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1. Carba transforms low-value biomass into stable biochar using portable, energy-efficient reactors, enabling long-term carbon storage.
2. Their innovative approach reduces landfill waste and emissions while minimizing transportation costs for biomass disposal.
3. Carba's scalable model projects the removal of nearly 1 million tonnes of CO₂ annually within five years, given appropriate support.
In 2024, 4 Corners awarded grants to promising carbon removal projects across the U.S. One standout was Carba, a Minneapolis-based startup pioneering the conversion of natural waste into a powerful carbon storage tool: biochar. Founded by Andrew Jones, Carba is developing practical, scalable solutions to store carbon long-term while managing waste biomass sustainably.
Carba employs a process known as torrefaction, where biomass—such as dead or infested trees—is heated to 200-300°C in an oxygen-limited environment. This method transforms the biomass into biochar, a dense, solid form of carbon that can be safely stored underground or utilized in construction materials.
A significant innovation by Carba is their portable bioreactor, approximately the size of a wood chipper, allowing for on-site biochar production. This mobility reduces the need to transport heavy, bulky waste over long distances, conserving fuel, lowering emissions, and reducing costs.
Carba's initiatives extend beyond theoretical applications. They have launched projects in collaboration with organizations like Minnesota’s Waste Management, the Department of Energy, and GigaClimate. A flagship project, Carba’s Green Initiative, focuses on utilizing waste wood from Northern Arizona to produce biochar for landfill cover—a practice already implemented at Carba’s Burnsville, MN site.
This project sources wood waste from various locations, including Flagstaff, Boulder County, Salt Lake City, Santa Fe, and Albuquerque, demonstrating how regional cooperation can effectively address climate and waste challenges.
Carba's technology holds significant potential. With a single bioreactor, the company estimates the removal of 12,750 tonnes of CO₂ in the first year. Scaling up to 76 reactors over five years could result in nearly 1 million tonnes of CO₂ removed annually—all while diverting waste from landfills and reducing harmful emissions.
A cornerstone of Carba's model is Monitoring, Reporting, and Verification (MRV). They meticulously track the carbon removed to validate their claims. This rigorous approach ensures that carbon removal is a reliable tool for cities and communities aiming to reduce emissions.
Carba's work aligns with the mission of 4 Corners: supporting community-based, scalable carbon removal. By addressing waste and emissions concurrently, Carba exemplifies how local governments can adopt carbon removal strategies that are cost-effective, efficient, and environmentally responsible.
As more cities seek methods to reduce their carbon footprint, Carba's portable, practical solution offers a compelling example of what's achievable.
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