India's first air tower based on microalgae has been set up in New Delhi to cut vehicular air pollution. Installed near the Aerocity highway as a pilot project, it is testing a new approach to pollution control. The tower draws in polluted air and uses microalgae and photosynthesis to absorb pollutants such as carbon dioxide, nitrogen oxides and particulate matter, converting them naturally into oxygen and algal biomass. The project represents a nature-based and sustainable way to improve air quality in cities.