Microalgae-based carbon capture is being deployed at street level in Indian cities, and the numbers are surprisingly concrete.

A Scroll.in / Deutsche Welle documentary follows companies Lo Carbon Solutions and Zaara Biotech as they install bioreactor systems in Kochi, Mumbai, and Bengaluru. The technology uses microalgae’s Carbon Dioxide Concentrating Mechanism (CCM), which allows these organisms to sequester CO2 faster than land plants, even in polluted urban conditions.

The Hardware

Two systems are featured:

The “Liquid Tree” is a 1,000-liter bioreactor that absorbs approximately 180 grams of CO2 per day. The developers claim this matches the annual carbon absorption of 10 mature trees. It runs at busy junctions and roadsides, treating ambient air in real time.

The “Obelia” unit is smaller — a 300-liter system absorbing roughly 80 kg of CO2 per year. Multiple units are deployed across Indian cities as part of urban pollution mitigation projects.

Research Backing

The work is a collaboration between commercial companies and academic institutions, including the Kerala University of Fisheries and Ocean Studies (KUFOS) and Catholicate College. Dr. Binoy T. Thomas explains the CCM mechanism that gives microalgae their CO2 uptake advantage over terrestrial plants.

Why This Matters

Microalgae CDR occupies an interesting niche: it operates at small scale in urban environments where air quality co-benefits are immediately visible to residents. That visibility matters for public acceptance of carbon removal technologies.

India’s CDR ecosystem is growing. According to the CaptainDrawdown CDR Company Directory, multiple Indian companies now work on biological carbon removal pathways, though microalgae-focused operations remain uncommon.

The full video is worth watching — it shows deployed hardware, not just lab prototypes.

Sources

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