Carbon capture has a crucial role to play in addressing climate change. While innovation in carbon capture, utilization, and storage (CCUS) is happening rapidly, there’s a long road ahead; scientists estimate we need to capture 10 billion metric tons of CO₂ per year, and we’re currently at about 50 million metric tons. The cost of this technology also needs to drop dramatically.

Think this sounds like a daunting challenge? That’s the kind of problem Harrison Rice loves to solve.

When Rice founded a sustainable ag and beverage company, he was told repeatedly that success in sustainable agriculture and consumer packaged goods was “effectively impossible.” He grew that company, Shaka Tea, to thousands of stores and saw it through to a successful exit. Rice says his takeaway from that experience is that “thinking at the scale of the problem is critical to success, especially when it comes to challenges others deem impossible.”

Interested in tackling another large-scale, “impossible” problem, Rice turned to direct air capture (DAC). From his perspective, DAC’s biggest challenge is efficiently processing large amounts of air, because CO₂ makes up just 0.04 percent of ambient air. 

GigaDAC is Rice’s answer to this challenge—a startup meeting the need for lower-cost DAC by fundamentally changing how DAC removes CO₂ from air. Rice partnered on GigaDAC with co-founder Barrett Kotnik, an aerospace engineer with a background that includes Lockheed Martin. More recently, the team added Dr. Yannick Eatmon, who earned his Ph.D. in chemical engineering from Princeton University, as its lead chemical engineer. 

Existing technologies move air through a filter, which creates a significant amount of resistance. Instead, GigaDAC uses a spray that binds to CO₂ molecules and a proprietary solution to remove the spray from the airflow. The system is six times more efficient, in terms of airflow resistance, than existing filter methods.

“Direct air capture is an airflow problem, and we are the first company to address the challenge primarily from this perspective,” Kotnik says.

“The heart and soul of our innovation is orienting the spray to be effective at capturing CO₂, and then secondly removing that spray at right next to 100 percent efficacy, and doing so with low pressure drop and high efficiency,” Rice says.

“Airflow efficiency is just part of the story,” adds Eatmon, explaining that with better airflow, the company is able to improve the kinetics between the solvent and CO₂. “With a boundary layer thickness less than one-tenth that of incumbent systems, we are able to work with a range of solvents that require significantly less energy to regenerate.”  

GigaDAC is currently building a commercial-scale pilot, which is on track to be completed in early 2025. Its next step will be a commercial-scale facility, to be finished 18-24 months after the pilot. 

The startup is raising its seed financing and plans to sell captured carbon, then profitably tap into the voluntary market and 45Q tax credit for CO₂ sequestration.

GigaDAC joined Greentown Houston last fall, and has been working closely with the Greentown team to support its prototyping.

“We’ve had a fantastic experience as Greentown members,” Rice says. “The team is very helpful to work with, we’re very excited to have our lab space up and running at Greentown Houston. This isn’t my first rodeo in terms of getting things that are logistically and technically challenging up and running, and the team was uniquely positive, helpful, and easy to work with, and the overall resources were really critical in getting what we’re doing off the ground.”