Microsoft has signed a three year deal to buy nearly 37,000 tonnes of carbon removal credits from Alt Carbon, an Indian startup using enhanced rock weathering. The credits come from the Darjeeling Revival project in eastern India, where ground basalt is spread on farmland to capture CO2 as stable bicarbonates in the soil. Delivery is expected by 2029, with additional volumes possible if verification goes well. The deal is notable because it is the first Asia wide agreement for this type of carbon removal. Alt Carbon has already issued around 10,000 credits through this method and plans to issue another 15,000 by the end of the year. Microsoft required extra monitoring and verification beyond standard registry requirements, which signals growing rigor in the voluntary carbon market. This purchase also highlights the increasing role of Global South suppliers in carbon removal. Alt Carbon says about 26% of credit issuances now come from these regions, up from roughly 2% in 2022. The credits will be issued through the Isometric registry, which supports enhanced rock weathering as a verified removal method.
