Minnesota’s Carba raises $6M to scale landfill carbon removal, eyes Asia expansion

Eden Prairie, Minnesota-based startup Carba, which converts waste biomass into long-lived biocarbon, announced Wednesday that it had closed a $6 million investment round. The round is led by Rusheen Capital Management and the Canopy Generations Fund, with participation from several venture and regional investors.

The financing is intended to accelerate the firm’s technology and commercial rollout, company executives said, and to support expansion into the Asia-Pacific region. Carba develops autothermal pyrolysis reactors and anoxic burial methods aimed at producing a stable form of carbon from organic waste that can be buried in landfills and certified as permanent carbon removal.

Carba’s first project is being commissioned in Burnsville, Minnesota, where biocarbon produced from municipal wood and utility-corridor vegetation will be buried at the Burnsville Sanitary Landfill. The company expects production to begin this year, with the first deliveries certified by the Isometric registry projected for the first quarter of 2026. Carba says the Isometric certification will attest to durability of more than 1,000 years.

Carba previously announced a five-year, 44,000-ton carbon-credit offtake agreement with Microsoft and noted selection for a U.S. Department of Energy grant under the Carbon Negative Shot program. Those agreements and awards, if realized, would support the firm’s early commercial footprint.

Investors who joined the round include Groove Capital, Demos Fund, Collaborative Fund, Incite, Grid Catalyst, and several Minneapolis-based backers. “Carba’s solutions represent the kind of innovations the world needs now. Carba is one of the most technically credible and quickly scalable carbon removal companies we’ve seen,” Sonia Tsao, Partner at Canopy Generations Fund said in the statement.

Carba’s process produces a form of biocarbon intended for three uses according to the company: permanent atmospheric carbon removal through burial, pollution management within landfill sites, and material applications. The company describes its reactor and burial methods as patent-pending and its founders include researchers with decades of experience in pyrolysis and biomass valorization.

Carba plans to bring its Burnsville facility online in late 2025 and pursue further U.S. projects while building an Asia-focused business unit for project development and supply-chain partnerships. The firm said the new capital and partnerships will help it pursue ‘gigaton-level’ climate infrastructure ambitions, though it did not provide a specific timeline or capacity targets for that scale.