Monte Markley, a geologist who lives on a farm near Wichita, Kansas, describes his job as “putting things underground and keeping them there.” As an environmental consultant, he specializes in disposing of industrial waste in subterranean rock formations. “All through my career, I’ve helped industries deal with the things that come out of the back side of a plant that nobody wants to talk about,” he told me. In early 2020, he got a call from Shaun Kinetic, a co-founder of a Bay Area company called Charm Industrial. Kinetic, who has experience building robots, satellites, and rockets, wanted to know how to dispose of a particularly troubling kind of waste: the excess carbon that contributes to global warming.
Markley had worked with companies that were trying to capture and store their own carbon emissions before they entered the atmosphere. But Charm was working with carbon that was already in circulation. The company was adapting a machine called a pyrolyzer, which heats plant material such as cornstalks in an oxygen-free environment, so that the plants turned into bio-oil, a carbon-rich liquid with the color and consistency of dark maple syrup. Kinetic wanted to know whether it was feasible to dispose of bio-oil underground. Markley said that it was—in fact, bio-oil would likely remain trapped there for centuries, if not longer. The process would resemble the drilling and burning of conventional oil, but in reverse.
In late 2021, Kinetic called again. Charm’s team hoped that, eventually, mobile pyrolyzers would allow the company to produce bio-oil on farms. To that end, Kinetic asked, could Charm Industrial test the latest version of its pyrolyzer on Markley’s land? Markley talked it over with his wife, Anna. Together, they had restored the acres they now farm, and both had a long-standing interest in conservation; the search for climate solutions appealed to them. Markley remembers thinking, “Wouldn’t it be cool to be able to tell our kids what we were a part of?” The couple signed an agreement to lease land to the company.
In January, 2022, a procession of semitrailers delivered three large shipping containers to the Markleys’ farm. Kinetic and his wife, Kelly, another Charm co-founder and the company’s chief technical officer, arrived in their Kia three days later, having been delayed by a blizzard. Charm’s engineers unpacked the pyrolyzer a few hundred yards from the Markleys’ house; they had nicknamed the device the Apatosaurus, after the long-necked, herbivorous dinosaur. Markley was delighted by its gangly complexity. “It looked like something that would show up on Elon Musk’s Twitter,” he told me.
Then came the realities of a Midwestern winter. Snow piled up on the container that housed the pyrolyzer. Freezing temperatures stalled the machine’s LCD screens. The pyrolyzer was designed to process ten metric tons of biomass per day, but cornstalks from nearby farms contained rocks and other debris that had to be filtered out. The machine often hummed until two in the morning. “My wife would be, like, ‘What have you done?!’ ” Markley recalled. The couple sometimes invited the tinkerers in for coffee or dinner. After six months, the number of tons of bio-oil that the Charm team had produced was in the single digits. The pyrolyzer worked, but nowhere near as well as it needed to.
The best way to stave off catastrophic climate change is to stop burning fossil fuels. Lately, though, the world’s leading climate scientists have warned that a gradual phase-out of oil, gas, and coal won’t be enough. If humanity is to keep the planet from warming more than 1.5 degrees Celsius, we will likely need to remove at least a gigaton of carbon, and possibly more than ten gigatons, from the atmosphere every year—and to stash it somewhere for centuries to come. (One gigaton is more than twice the combined weight of every person on the planet.) Critics of carbon removal have long feared that it will offer polluters an easy way out, by giving them an excuse to continue their emissions. The real problem may be that there is nothing easy about it.