Smog tower’s current eﬃciency ‘half’ of Delhi Government claim
- The smog tower at Connaught Place, a pilot project installed at a cost of ₹20 crore, was inaugurated on August 23 by Chief Minister Arvind Kejriwal, who had said similar towers will be built in other parts of the city if the results are satisfactory.
- However, two months later, the percentage of pollution being reduced is only 34%-43%, according to six readings between November 30 and December 1.
Smog Tower :
- A smog tower is a structure designed to work as a large-scale air purifier.
How it works?
- This structure fitted with multiple layers of filters which trap fine dust particles suspended in the air as it passes through them.
- Air is drawn through fans installed at the top of the tower, passed through filters, and then released near the ground.
Are they helpful?
- Yes, smog towers have been experimented with in recent years in cities in the Netherlands, China, South Korea and Poland.
- The first such tower was erected in 2015, in Rotterdam, Netherlands (it can filter 30,000 cubic metres of air per hour around it).
- Experts have said that the towers would create “clean air zones” in the city.
- A tower would reduce 50% of the particulate matter load — fine dust particles suspended in the air — in an area of 1 kilometre in the direction of the wind, as well as 200 metres each along the sides of the tower and against the direction of the wind.
Why Delhi needs such measures?
- Air pollution in the national capital has been an issue of concern for quite some time as Delhi and its suburbs have ranked among the most polluted cities in the world frequently since 2014, when the World Health Organisation (WHO) declared Delhi the most polluted city in the world.
- Pollution levels in Delhi increase dramatically during winter — on some days to nearly 10 times above the limits prescribed by WHO, posing a serious risk to vulnerable and also healthy populations.
Other Measures taken to control pollution:
- Persuading farmers in Punjab and Haryana to use mechanical alternatives to stubble-burning.
- Closure of thermal power stations in Delhi.
- Making industries use piped natural gas.
- Control measures taken under the Graded Response Action Plan (GRAP) when pollution levels spike.