Carbon credit procurement platform Senken announced today that it has signed a multi-year carbon removal offtake agreement with CO2 removal technology company Carbonsate, covering 50,000 tons of permanent carbon removal, marking the largest biomass storage deal signed in Europe to date.

Berlin-based Carbonsate develops biomass storage projects that deliver permanent carbon removal by storing waste wood in engineered underground storage chambers. Each storage site is supported by a proprietary monitoring, reporting and verification (MRV) system and independently verified under the Puro.earth standard.

According to the companies, the agreement also marks the second-largest buyer commitment in the biomass geological storage (burial) category worldwide, and the largest for a project operating in Africa.

Biomass storage, also known as biomass burial, prevents the carbon in waste wood from returning to the atmosphere by storing the wood in sealed, engineered underground chambers, where it cannot burn or decompose, enabling the carbon to remain locked away for centuries. According to the companies, the method does not require an energy-intensive capture step, enabling it to deliver permanent carbon removal at a fraction of the cost of direct air capture.

Under the agreement, the carbon will be removed through Carbonsate’s biomass geological storage project in Namibia, with deliveries expected to begin this year and to continue through 2028.

Johanna Broell, Co-founder and CEO, Carbonsate, said:

“Long-term commitments like this one give project developers the certainty to build ahead of demand. This agreement supports the expansion of our Namibia storage sites and brings meaningful new supply of verified, high-integrity carbon removal to the market.”

Founded in 2022, Berlin-based Senken provides a carbon credit procurement platform that helps companies source, assess and purchase high-quality carbon credits and build carbon offsetting strategies. With its Sustainability Integrity Index (SII), Senken vets every credit against 600+ data points, rejects 95% of market projects, and delivers audit-ready documentation, the company said. Senken said that its platform supports large European companies, including Deutsche Telekom, Vodafone, and DZ Bank.

Adrian Wons, CEO, Senken, said:

“Demand for permanent carbon removal is already outrunning supply: corporate net-zero targets all point to the same small pool of verified capacity. That gap will define the market for the next decade. We committed for multiple years to secure access for European buyers to credible removal at prices they can plan with.”