Indian Startup Uses Rock Dust to Fight Climate Change, Raises $12 Million
When it rains on certain farms in North Bengal, something special is happening. The raindrops are silently pulling harmful carbon dioxide from the air with help from a green powder spread across the fields.
This innovative approach comes from Alt Carbon, an Indian startup that just secured $12 million in seed funding to expand their carbon removal technology. According to TechCrunch, the company was founded by siblings Shrey and Sparsh Agarwal and is already making waves in the growing carbon removal industry.
The Story Behind Alt Carbon’s Green Mission
The Agarwal brothers began their journey in May 2020 with a personal connection to the land. Their family owned a tea estate in Darjeeling that they wanted to revitalize. But their vision quickly grew beyond one farm. They saw an opportunity to help farmers across North Bengal while tackling climate change at the same time.
Based in both Darjeeling and Bengaluru, Alt Carbon officially launched in late 2023 after years of careful research and development. The company is now set to deliver its first carbon credits in less than a month, marking a major milestone in their growth.
How Does Rock Dust Remove Carbon? A Simple Explanation
Alt Carbon’s approach is based on a process called enhanced rock weathering, which speeds up a natural way the Earth has been cleaning the air for millions of years. Their special ingredient is a product they call “Hari Maati” (meaning green soil in Hindi).
Here’s how it works in simple steps:
- First, Alt Carbon collects waste basalt rock dust from mines in Eastern India’s Rajmahal Traps. This dust would otherwise be discarded, but it contains minerals that can naturally react with carbon dioxide.
- Next, they create their special “Hari Maati” mixture, which is customized for different types of farmland. This green powder is completely safe and certified by multiple organizations including USDA Organic.
- Farmers spread this mixture on their fields where it waits for rain. When rainwater falls, it contains small amounts of carbon dioxide that react with the rock dust.
- This chemical reaction transforms the carbon dioxide into stable bicarbonate ions that stay in the soil and eventually make their way to the ocean, where they’re stored as calcium carbonate for over 10,000 years.
What makes this approach remarkable is that it can remove over 25% of carbon dioxide while also adding helpful nutrients to the soil. According to IAS Gyan, just 3-4 tonnes of basalt dust can trap 1 tonne of carbon in 2-4 years – a process that would naturally take about 1,000 years.
Benefits for Farmers and Their Crops
The beauty of Alt Carbon’s approach is that it helps farmers while fighting climate change. The rock dust adds important micronutrients to the soil, potentially improving crop health and yields. The company is currently working with tea, rice, and bamboo farms across North Bengal.
With plans to expand to 500,000 hectares of land, Alt Carbon is creating a model that could transform agriculture across India while removing harmful carbon from the atmosphere.
Creating High-Quality Carbon Credits in India
Carbon credits are certificates that represent one tonne of carbon dioxide removed from the atmosphere. Companies buy these credits to offset their own emissions. But not all carbon credits are created equal.
“Within carbon markets, our realization was that a lot of the projects in India, which are more avoidance-based, are of very low quality, and they produce junk credits,” explained co-founder Sparsh Agarwal.
Unlike many existing projects that simply avoid releasing new carbon, Alt Carbon actively removes carbon that’s already in the air. Their credits are currently priced at about $270 per metric ton, though this cost is expected to decrease over the next 3-4 years as they scale up operations.
The quality of their approach has attracted major investors including Lachy Groom, co-founder of robotics AI company Physical Intelligence, and a buyer coalition called NextGen that includes global giants like BCG Group, Swiss RE, and UBS. Other notable investors include Frontier, Stripe, Alphabet, Meta, Shopify, and McKinsey.
Future Growth and Impact
Alt Carbon aims to remove 5 million tons of carbon dioxide annually by 2030. This would make them a significant contributor to India’s carbon removal efforts, as the country expects to trade over 250 million carbon credits domestically by 2025, according to NetZeroIndia.
The company recently signed an important deal with Japan’s MOL Group for 10,000 tons of carbon removal credits. With approvals from respected organizations like SBTi, ICVCM, and CORSIA, Alt Carbon is positioning itself as a leader in high-quality carbon removal.
With a team of 25 employees, including 8-10 PhDs, Alt Carbon is showing how innovative thinking can turn waste rock dust into a powerful weapon against climate change, while helping farmers and creating new economic opportunities in India.
