Microsoft has solidified its commitment to environmental sustainability by entering into a significant three-year agreement with the Indian startup Alt Carbon. The deal involves the purchase of nearly 37,000 metric tons of carbon removal credits, marking the tech giant’s first foray into enhanced rock weathering projects within the Asian market. The credits will be sourced from the Darjeeling Revival Project, with the potential for additional volume purchases contingent upon the startup meeting specific verification milestones.

Alt Carbon, a Bengaluru-based firm founded in 2023, utilizes enhanced rock weathering—a process that involves spreading crushed basalt on agricultural land to accelerate natural chemical reactions that sequester carbon dioxide. By partnering with over 35,000 farmers across 80,000 acres, the startup has established a scalable model that converts atmospheric carbon into stable bicarbonates. This agreement follows a rigorous scientific review and due diligence process, with Microsoft mandating stringent monitoring, reporting, and verification protocols to ensure the integrity of the credits.

This partnership highlights a broader shift in the carbon credit market, where buyers are increasingly prioritizing verified, high-quality projects over speculative ventures. As the global demand for carbon removal grows, developers in the Global South are playing an increasingly vital role, with their share of credit issuances rising significantly in recent years. For Alt Carbon, the deal serves as a validation of its proprietary measurement infrastructure and its ability to deliver commercial-scale results in a competitive and skeptical international market.

Beyond this latest agreement, Microsoft continues to diversify its carbon removal portfolio in India, having previously secured a deal with the startup Varaha for biochar-based credits. As Alt Carbon looks to expand its operational footprint fivefold over the next few years, the collaboration underscores the importance of technological innovation and rigorous data-sharing in meeting corporate net-zero targets.

Key Takeaways

• Microsoft has signed a deal for nearly 37,000 metric tons of carbon removal credits from Indian startup Alt Carbon, focusing on enhanced rock weathering.
• The project utilizes crushed basalt spread across 80,000 acres of farmland to sequester carbon dioxide, with verification managed through the Isometric registry.
• The agreement signals a growing trend of international corporations sourcing high-quality, verified carbon credits from emerging markets in the Global South.

Editor’s Analysis & Impact

The partnership between Microsoft and Alt Carbon is a bellwether for the maturing voluntary carbon market. By moving beyond simple offsets toward high-integrity, scientifically verified removal methods like enhanced rock weathering, Microsoft is setting a benchmark for corporate climate accountability. The industry is currently plagued by a ‘verification gap,’ where supply is abundant but credible, measurable data is scarce. Alt Carbon’s investment in its own MRV (monitoring, reporting, and verification) infrastructure provides a competitive moat that addresses this exact pain point. Looking ahead, we expect to see increased capital flow into the Global South as tech giants seek scalable, nature-based solutions that offer both environmental impact and verifiable data. This trend will likely force smaller carbon-removal startups to adopt more rigorous scientific standards to remain viable in a market that is rapidly shifting toward quality over quantity.

Frequently Asked Questions

Q: What is enhanced rock weathering?
A: It is a carbon removal technique that involves spreading crushed silicate rocks, such as basalt, over farmland. These rocks react with rainwater and atmospheric carbon dioxide to form stable bicarbonates, effectively locking the carbon away.

Q: Why is Microsoft investing in Indian carbon projects?
A: Microsoft is seeking high-quality, verified carbon removal credits to meet its ambitious net-zero goals. India offers large-scale agricultural land suitable for these projects, and startups like Alt Carbon have developed the necessary scientific infrastructure to provide the rigorous verification that Microsoft requires.