IISc tech powers a clean-air upgrade on ACs

Bengaluru: Germ-killing filters developed at the Indian Institute of Science (IISc) in late 2022 are powering a commercial product that supplements air-conditioners to generate cleaner air.

Designers of the AIRTH air purifier pitch it as a sustainable alternative to traditional AC mesh filters that offer no defence against invisible pollutants and expensive stand-alone purifiers that consume large amounts of electricity. The purifier does not run on electricity and works sitting atop the AC unit.

The antimicrobial HEPA (high efficiency particulate air) filters in the purifier trap dust and eliminate germs, and delivers clean air into the AC. It sets up a barrier against microbes without impacting the airflow into the AC. The active ingredients in the filters are compounds extracted from green tea that offer a surface that inactivates microbes, including viruses.

Developed in association with AIRTH, a startup incubated at IIT-Kanpur, the air purifier now has a presence in over 10,000 homes, the team which developed the product said.

Ravi Kaushik, IIT-Bombay alumnus and founder-CEO, AIRTH, said the technology enhanced the air quality and reduced the maintenance burden on AC units. Delhi-based AIRTH works on clean air solutions with technologies developed at IIT-Kanpur, IIT-Bombay and IISc.

Prof Suryasarathi Bose from the Department of Materials Engineering in IISc said the air purifier presented an affordable upgrade for better health.

Germs captured on traditional air filters, over time, lower the filters’ efficiency and can cause infections to the users. The team noted how the summer could set off mass AC usage, even as the quality of indoor air and its impact on respiratory health — especially of the elderly and people with conditions like asthma or allergies — remained largely overlooked.

Tests on the technology done at premier laboratories have found 90% reduction in harmful sub-micron air pollutants and PM 2.5, and that the filter was effective against the SARS-CoV-2 virus. The air purifier is priced Rs 2,500.

“The product has undergone rigorous testing in accredited labs, demonstrating up to 99.9% efficiency in reducing the viral load. This environment-friendly solution represents a significant advancement in indoor air purification,” Prof Bose said.