Etosha Cave slept in her car to save money and has since raised $900 million to make jet fuel from CO2

When Etosha Cave was growing up in Houston, Texas, there was an abandoned oil and gas site close to her home. Nobody seemed particularly worried about it, at least not the people who were supposed to be. But the teenager who would grow up to raise nearly a billion dollars in climate technology funding noticed what the adults were ignoring: leaking tanks, compromised water lines, contamination spreading slowly into the surrounding area, and a community that was not being told the truth about any of it.

"I grew up adjacent to an abandoned oil and gas site," she said. "My family was not directly affected, but I saw all of it taking shape when I was a teen. It got me very passionate about environmental waste and reusable energy."

That early anger did not make her a protestor. It made her an engineer.

From Houston to Antarctica

Cave's path from that Houston neighborhood to the cutting edge of climate science is not the straightforward kind that gets packaged neatly on a university admissions brochure. It is the kind that involves a summer spent alone in Antarctica, years of knocking on doors that did not open, and at least a few months of sleeping in a car.

In high school, she joined the National Society of Black Engineers and earned a scholarship that pointed her toward Franklin W. Olin College of Engineering in Needham, Massachusetts, where she was part of the first graduating class in 2006. Olin was unusual even by the standards of elite engineering schools: a small, intensely practical institution that trained students to actually build things rather than simply understand the theory behind them. Cave thrived.

After graduating, she took a job at McMurdo Station, the United States' main research facility in Antarctica, where she serviced HVAC systems and tested an open path laser diode spectrometer that would be used for a future NASA rover mission. The isolation of Antarctica turns out to be formative in ways that are difficult to anticipate. It was at McMurdo that her thinking about waste, pollution and transformation sharpened into something more specific than the environmental frustration she had carried since Houston. Watching the station's waste management systems transform materials that would otherwise become pollution into something useful confirmed for her that the problem she wanted to spend her career on was not advocacy. It was chemistry.

She came back from Antarctica knowing exactly what she wanted to do. She enrolled in a doctoral program at Stanford University under Professor Thomas F. Jaramillo, one of the world's leading experts in electrochemistry and catalysis. Her PhD, completed in 2015, focused on electrochemical approaches to converting carbon dioxide and water into useful plastics and household cleaners. Along the way, she built a gas analysis system capable of determining the composition of electrochemical reactions in real time. She had found her problem, and she had found the tool to address it.

Building Twelve

At Stanford, Cave worked alongside Kendra Kuhl, another doctoral researcher pursuing similar problems in Jaramillo's lab. The two scientists became convinced they had identified something with the potential to fundamentally alter how the world makes things. The insight was counterintuitive: carbon dioxide is not only a problem. It is a carbon source. And carbon is what the world manufactures almost everything from. Fossil fuels. Plastics. Chemicals. Jet fuel. What if you could make those same products from the carbon already sitting in the atmosphere, using water and electricity as additional inputs?

The science said yes. By using transition metal catalysts to drive electrochemical reactions in a proton exchange membrane reactor, they demonstrated that CO2 could be converted into any of 16 different organic molecules, including compounds that industry currently produces from petroleum at enormous scale. They teamed up with Nicholas Flanders, a Stanford graduate and clean tech entrepreneur, and co-founded Twelve in 2015, originally operating under the name Opus 12.

Then they tried to raise money in Silicon Valley. Silicon Valley told them no.

"At first, local venture capitalists weren't interested in funding a CO2-processing machine from scratch," Cave recalled. "They were busy chasing hot apps." The three founders were not building software that a venture capitalist could deploy at scale overnight. They were building hardware that required physical plants, specialised catalysts and industrial infrastructure. The pitch meetings were short. The doors closed quickly.

Cave's response was not to pivot. It was to get more stubborn. She lived in her car for months to reduce her own expenses while the company looked for other funding sources. Twelve turned to government grants and nonprofit programmes designed to bridge the gap between laboratory discovery and commercial viability. National Science Foundation grants came through. So did Department of Energy funding and a spot in the Advanced Manufacturing Office's Cyclotron Road programme in 2016, the same year Forbes gave the company its Change the World Award. In 2018, Twelve was a finalist for the Carbon Xprize. Recognition accumulated even as the venture capital rejections continued.

Their prototype catalyst was a thin black square roughly the size of a Post-it note. That square represented years of electrochemistry research and the absolute conviction of three people that the problem was solvable even when the people with the money disagreed.

The money eventually came

In 2021, Twelve returned to the venture capital market with a working prototype, government-validated technology and the early outlines of a commercial case. This time, it raised $57 million. In June 2022, it closed a $130 million Series B led by DCVC. By that point, the company had raised a total of approximately $199 million across six rounds and employed approximately 174 people, including electrochemists, material scientists and engineers recruited from research institutions around the world.

Then came the financing round that changed everything. In September 2024, Twelve announced $645 million in new capital: $200 million in Series C equity co-led by Capricorn Investment Group and Pulse Fund, $400 million in project equity committed by TPG Rise Climate Fund, and $45 million in credit facilities. It was one of the largest single financing rounds in the history of the e-fuels sector globally. The investor roster read like a roll call of corporate America's most visible climate commitments. Alaska Airlines. British Airways through its parent IAG. Microsoft. Amazon's Climate Pledge Fund. Coca-Cola's Sustainability Fund. Mitsui. SMBC. The company followed that round with an additional $83 million in February 2025, bringing the total raised across its history to approximately $927 million, comfortably exceeding the $900 million Cave has cited publicly.

What Twelve actually builds

The product is the AirPlant.

AirPlant One, Twelve's first commercial-scale manufacturing facility, is located in Moses Lake, Washington, and is now operational. It produces two products: E-Jet, a sustainable aviation fuel made from captured CO2, water and renewable electricity, and E-Naphtha, a feedstock for thousands of everyday industrial products. The process achieves lifecycle emissions up to 90 percent lower than conventional fossil jet fuel. Microsoft and Alaska Airlines joined the Twelve team to mark the commercial operation of the facility, described as the first plant in the United States to produce E-Jet fuel from CO2 at industrial scale.

Cave serves as Chief Science Officer. She leads the electrocatalysis research underpinning Twelve's patent portfolio, which spans catalysts, reactor design and electrochemical process engineering. Her co-founder Nicholas Flanders serves as CEO. The division of labour is deliberate. Cave's role is to ensure the science keeps advancing ahead of the commercial commitments the company is making to its airline and industrial customers.

The critics and the headwinds

None of this is without controversy, and Cave is clear-eyed enough not to pretend otherwise.

The sustainable aviation fuel sector has spent two decades making promises about how large a share of global jet fuel it would account for, and has spent two decades missing those targets. SAF currently represents approximately 0.3 percent of global jet fuel consumption despite enormous investment. The International Air Transport Association predicted in 2007 that SAF would account for 10 percent of jet fuel by 2017. That benchmark was never reached. A revised target of 3 percent by 2020 was also missed.

Environmental critics have questioned whether SAF is a genuine decarbonisation solution or primarily a mechanism that allows airlines to claim climate progress while continuing to expand operations. The Institute for Policy Studies published a report arguing that SAF production is "not moving at the speed of climate change" and could actively undermine net-zero goals. The broader carbon removal industry has also faced serious headwinds from the Trump administration's retreat from climate funding commitments, with competitors including Climeworks cutting more than 20 percent of their staff in 2025 citing economic uncertainty and shifting policy priorities.

Twelve's defenders argue that its power-to-liquid approach is fundamentally different from the crop-based biofuels that attract the most serious criticism. The company captures carbon from point sources, such as pulp and paper mills, ethanol plants and biogas facilities. It does not compete with food production and does not depend on the land-use accounting methodologies that critics most aggressively challenge. With its mix of private sector contracts and long-term project financing from institutions like TPG, Twelve also appears better insulated than government-dependent carbon removal companies. But no company in the sector is entirely immune to the policy uncertainty clouding the US clean energy landscape since 2025.

The recognition

The Smithsonian Institution has recognised Cave as a visionary. The US Department of Energy has featured her work in its public communications about the future of carbon utilisation. She has been profiled in Rolling Stone and Vanity Fair, which named her in its 2018 list of 26 Women of Colour Diversifying Entrepreneurship in Silicon Valley. She spoke at the Jeff Bezos-hosted MARS Conference, at Fortune Brainstorm and at the Aspen Ideas Festival. Her TEDx talk at Stanford outlined how recycled CO2 could reduce aviation's carbon footprint and potentially support future space travel.

She has also spoken directly about what it means to be a Black woman building a hard technology company in an industry that has historically had very few of either. The doors that did not open during the early fundraising years were not simply about the difficulty of the science or the unfamiliarity of the business model. "I figure I'd use my personal talents, which were interests in math and science, to create an impact," she said. "I liked the structure and understanding that came with science and math."

The company she built is now making fuel from air. The girl from Houston who watched a contaminated oil site go unaddressed and decided that someone needed to fix the system grew up to raise $900 million proving that she could be the one to do it.