Delhi funds projects to cleanse its toxic air

But more policies are needed to transition the city to renewable energy, say researchers.

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A street cleaner works in heavy smog in Delhi

Delhi's government has announced initiatives to cut air pollution.Caption: Cathal McNaughton/Reuters

The government of Delhi — the world’s most polluted megacity — has proposed 26 new programmes to clean up its notoriously smoggy air, but several researchers and policy experts say that the actions don’t go far enough.

The city included the anti-pollution initiatives as part of the Delhi government’s 530 billion Indian rupees (US$8.2 billion) budget for 2018-2019, released on 22 March. The government is promoting part of the funds as “a green budget” - but it’s unclear how much will go to specific initiatives, say policy experts. “It would have been better had the government made a separate financial provision for the green budget, rather than merely a lump-sum budgetary provision for all the schemes, programmes and capital projects,” says B. K. Chaturvedi, a former cabinet secretary who has managed many energy and environment programmes.

The anti-pollution initiatives include 1,000 fully electric buses; further subsidies on electric vehicles; tree planting; incentives for restaurants to replace coal-fired ovens with electric or gas-powered ovens; and programmes to replace diesel generators with cleaner-fuel equivalents and street lamps with light-emitting diodes (LEDs). To increase renewable energy consumption, the city will also offer incentives to households and farms that install solar panels.

Delhi has drawn attention for its consistent ranking among the most-polluted cities globally. Delhi’s chief minister, Arvind Kejriwal, likened the city to “a gas chamber” in a tweet posted in November last year; on the same day, the Indian Medical Association called the city’s smog a “public health emergency”.

Tackling knowledge gaps

The latest budget also announced several international collaborations to improve scientific and technical expertise of the institutions responsible for controlling air pollution. The government will carry out a greenhouse-gas inventory exercise in partnership with C40 Cities Climate Leadership Group, a network of more than 90 major cities tackling climate change. The city has proposed building an air-pollution forecasting model, consulting with the World Bank. Delhi will also be the first Indian city to conduct a study on sources of pollution in real-time, working with the University of Washington in Seattle.

The main sources of the city’s toxic air are vehicle emissions, crop and wood burning and dust from roads and construction sites. A 2016 study1of Delhi’s air by the Indian Institute of Technology, Kanpur, found that road dust constitutes about 38% of fine matter called PM2.5 — particles 2.5 micrometres or smaller in diameter and the most dangerous type to human health.

Renewable-energy specialist Mark Jacobson at Stanford University in California says that the new initiatives are a step in the right direction, but it would have been better had the government focused on transitioning the city to clean, renewable energy, rather than studying the causes of air pollution, which are already well known.

Bharati Chaturvedi, director of the Chintan Environmental Research and Action Group in New Delhi, is concerned that the budget does not deal sufficiently with the dust, which is also a major source of pollution from PM10 — particles whose diameters are 10 micrometres or less. “Dust control is a low priority, but it should be a high priority,” she says. Chaturvedi advocates for installing water-spraying machines at locations of substantial dust pollution, such as construction sites and traffic lanes. “If big builders do not buy them, then for our sake, the government needs to,” she says.

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  1. 1.

    Sharma, M. & Dikshit, O. Comprehensive Study on Air Pollution and Green House Gases (GHGs) in Delhi (Indian Institute of Technology, 2016); available at

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