Microsoft has signed a three-year agreement to purchase 36,920 metric tons of carbon dioxide removal credits from the Indian startup Alt Carbon. Marking the technology corporation’s initial enhanced rock weathering transaction in Asia, the credits will be delivered by 2029 from the Darjeeling Revival Project in eastern India. The contract contains provisions for Microsoft to acquire additional volumes provided that Alt Carbon achieves specified delivery and verification milestones. This transaction underscores the increasing role of suppliers from the Global South, who now account for approximately 26 percent of carbon-removal credit issuances globally.

The primary market challenge addressed by this agreement is the acute shortage of verified, commercial-scale suppliers within the carbon-removal sector. While numerous startups have emerged globally with promises to sequester atmospheric carbon dioxide, only a negligible fraction have successfully delivered verified credits at scale. Furthermore, international buyers have historically demonstrated skepticism regarding Indian carbon initiatives. This lack of verified supply and market confidence has restricted procurement options for major corporations attempting to fulfill stringent sustainability objectives.

To resolve these supply and verification constraints, Alt Carbon has deployed an enhanced rock weathering methodology utilizing crushed basalt sourced from the Rajmahal Traps. This material is distributed across approximately 80,000 acres of agricultural land in West Bengal, impacting more than 35,000 farmers. The basalt reacts with rainwater and atmospheric carbon dioxide to form stable bicarbonates, effectively sequestering the gas. To satisfy Microsoft’s rigorous corporate standards, Alt Carbon established proprietary monitoring, reporting, and verification infrastructure, including specialized laboratories in Bengaluru and Darjeeling to quantify carbon drawdown beyond standard registry baseline requirements.

The finalized transaction ensures a substantial multi-year credit supply for Microsoft, reinforcing its diversified procurement pipeline which also includes a separate 100,000-tonne 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 credit agreement established with the Indian firm Varaha. For Alt Carbon, the agreement validates its proprietary verification framework and supports a projected fivefold expansion of its agricultural deployment footprint over the next four to five years. The deployment credits will be officially issued through the Isometric carbon-removal registry, establishing a benchmark for high-measurement protocols within the region.