Almost exactly one year after a scientific paper in respected international peer-reviewed open access journal Atmosphere stated in no uncertain terms that smog towers do not work for cleaning outdoor air, two giant, 24-metre-high 40-fan piece of equipment that claims to do just that have come up in the capital city, an ode to the politicisation of India’s air pollution.

Built by Tata Projects Ltd in consultation with the NBCC Ltd, based on a patented design owned by the University of Minnesota under the reluctant supervision of IIT Bombay, the first one was inaugurated in Connaught Place with great fanfare by Delhi chief minister Arvind Kejriwal on August 23, triggering a war of words between the Bharatiya Janata Party and Kejriwal’s Aam Aadmi Party, with both trying to take credit for the “first” smog tower in Delhi.

Not to be left behind and using the occasion of the United Nations-designated International Day of Clean Air for Blue Skies on September 7, Union Environment Minister Bhupender Yadav of the BJP inaugurated the second tower exactly a fortnight later in East Delhi’s even more polluted Anand Vihar area.

Unscientific and inefficient

Neither party has paid attention to the fact that no impact assessment study was done before setting up the towers, no reputable scientists have come out in support of smog towers as an efficient way to curb pollution and no other country in the world has managed to clean outdoor air with the help of giant purifiers. In fact, environmentalists, scientists and clean air advocates have publicly and consistently opposed such measures.

These completely unscientific and inefficient towers are a result of a Supreme Court decision in November 2019 directing the government to install “smog towers” in Delhi, which independent scientists have called an injudicious move and a waste of public money. Both the giant pieces of useless equipment are paid for by taxpayers funds, and together cost the exchequer roughly Rs 40 crore, a significant amount that could have been better utilised in reducing emissions at source.

This money could have gone towards implementing clean energy and clean air solutions such as providing LPG and electricity for all cooking and heating purposes, increasing energy efficiency in industries, promoting renewable energy sources, improving waste management, reducing open waste burning, developing public transport and walking and cycling infrastructure, just to name a few.

Smog towers are red herrings. They are attractive to governments because they are visible, a physical manifestation of the government’s fight against air pollution – making it look like governments are actually “doing something” to clean the air. Such installations give citizens a false sense of complacency and assurance, making them feel they are getting air of better quality. This false belief not just encourages polluting behaviour, but because smog towers impose no costs on polluters (thus not antagonising any interest groups) they are populist, thus making it very difficult to oppose in spite of the science and evidence pointing clearly to their ineffectiveness.

A technological path to clean air without anybody having to change their polluting behaviours may seem like a win-win – and the image of a giant vacuum cleaner sucking in dirty air and releasing clean air is alluring. But since that “technology” includes thousands of physical filters (these smog towers have 10,000 between the two), they actually end up adding to the pollution, as clogged filters find their way to our already overburdened landfills and end up being burnt. Science tells us that these don’t end up cleaning even a fraction of the air. So why isn’t this issue laid to rest once and for all?

The reason is that cleaning the air the right way – i.e. by reducing emissions at source – requires strong, unpopular measures that penalise polluters and reduce their profits either by internalising cleaning costs (think thermal plants which have been resisting installing flue gas desulphurisation filters in chimneys because they come at a cost) or by imposing fines (which polluters choose as the preferred route since fines aren’t nearly high enough to make polluting behaviours unprofitable.)

Populist measure

Politicians are driven mainly by populist measures and lobby groups usually take care of the misleading communications (and often, share some of the extra profits to sidestep enforcement). Unfortunately, it is communications like these that influence even the most well-intentioned of judges to make misguided judgements, as outlined later in this article.

Additionally, emission reduction measures don’t make for the sort of photo-ops politicians thrive on, such as the inaugurations of inefficient towers or planting drives of saplings that are often left to die once the media has left. As a case in point – even after the grand inauguration, the current towers are not even functional. The 5,000 filters of each have still not been installed (as the humidity in the air currently will ruin them) and without the filters, there is no point running the fans.

If Delhi Chief Minister Arvind Kejriwal hadn’t been an alumni of the prestigious Indian Institute of Technology, one could have written off all the credit-seeking around the inauguration of this towers as a politician’s folly. But given his background, it is clear that he knows how ineffective these measures are and he is merely playing the game of one-upmanship.

In this context, his statement that “this smog tower has been made with American technology and will reduce the amount of pollution in the air” is disturbing. Even more disturbing is that he indicates that this project “will be replicated”.

As for the BJP, the less said, the better. Its party member Gautam Gambhir has already demonstrated his lack of scientific knowledge by setting up a smaller smog tower (on public land) in Delhi’s Lajpat Nagar market. A Right to Information request filed to get impact assessment information on Gambhir’s tower made it clear that there was no scientific basis to these measures. The reply to four specific questions asking for details (existing or planned impact assessment reports, names of stakeholders, feedback) got just one answer: “No such information available.”

Even if this tower was set up with Gambhir’s political or parliamentary funds (or even his personal money), the tower is on public land and we, the public, need answers about why this has been allowed. In addition to using public land, public electricity, dumping used filters and the collected soot, carbon and dust on public grounds or overflowing landfills (which quickly finds its way back into the air), this sort of thing diverts attention from real solutions like reducing or capturing emissions at source.

What has been intriguing in the complete lack of a single scientist or air pollution researcher validating the efficacy of smog towers. Even in the Delhi government’s press release, the only validation given is from “IIT Bombay”, a singularly nebulous term, with no scientist quoted by name. There have been some bold enough to speak out against these useless towers. Such scientists realise the importance of communicating their science and research.

But most others, true to form, are too wrapped up in their research to step out of their silos to communicate and spread awareness. Additionally, they want to steer clear of any controversy. Most like to keep a low profile, especially if their research is funded by government grants. After all, who will want to bite the hand that feeds it? This is especially true of atmospheric scientists associated with the IITs.

This is why it is especially important to allow independent scientists and citizen scientists access to all technical details of this new, grand smog tower, as well as access to the Air Quality Index numbers around this area.

Public money

But why is it important for us to continue questioning the installation of smog towers? Well, of course firstly because they are unscientific and inefficient. But even more importantly, because these are paid for by public money – our taxes – and we don’t want more of these useless towers to come up. If someone wants to install giant purifiers at a high private cost (as the American Embassy School once considered doing), it is their decision. Spending private money on foolish measures is a private decision. But spending scarce tax-money on populist measures not backed by science is unforgivable.

Outdoor purifiers paid for by public money aren’t new. Some of those which came up earlier have quickly turned into expensive spittoons and dustbins, not just in Delhi but also Bangalore and other cities.

So despite so many failed attempts, let us try and understand why this issue won’t die – and what we as alert citizens can do to stop such wasteful expenditure.

To understand this, we must first consider the background: in November 2019, just before the Covid-19 pandemic was fluttering to life, the Supreme Court of India, worried about the ongoing public health emergency triggered by India’s filthy air, directed the Delhi government to install smog towers to bring down high levels of pollution that was enveloping Delhi and National Capital Region in its annual deathly shroud.

Its strong words expressed an almost enraged concern over a city that turns into a gas chamber every winter, and it was clear that the court was looking desperately for solutions. But judges aren’t atmospheric scientists or subject experts. Although well-intentioned, the direction was faulty.

There was an immediate, almost unanimous outcry among clean air activists and air pollution experts. Within days, Care for Air, the non-profit that I co-founded, wrote an open letter to the court pointing out the folly of such an unscientific order, detailing the inefficiency of such expensive, giant outdoor purifiers.

Atmospheric scientist and Care for Air adviser Dr Sarath Guttikunda, carefully unpacked the science behind why such giant air purifiers don’t work, a precursor to the paper published eight months later. “Resources for environmental protection are scarce. Why spend it on ineffective band-aids?,” the letter pleaded. “Air pollution, specifically the more lethal PM2.5 particulate matter can only be controlled by eliminating emissions at all known sources. Any other way is bound to be inefficient, ineffective and unscientific, and can only buy time – but which we are paying with our breaths every day.”

The letter quoted one of the organisation’s international advisers, Josh Apte, criticising giant purifiers by saying “Many professors assign this as homework or exam problems to explore why this approach simply cannot work at scale.”

Contempt action threatened

Subsequently, and significantly, IIT-Bombay withdrew from this project. This is significant because it clearly indicated the lack of belief in the efficacy of such towers by experts, technologists, scientists and engineers at India’s premier institute of technology. This should have stopped the court on its tracks. Instead, it threatened contempt action against the government-funded institute, bringing it scurrying back into a project it didn’t believe in.

At this point, in August 2020, Care for Air filed a plea to reconsider the Supreme Court order to set up towers in public interest, which was dismissed without a proper hearing, despite the PIL annexing the scientific paper published in Atmosphere that demonstrated in no uncertain terms that smog towers are inefficient.

Says Guttikunda, one of the writers of the paper:

 “The best engineering solution to control air pollution is by controlling the emissions at the sources. For example, we can control the emissions in vehicle exhaust by using filters for particles and catalytic converters for gases. This is straightforward because exhaust has only one exit point. But, when you look at a city – it is vibrant with no borders and emissions coming from a million vehicles, a million households, and a million other activities, and sometimes not even from its own boundary. In an environment like this, thinking that a vacuum cleaner will help solve a city’s air pollution problem and magically suck away the emissions is not only un-engineering, un-scientific, but also foolish.”

The two new smog towers are supposed to purify 1,000 cubic metres of air per second, which experts have previously said is like filling a bucket with a hole.

“When judges decide to act as scientists, they can still demand compliance, but it spells disaster,” lawyer Veera Mauli wrote in the Indian Express after the dismissal of the Public Interest Litigation. “This awaiting disaster is coming at the huge cost of taxpayers’ money, which can be otherwise used for more practical, effective and evidence-based solutions against air pollution. It is not within the mandate of the Supreme Court to deem such an exercise to be strategically, scientifically and financially wise, and direct compliance. There is no justification, in law, or in fact for the court to have directed the undertaking of this project.”

A year after the court’s dismissal of the please, the two giant towers stand tall as an ode to impractical, inefficient solutions and the politicisation of Delhi’s air.

As a vigilant citizen scientist who has studied air pollution research and its health harm for seven years, I have two specific requests:

1) The government should install calibrated continuous air quality monitors within a 1 km radius of these towers to allow the public to oversee the efficacy and efficiency of this tower. Any pollution data collected around this publicly funded tower on public land should be transparent and made freely accessible to the public.

2) Not a single more smog tower should be allowed on public land with public funds until the two-year study the government has said will be carried out with these two towers has been completed and shared in public domain and scrutinised by independent scientists – scientists whose research isn’t funded by the government or financed by the makers of these smog towers.

Otherwise, this ode will fast turn into an elegy for Delhi residents.

Jyoti Pande Lavakare is an independent journalist, co-founder of clean air non-profit Care for Air and the author of grief memoir “Breathing Here is Injurious to Your Health: The Human Cost of Air Pollution,” published by Hachette in November 2020