Alt Carbon Secures $12 Million to Scale Carbon Removal Initiative in South Asia
Innovative Climate-Centric Startup Aims for Significant Carbon Dioxide Reduction
Alt Carbon, a groundbreaking climate-tech startup focused on carbon dioxide removal, has successfully raised $12 million in a seed funding round. This funding will enable the company to enhance its sustainable practices in the South Asian region, particularly by leveraging enhanced rock weathering techniques on agricultural lands. The investment was led by Lachy Groom, a prominent co-founder of the AI robotics firm Physical Intelligence.
From Tea Estate to Climate Solution
The foundation of Alt Carbon was laid during a pivotal moment in May 2020, when siblings Shrey and Sparsh Agarwal traveled 16 hours from Kolkata to their family tea estate, Salem Hill, in Darjeeling—an area renowned for its tea cultivation in the foothills of the Himalayas. Initially intended as a farewell due to impending bankruptcy, this visit catalyzed the inception of Alt Carbon, which officially launched in late 2023.
With an aim to revitalize their family business, the Agarwals investigated carbon markets as a potential source of supplementary income for struggling tea estates in the area. In the process, they discovered enhanced rock weathering, which could transform Darjeeling’s legacy from vulnerability to climate change into a hub of climate action initiatives.
“The existing carbon projects in India are largely avoidance-based and often lack quality, leading to ineffective credits,” Sparsh remarked during an interview with TechCrunch.
Launching a Pilot Program
In 2022, Alt Carbon initiated a pilot project on approximately 500 acres of land surrounding the Agarwals’ estate. The startup has since expanded its efforts to include rice and bamboo farms across North Bengal, with plans to scale up to 500,000 hectares by 2030. The target is to remove five million tons of carbon emissions from the region.
Unique Method of Carbon Removal
Alt Carbon employs enhanced rock weathering by utilizing waste basalt rock dust sourced from local mining and quarrying operations in Eastern India’s Rajmahal region. By spreading this basalt dust across agricultural fields, the startup aims to facilitate a natural reaction with rainwater, which removes carbon dioxide and enriches the soil with micronutrients, thereby enhancing crop yields. When rainwater saturated with carbon dioxide engages with basalt dust, it converts into stable bicarbonate ions, which are ultimately carried to the ocean as calcium carbonate, effectively sequestering carbon for over 10,000 years.
Transport logistics incorporate existing freight systems used by the tea industry, employing both rail and diesel trucks for delivery, thus minimizing emissions associated with dedicated rock processing.
Innovative Blends for Farmer Engagement
To encourage farmers to adopt this innovative approach, Alt Carbon has developed a unique blend of basalt dust combined with organic materials, branded as "Hari Maati" (green soil in Hindi). This mix is designed not only to improve soil fertility but also to foster broader engagement with local agricultural communities.
The startup estimates its carbon credits can be valued at $270 per metric ton, significantly lower than the estimated $800 per ton for direct air capture credits. Alt Carbon aims to reduce costs further within 36 to 48 months.
Comprehensive Measurement Techniques
Monitoring the effectiveness of its carbon removal process is critical for Alt Carbon, which employs a three-tiered measurement strategy. Initially, the company tracks the progress of weathering, followed by soil water content assessments and groundwater sampling. The third layer incorporates proprietary reactive transport models to analyze the movement of ions from soil into water bodies. Additionally, machine learning models are utilized to quantify carbon removal accurately.
Alt Carbon’s methodologies align closely with standards set by carbon removal registries such as Isometric and Puro.earth, receiving endorsements from several intergovernmental organizations, including SBTi, ICVCM, and CORSIA.
Future Plans and Partnerships
Positioned in Darjeeling and Bengaluru, Alt Carbon employs a team of 25, including 8 to 10 PhD-level researchers. The company is dedicated to expanding its laboratory capabilities, enhancing soil analysis procedures, and establishing a hardware studio for improved data collection via remote sensing technologies. Plans also include deploying ground sensors for enhanced data acquisition.
In addition to securing $500,000 in pre-purchase funding from Frontier and a $1 billion advanced market commitment from industry leaders like Stripe and Alphabet, Alt Carbon has formed a strategic partnership with NextGen, which involves entities such as South Pole and Mitsubishi Corporation. Recently, the startup signed an offtake agreement with Japan’s MOL Group to sell 10,000 tons of carbon removal credits.
Alt Carbon is set to deliver its first carbon credits within the next month through Isometric, marking a significant milestone in their journey toward a sustainable future.
