• Microsoft will buy up to 36,920 metric tons of verified carbon removal credits from Alt Carbon’s Enhanced Rock Weathering operations in India.
• The Darjeeling Revival Project spans more than 80,000 acres, working with over 35,000 farmers across 60+ gram panchayats in West Bengal.
• Alt Carbon has issued 9,566 verified carbon credits to date, strengthening India’s role in high-integrity carbon removal markets.

Microsoft Enters Asia’s ERW Market Through India

Microsoft has signed a multi-year carbon removal agreement with Alt Carbon, marking the technology company’s first purchase in Asia of carbon credits generated through Enhanced Rock Weathering.

Under the deal, Microsoft will receive up to 36,920 metric tons of verified Carbon Dioxide Removal credits from Alt Carbon. The credits will come from the Darjeeling Revival Project in West Bengal.

The agreement gives Microsoft exposure to one of the most closely watched pathways in durable carbon removal. It also places India more firmly inside the global market for high-integrity engineered removals.

For Alt Carbon, the deal brings a major corporate buyer into a project built around science, farmland, and local employment. The company has onboarded more than 80,000 acres of agricultural land to date. It works with over 35,000 farmers across more than 60 gram panchayats.

The project has also created more than 250 green jobs across field operations, logistics, and laboratory monitoring.

How the Darjeeling Project Removes Carbon

Alt Carbon uses Enhanced Rock Weathering, or ERW, to generate carbon removal credits. The process involves sourcing waste basalt rock and spreading it across agricultural land.

When rainwater interacts with the basalt, it helps convert dissolved carbon dioxide into stable bicarbonate ions. These ions eventually move through river systems toward the ocean. Over time, the carbon can reside as calcium carbonate in forms such as corals and seashells for more than 1,000 years.

The Darjeeling Revival Project is also designed to support climate adaptation in agriculture. Alt Carbon says the process can improve soil health, balance pH levels, and help strengthen crop yields for farmers.

That local co-benefit is central to the project’s market positioning. Buyers of carbon removal credits are under rising pressure to prove durability, environmental integrity, and social value.

Alt Carbon has issued 9,566 carbon credits to date through Isometric. The company says this delivery record is important because verified issuances still lag behind demand in the broader carbon removal market.

Labs, MRV, and the Cost of Trust

The Microsoft deal is also a bet on measurement. Enhanced Rock Weathering has attracted growing interest from corporate buyers, but its credibility depends on strong monitoring, reporting, and verification.

Alt Carbon has built in-house laboratory capacity to support that work. Shonku Labs conducts core research and development at the company’s Bangalore headquarters inside the Indian Institute of Science. The Darjeeling Climate Action Lab, located at Kamala Tea Estate, handles lab processing for Alt Carbon.

Together, these facilities help quantify carbon fluxes, track soil chemistry, monitor safeguards, and build datasets for what the company calls Planetary Intelligence.

Alt Carbon has analysed and processed more than 20,000 samples to date. Its Darjeeling lab is expected to process up to 100,000 samples annually by 2026.

That scale matters for investors and corporate buyers. Lower MRV costs could reduce the overall cost of high-integrity carbon removal credits. It could also support wider ERW deployment across tropical agricultural systems.

As part of the Microsoft offtake, Alt Carbon will expand field trials. It will also conduct deep soil and porewater monitoring, collect crop uptake measurements, and share public data to support the wider field.

India’s Role in Carbon Removal

“Alt Carbon is dedicated to undertaking frontier research to map out our planet. Our deal with Microsoft is built upon years of work building high-integrity carbon removal infrastructure in India. From laboratory capabilities to field operations and farmer networks, we have focused on advancing the science of rock weathering globally. Over the past few years, we have measured and indexed thousands of soil and water samples across land parcels covering an area roughly twice the size of Manhattan. Climate Change remains one of the most significant civilizational challenges we face & India can be a global leader in tech based carbon removal,” said Shrey Agarwal, CEO and Co-founder of Alt Carbon.

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The agreement also gives Microsoft the option to purchase additional volumes from Alt Carbon. Those purchases are subject to successful delivery and verification milestones. Future expansion could include additional ERW deployments and biochar projects across India.

Alt Carbon is backed by global investors including Lachy Groom, Shastra VC, iSeed Ventures, Awais Ahmed of Pixxel, and Paras Chopra of Lossfunk.

The company is also launching Alt Explorers, an invite-only executive education and immersion program. It is aimed at senior leaders in sustainability, marketing, and finance. The goal is to move companies from net zero planning toward multi-year procurement.

What Executives and Investors Should Watch

For C-suite leaders, the Microsoft agreement highlights three governance questions. Buyers must assess whether carbon removal suppliers can verify delivery, scale responsibly, and manage local environmental impact.

For investors, the deal points to a widening market for Global South carbon removal. Lower costs, suitable geology, and agricultural land networks could improve project economics. But scientific scrutiny will remain high.

For policymakers, the transaction adds momentum to India’s role in climate technology. It connects rural land systems with global corporate decarbonization budgets.

“ERW is emerging as a scalable and rigorous pathway for Carbon Removal technologies globally. This is a scientific breakthrough that could have the capacity to scale across the Global South (with a potential to remove up to 2 gigatons of CO2 annually). In fact, the numbers tell a clear story about the market: Global South suppliers now account for 26% of CDR issuances, up from under 2% in 2022. This transformation is driven by the combination of favourable geologies, lower costs, and a new generation of science-first developers. The efficiency gap is equally striking: for every dollar of funding, Global South suppliers have produced 15 times as many engineered carbon removal credits as their counterparts in the Global North. Alt Carbon sits at the centre of this shift — bringing together cutting-edge science, operations that move with velocity, and the lab infrastructure needed to meet the standards that buyers like Microsoft demand,” said Sparsh Agarwal, President and Co-founder of Alt Carbon.

Microsoft’s purchase does not solve the carbon removal market’s verification challenge. But it does show where demand is moving.

Durable removals are shifting from pilot projects into structured procurement. India now has a larger claim in that transition.