The inaugural ceremony of India’s first ever smog tower, located in Connaught Place (CP), New Delhi, was recently initiated by the Chief Minister. This launch was conducted well ahead of a typical surge in pollution levels in the city, primarily caused by crop waste combustion, or stubble burning, by farmers.
A Look Back at the Genesis of Smog Towers
This innovative project was spurred by the Supreme Court in 2019 when it ordered the Central Pollution Control Board (CPCB) and the Delhi government to develop a plan to install smog towers as a solution against the widespread air pollution. A proposal for the implementation of these towers was submitted by IIT-Bombay to CPCB. In 2020, the Supreme Court further directed that two such towers should be constructed as part of an exploratory project by April. The CP tower is one of these, with the other one at Anand Vihar in east Delhi nearing completion, supervised by CPCB.
About Smog Towers: A General Overview
Smog towers are engineered to act as large air purifiers. These structures are often equipped with multiple layers of air filtration systems. As polluted air passes through these filters, contaminants get removed. The world’s largest smog tower is in China.
Technical Specifics of the Tower
This smog tower utilises a ‘downdraft air cleaning system’. Under this system, contaminated air is drawn in from a height of 24 metres. After filtration, clean air is released close to ground level, about 10 metres up. This differs from the Chinese model that employs an ‘updraft’ system, propelled by heat and convection, where air is gathered near the ground and released at its apex.
Key Contributors
Tata Projects Limited built the tower with technical insights from IIT-Bombay and IIT-Delhi, who will also evaluate the project’s data. The National Biofuel Coordination Committee (NBCC) India Ltd functioned as project management consultants, while the Delhi Pollution Control Committee was responsible for managing the project.
The Dire Need for Pollution Control
The CPCB reported that PM10 levels in Delhi have skyrocketed by 258% – 335% since 2009. However, PM2.5 is the dominant pollutant in Delhi and surrounding regions. These microscopic particles penetrate deeply into the respiratory system, potentially inducing lung inflammation and other cardiovascular and respiratory issues. For the third year running, Delhi was named the most polluted global capital in 2020 according to a Swiss group’s report.
Potential Limitations of Smog Towers
Despite offering immediate respite from pollution within a limited area, smog towers are expensive and lack scientific evidence confirming their long-term efficiency. The tower’s influence on air quality may extend up to a kilometre from its base. However, IIT-Bombay and IIT-Delhi will conduct a two-year study to gauge the actual impact, testing different weather conditions and analysing variations in PM2.5 levels with air flow.
Further Steps Counteracting Pollution in Delhi
Subsidies for farmers to purchase Turbo Happy Seeder (THS), which reduces stubble burning, the introduction of BS-VI vehicles, encouragement for electric vehicles (EVs), emergency measures like Odd-Even, construction of Eastern and Western Peripheral Expressways to decrease vehicular emission, execution of the Graded Response Action Plan (GRAP), use of green firecrackers, and the development of the National Air Quality Index (AQI) for public information under CPCB control, have all been initiated.
The Road Ahead
With no compelling scientific validation supporting smog towers’ efficacy, it is peremptory that root causes are addressed. Governments need to encourage renewable energy usage to combat air pollution and reduce emissions. It would be regrettable if other cities felt compelled to follow Delhi’s example, thereby installing expensive, potentially ineffective towers.