San Antonio company captures CO2, but one expert says it does more harm than good
Martin Keighley said he joined CarbonFree as its CEO four years ago because he wanted to be part of the solution to climate change — and make money while doing it.
“We have a big problem out there in terms of the need to address climate change, the CO2 in the atmosphere,” Keighley said. “But we see it as a big opportunity. And for us, it’s an opportunity to run a profitable business.”
Keighley and San Antonio-based CarbonFree have an ambitious goal: to capture 10% of all industrial emissions of carbon dioxide by 2050 Those industrial CO2 emissions account for roughly one fifth of all global emissions.
Carbon capture is one of several technologies being considered as major ways to reduce carbon dioxide emissions as the planet continues to warm to increasingly dangerous levels.
In fact, the federal government has committed hundreds of billions of dollars in the last several years to support the young industry with tax credits and infrastructure.
The basic idea behind carbon capture is simple: fossil fuel and industrial plants produce much of the CO2 emissions in the atmosphere, so what if those emissions were caught before they could get to the atmosphere?
Companies typically capture carbon from flue chimneys, the smokestacks coming out of fossil fuel and industrial plants. Once a company captures carbon, there are two basic things it can do with it.
“We talk about CCU and CCS,” Keighley said. “Carbon capture utilization and carbon capture storage.”
CCU is a process where companies use captured CO2 to make chemical products. CCS, also known as carbon capture sequestration, is a process where companies take captured CO2 and store it away, typically underground.
CarbonFree currently operates one carbon capture plant, called SkyMine, next door to a San Antonio cement factory. That plant runs on the CCU model, where it captures some of the cement plant’s emissions and uses a chemical process to turn them into several products.
“We make baking soda, we make hydrochloric acid, caustic, and bleach,” Keighley said.
Keighley acknowledged that baking soda, SkyMine’s primary product, decomposes over a relatively short period and ends up re-emitting much of the carbon stored in it.
But he said a forthcoming CarbonFree facility called SkyCycle will produce a product that can store carbon for centuries or millennia — precipitated calcium carbonate, or PCC. PCC is used as a filler in numerous products.
“It goes into things like … paper, paints, emulsions, into detergents,” Keighley said. “It also goes into food products like toothpaste.”
The SkyCycle plant will capture carbon from an Indiana US Steel plant. It will operate as a CCUS plant because it will both utilize and store carbon through PCC. To Keighley and many others, carbon capture is a win-win for the environment and their bottom line.
Stanford Civil and Environmental Engineering professor Mark Jacobson is one of carbon capture’s biggest critics. He said doing nothing would be better than supporting the technology.
“Carbon capture is a scheme of the fossil fuel industry,” Jacobson said. “I mean, they go hand-in-hand. It’s just a way for the fossil fuel industry to extend themselves.”
Jacobson is a strong proponent of a full and immediate transition from fossil fuels to renewable energy.
He published a book earlier this year titled No Miracles Needed, in which he argued that we already have all the technology we need to solve the climate crisis — solar, wind, and water power generation — without so-called “miracle technologies” like carbon capture.
He said he believes technologies like carbon capture are tools the fossil fuel industry can use to keep their plants running with promises of reduced emissions. Oil giant BP has been a long-time investor in CarbonFree, though Keighley said the fossil fuel company is only a small investor.
Jacobson added that carbon capture companies rarely live up to big claims about emissions reductions.
“The full load capture rate under ideal conditions can be like 90%,” he said. “However, in reality, the actual projects are between 20 and 70%.”
The full load capture rate is what carbon capture companies estimate as the absolute best their plants could do in the best circumstances, which are often unavailable.
At SkyMine, CarbonFree boasts that it has the capacity to capture 50,000 tons of CO2 per year, or 15%-20% of the plant’s emissions. But since it’s been operational, it hasn’t surpassed more than 20,000 tons per year.
Keighley said SkyMine represents a stepping stone to bigger and more efficient projects like SkyCycle.
“It’s not a pilot plant, but it also demonstrates the technology to someone like US Steel, and then working with them on the next stage of growth up to something more like half a million ton capture,” he said.
SkyCycle is only expected to capture 15%-20% of the US Steel plant emissions in its first few years of operations, but Keighley again said it’s a way to prove the technology works and get it ready for larger scale capture.
Keighley added that capturing carbon is good, even if it’s not as much as they hoped. But Jacobson disagreed.
“You have to do something with the carbon dioxide,” Jacobson said. “Well 75% of all CO2 is used for enhanced oil recovery. And that process alone puts 40% of the CO2 right back to the air.”
Both SkyMine and SkyCyle have hydrochloric acid as a byproduct, and Keighley acknowledged that some of that is sold to fossil fuel companies for use in oil extraction. But he said it isn’t a big part of their business.
“Our preference by far is to sell that [hydrochloric acid] into industrial markets, not particularly the oil and gas [industry],” Keighley said.
Though Keighley said SkyCycle will be a carbon negative facility, Jacobson said many carbon capture plants end up producing more carbon through their construction and operation than they will ever capture.
He also pointed to the fact that many carbon capture plants run on fossil fuel themselves. But he said even if they ran off of renewable energy, it would just be better to skip the carbon capture middle man and replace whatever CO2-emitting plant they’re capturing carbon from with renewable power.
Even for hard-to-abate industrial emissions, which is the focus of CarbonFree, Jacobson said carbon capture is still not useful. He said Sweden uses a 100% renewable process to produce its steel and that there are ways to make geopolymer cement with renewable power.
“It’s better to replace fossil fuel plants with renewable electricity,” Jacobson said. “These are all just greenwashing schemes. Sure companies can make money off of it, but it’s not useful for the environment.”
But Kieghley pushed back.
“I believe very strongly that we need to work with current industrial emitters to manage their emissions as they are … otherwise you are decades away from getting real uptake on new technologies,” Keighley said.
Though carbon capture might be one solution to the climate crisis, a 2022 report from the International Energy Agency found that the industry’s current impact is dwarfed nearly 5 to 1 by what would actually be required to hit net-zero emission goals by 2050.