Bangalore, India - 11th June 2026: Alt Carbon, a deeptech startup building Planetary Intelligence, today announced a deal with Microsoft to remove up to 36,920 metric tons of CO₂ in a multi-year deal. This will be Microsoft’s first deal in Asia to purchase carbon credits generated through Enhanced Rock Weathering (ERW).
Microsoft will receive verified Carbon Dioxide Removal (CDR) credits from the Darjeeling Revival Project (DRP) — an ambitious initiative to revive Darjeeling’s heritage tea estates and neighboring agricultural networks like rice paddies, by making it a hub for removing CO₂ at scale. Alt Carbon has onboarded over 80,000 acres of agricultural land to date, working with more than 35,000 farmers in 60+ gram panchayats, creating 250+ green jobs across field operations, logistics, and laboratory monitoring in the state of West Bengal, India.
Alt Carbon generates carbon credits via Enhanced Rock Weathering, which involves sourcing waste basalt rock and spreading it across agricultural farmlands. The basalt reacts with carbon dioxide dissolved in rainwater; permanently storing the carbon dioxide as stable bicarbonate ions. Over time, these ions travel through river networks to the ocean, where they eventually reside as calcium carbonate (CaCO₃), in the form of corals & seashells for over 1,000 years. The Darjeeling Revival Project further adapts agriculture to climate impact by boosting soil health, balancing pH, and improving crop yields for farmers.
Alt Carbon has issued 9,566 Carbon Credits to date via Isometric. While the Carbon Dioxide Removal (CDR) market has reached new heights, actual verified issuances continue to lag. Alt Carbon’s record of scalable, repeated deliveries is advancing the field of Enhanced Rock Weathering while deepening trust in Indian carbon projects.
In order to scale up its operations, Alt Carbon, which is backed by leading global investors like Lachy Groom, Shastra VC, iSeed Ventures, Awais Ahmed (Pixxel), & Paras Chopra (Lossfunk), has set up state of the art Earth Sciences labs across the country. Shonku Labs conducts core R&D at the Bangalore Headquarters inside the Indian Institute of Science (IISc), while the Darjeeling Climate Action Lab (D-CAL), located at Kamala Tea Estate, provides lab processing for Alt.
The in-house laboratory capacity and field monitoring systems help quantify carbon fluxes, soil chemistry changes, monitor environmental safeguards, and build novel soil and river datasets to model Planetary Intelligence. D-CAL will overcome the constraints of sampling, testing and verification methodologies by processing up to 100,000 samples annually by 2026. By expanding laboratory throughput and field measurement capacity, Alt Carbon aims to reduce the cost of Measurement Reporting and Verification (MRV) over time, helping lower the overall cost of high-integrity carbon removal credits. Alt Carbon has analysed and processed more than 20,000 samples to date.
In addition to delivering verified Carbon Dioxide Removal (CDR) credits to Microsoft, Alt Carbon will expand field trials, conduct deep soil and porewater monitoring, collect crop uptake measurements, and commit to public data-sharing to advance the field. The offtake is aimed at advancing the scientific understanding of ERW in tropical agricultural systems, studying its potential scaling through the Global South.
“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.
The deal also provides Microsoft the opportunity to purchase additional volumes from Alt Carbon subject to successful delivery and verification milestones, supporting continued expansion of ERW deployments & biochar projects across India.
As demand for verified ERW grows, Alt Carbon is launching Alt Explorers, a bespoke executive education and immersion program designed to shorten the path from Net Zero planning to multi-year procurements, offering direct access to Alt Carbon's field operations, laboratory infrastructure, and MRV methodology. This invite-only program is designed for senior decision-makers across sustainability, marketing, and finance. Companies can express their interest here altcarbon.com/remove-co2.
“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.
“Our contract with Alt Carbon for high-quality carbon removal uses field deployments to collect primary and secondary quantification methods for carbon quantification, while using a high standard to safeguard against environmental impacts. We are encouraged by Alt's efforts to build durable carbon removal capacity in India given their past success in delivering carbon credits,” said Phil Goodman, Program Director, Carbon Removal, Microsoft.
Notes to the Editor
For further information, please contact the Alt Carbon press office:
Adithya Venkatesan — [email protected]
About Alt Carbon
Alt Carbon is a deeptech science and data company, building infrastructure for Planetary Intelligence. We aim to make South Asia a hub for Carbon Dioxide Removal (CDR) through technology pathways like Enhanced Rock Weathering and Biochar. We work with farmers and scientists in the Global South, to turn underutilized land into carbon sinks. Our flagship initiative, the Darjeeling Revival Project (DRP), is a first-of-its-kind effort to unite climate action with cultural and ecological restoration — by reviving degraded soils, restoring livelihoods, and rebuilding ecosystems. This year, we also launched the Bengal Renaissance Project (BRP), an industrial biochar program that is building a network of biomass banks, and pyrolysis and gasification plants across Eastern India, with a mission to weave hope back into the lands of India. We’re rooted in science, powered by community, and driven by the belief that revivals require ambitious people and audacious bets. Alt Carbon is based out of Bangalore/Darjeeling & was founded by tea planter siblings Sparsh & Shrey Agarwal. The latest seed round was led by Lachy Groom. Our mission is to remove 5 million metric tons of CO₂ by 2030.