ability to capture and store carbon.
It’s easy to get the math wrong regarding a carbon lifecycle analysis.
Mr. Shah referred to a report by the UN’s Intergovernmental Panel on Climate Change (IPCC) that concluded roughly half of CO2 emissions from cement production were reabsorbed by concrete buildings. However, he added those emissions account for “only a fraction” of the total produced by the cement industry.
He also admitted to being “a bit frustrated” with the IPCC report as using climate change buzzwords can give a misleading impression of the overall benefits.
On its best day, the climate change community remains divided over measuring the value of mechanical carbon sequestration. Most believe it will take a combination of well-researched approaches with clearly defined, provable results.
“Collaboration between industry stakeholders, governments, and researchers is crucial to transition towards greener cement production. Ultimately, a multi-faceted approach is essential to mitigate the industry’s substantial carbon footprint,” Robert Oates, managing director of the biodiversity and ecological survey company Arbtech, told The Epoch Times.
And while others debate, Mr. Knauer is focused on action and continues incentivizing farmers to put more plants in the ground.
“Regenerative farms around the world are already capturing carbon, drawing down carbon from the atmosphere, and returning it to the soil,” he said.