The Minneapolis-based startup Carba, in collaboration with the University of Minnesota, has developed a proprietary technology designed to remove carbon dioxide from the atmosphere by converting plant-based waste into biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More. This initiative, led by chemical engineering professor Paul Dauenhauer and Andrew Jones, utilizes a simple, low-cost reactor system that can be widely deployed to sequester carbon for over 1,000 years. By targeting the economic viability of carbon removal, the organization aims to transform ecological challenges into a trillion-dollar annual market opportunity.

The primary challenge addressed by Carba is the high cost and lack of scalability in current atmospheric carbon removal technologies. While global climate goals require massive reductions in greenhouse gases, existing engineered solutions often prove too expensive for widespread adoption or fail to provide a practical end-use for sequestered carbon. Furthermore, the accumulation of organic waste in settings like landfills typically leads to methane emissions, exacerbating the warming cycle rather than mitigating it.

Carba’s solution involves a portable, modular reactor that processes agricultural and municipal biomassBiomass is a complex biological organic or non-organic solid product derived from living or recently living organism and available naturally. Various types of wastes such as animal manure, waste paper, sludge and many industrial wastes are also treated as biomass because like natural biomass these More waste at relatively low temperatures to produce stable biochar. One of these reactors is currently operating at a Twin Cities-area sanitary landfill, where it not only sequesters carbon but also acts as an environmental filter. The resulting biochar is designed to be buried underground, effectively returning atmospheric carbon to the earth in a permanent, solid form.

The outcomes of this partnership include the validation of a scalable model for $100-per-ton carbon removal, a price point widely considered a tipping point for industry viability. Beyond carbon sequestration, the biochar produced at the landfill has demonstrated the potential to prevent harmful contaminants—including PFAS (“forever chemicals”), lead, and mercury—from leachingLeaching is the process where nutrients are dissolved and carried away from the soil by water. This can lead to nutrient depletion and environmental pollution. Biochar can help reduce leaching by improving nutrient retention in the soil.   More into the surrounding environment. This dual-benefit approach has positioned Carba as a leader in Minnesota’s growing bioeconomy, contributing to the state’s role as a hub for climate innovation.