Amid rising air pollution, Greenwater Scientific introduces a ₹63k alternative to air purifiers

GURUGRAM, India , Nov. 4, 2026 /PRNewswire/ -- Greenwater Scientific is bringing photosynthesis into Indian homes with the greenwaterHOME Air Synthesizer. The device uses living microalgae to absorb carbon dioxide and release oxygen, alongside Pre, HEPA and activated carbon filters for dust, smoke and pollutants. It is available across India at ₹63,720.

The device holds a living microalgae culture that draws carbon dioxide out of indoor air and returns oxygen to the room, alongside HEPA and carbon filters for dust and fumes. It comes out of more than three years of research and development. In the company's sealed-room tests, CO₂ fell by an average of 32% every hour, and an NABL-accredited laboratory measured a 95.1% drop in PM2.5.

Indian cities have taught everyone to worry about the air outside: dust from building sites, smoke from burning stubble, exhaust from traffic. Far less attention goes to the air we create at home. Each breath adds a little carbon dioxide to the room, and with the doors and windows closed, it builds up within a few hours. Filters do nothing about it, and that is the gap the Air Synthesizer was designed to fill.

Why Not Just Get a Plant?

Roughly 3/4th of the oxygen on Earth is produced by phytoplankton and microalgae drifting in the ocean. Forests and other land plants make most of what's left. A flat in Gurugram or Mumbai uses oxygen all day and produces almost none.

Houseplants help less than most people expect. Ordinary indoor lighting is too weak, and the wrong spectrum, for proper photosynthesis. Plants by a window gather dust on their leaves, which cuts the light they can use. Even a well kept plant, with good light, clean leaves and regular watering, makes about 0.4 litres of oxygen a day, based on leaf-science data published by Ugaoo.

The Air Synthesizer makes 46 litres of oxygen a day, as measured by an NABL-accredited laboratory. Matching that would take around 80 houseplants.

Why algae

A plant puts much of its energy into roots, stems and leaves, and only part of its body does photosynthesis. A microalga is a single cell packed with chlorophyll. It photosynthesises over its whole surface and keeps dividing. For their size, algae are far better than plants at turning carbon dioxide into oxygen, and they need very little space to do it.

Algae grow best in a photobioreactor, a vessel that manages light, carbon dioxide, temperature and nutrients while keeping contamination out. Greenwater Scientific grows every culture it ships in its own photobioreactor lab at its Gurugram headquarters. The Air Synthesizer is a compact version of the same equipment, built for a living room.

Inside the unit, a fan pulls room air through water that holds the algae. The CO₂ in that air dissolves, the algae take it up, and oxygen rises back out into the room.

What a closed room does to you

People now track their sleep, heart rate variability, blood oxygen, recovery and strain in close detail, and most of the work to improve those numbers goes into the body itself. The room matters as well. Shut the door and the air starts to change, with CO₂ creeping up for as long as anyone stays inside.

Opening a window is the obvious fix, though in most large Indian cities the heat, the noise or the pollution outside usually rules it out. Photosynthesis is the other way to bring CO₂ down. Greenwater Scientific tested the Air Synthesizer in a sealed, insulated 8 × 8 × 8 ft room filled with more than 3,000 ppm of CO₂, measuring levels every 15 minutes, every day from 14 November to 12 December 2025. With the device running, CO₂ fell by an average of 32% an hour (±3%) and dropped below 1,000 ppm in about three hours. Without it, levels stayed above 3,000 ppm.

Furniture first

Most air purifiers are tolerated rather than liked, and plenty end up in a corner once the smog season passes. "They look like sitting reminders that the world is coming to an end," said Dhruv Mehta, co-founder of Greenwater Scientific. "We wanted something that fits into your interior design and does a job at the same time."

The Air Synthesizer doubles as a side table, with a flat top for a coffee mug, a photo frame or a few books. Through its clear panel you can watch the culture shift from pale to deep green as it grows over the weeks. The darker it gets, the more CO₂ the algae are taking in.

Filters for the air from outside

Alongside the algae, the unit carries an H13-grade HEPA filter made of microfibre glass and an activated carbon fibre filter with a honeycomb mesh. The HEPA layer traps fine dust and smoke particles, much of which comes in from outdoors. The carbon layer absorbs VOCs such as benzene, which are given off by paint, cleaning products and furniture.

An NABL-accredited laboratory measured reductions of 95.1% in PM2.5, 95.7% in PM10 and 77.9% in benzene under test conditions.

From a documentary to a living room

Dhruv Mehta got the idea while watching a Netflix documentary that explained how much more efficient algae and phytoplankton are at photosynthesis than trees. One question stayed with him: "Then why have we always been taught to grow more plants to fight air pollution, if nature already has a more effective resource?"

Proving the concept could work in a home took time. From then on, the team's guiding principle was to recreate the conditions of the ocean as closely as they could.

Microalgae and their cousins, cyanobacteria, helped give Earth a breathable atmosphere. They were making oxygen long before trees, long before dinosaurs, and long before any creature with lungs came along to breathe it. Nobody has thanked them for it yet.

The Air Synthesizer takes that 3-billion-year-old process out of the ocean and puts it next to your sofa.

About Greenwater Scientific

Greenwater Scientific is an Indian biotechnology company developing micro-algae technology for indoor air care. Co-founded by Dhruv Mehta and Sumir Mehta, the company combines research originating at the University of California San Diego with engineering and manufacturing in Manesar, Haryana.

Its flagship product, the greenwaterHOME Air Synthesizer, uses living micro-algae to absorb carbon dioxide and release oxygen through photosynthesis, alongside three-stage filtration to remove airborne pollutants.

Greenwater Scientific has participated in the Blackstone LaunchPad Accelerator, received U.S. Congressional recognition, and won the Grand Prize at UC San Diego's Triton Innovation Challenge.

For more information, visit greenwaterscientific.com.

Notes to editors: The full NABL test report and high-resolution product images are available on request.