Senken has signed what it describes as the largest biomass storage deal in Europe to date, a multi-year carbon removal offtake with Berlin-based Carbonsate covering 50,000 tonnes of permanent carbon removal between 2026 and 2028.
Deliveries under the agreement begin this year. The deal ranks as the second-largest buyer commitment in the biomass geological storage category worldwide, and the largest tied to a project operating in Africa. The carbon will be removed from Carbonsate’s Puro.earth-verified storage project in Namibia.
Permanent carbon removal remains a small market. The sector has delivered roughly 1.5 million tonnes globally to date, meaning this single commitment accounts for about 4% of total supply so far.
Adrian Wons, chief executive of Senken, said demand for permanent removal is already outpacing supply, as corporate net-zero targets compete for the same limited pool of verified capacity. He said the multi-year commitment was designed to secure European buyers access to credible removal at predictable prices.
Johanna Broell, co-founder and chief executive of Carbonsate, said long-term agreements like this one give project developers the certainty needed to expand ahead of demand, supporting growth at the company’s Namibia storage sites.
Biomass storage works by sealing waste wood in engineered underground chambers, where it cannot burn or decompose. The carbon it contains stays locked away for centuries. Because the process skips the energy-intensive capture step required by direct air capture, proponents say it delivers permanence at a lower cost.
Carbonsate’s storage sites are monitored through a proprietary system and independently verified under the Puro.earth standard.
