Delhi Teen Krish Aggarwal Wins Diana Award 2026 for Low-Cost Fan Air Purifier (₹140)

The news

A Delhi school student has won the 2026 Diana Award for a low-cost air purifier that attaches to a ceiling fan and costs just ₹140 to make. Krish Aggarwal, a student of Sanskriti School in New Delhi, co-founded Project Vayu with his classmate Samarth Meetal. The award, given in memory of Britain's Princess Diana, honours 198 young changemakers from 44 countries this year. Krish is among them.

The filter uses electrostatically charged fibres that trap fine particles, including PM2.5, as the fan runs. When the fan is switched on, the filter inflates like a balloon, increasing the surface area for air purification. The team claims that in a closed-room test, PM2.5 levels dropped by over 90% in one hour — from 158 micrograms per cubic metre to 11. The filter is provided free to schools and is replaced every month.

Project Vayu has installed 602 filters across 295 classrooms in Delhi, benefiting about 8,000 children. The Diana Award page states that over 10,000 students have benefited overall. Most filters have gone to under-resourced schools. The team is now preparing to supply filters to 45 more schools in Delhi.

What is the Diana Award and when did it begin?

The Diana Award was established in 1999 in memory of Diana, Princess of Wales, who died in 1997. It is a UK-based charity that recognises young people aged 9 to 25 for their social action or humanitarian work. The award is given in two main streams: the Diana Award for young changemakers and the Legacy Award, which is presented every two years. It is not a state honour but a charitable initiative, though it carries significant global prestige. The award operates independently of the British royal family and is supported by a board of trustees. Recipients are nominated by adults and assessed on the impact and sustainability of their work.

How does the fan filter work?

The filter is designed to be attached directly to an existing ceiling fan in a classroom. It contains electrostatically charged fibres that attract and trap fine particles such as PM2.5, which can penetrate deep into the lungs. As the fan rotates, the filter inflates, increasing the surface area for filtration while allowing air to pass through easily. No separate machine or technical expertise is required.

What has the project achieved and what are its limits?

Project Vayu has demonstrated a frugal innovation that repurposes existing infrastructure at a cost of ₹140 per filter, provided free to schools. The team's own test showed a PM2.5 reduction from 158 to 11 µg/m³ in one hour, a drop of over 90%. However, this claim has not been independently verified by a third party. The project has reached over 10,000 students, mostly in under-resourced schools, but scaling up would require funding for mass production and partnerships with municipal bodies.

What is the next step for Project Vayu?

The team is preparing to supply filters to 45 more schools in Delhi. Krish Aggarwal has also advocated for youth voices to be heard in climate-related decisions, pointing to a broader role for student-led environmental action beyond the filter itself.