Coal-based thermal power plants worsening Delhi air pollution, says new study

A new suggests that coal-based thermal power plants are responsible for aggravating air pollution in Delhi-NCR, as most of them are not complying with emission control norms. Delhi-NCR has 11 thermal power plants. An analysis by the Centre for Science and Environment (CSE) revealed that the thermal power plants contribute around 8 per cent of particulate matter (PM) to the air in Delhi-NCR.

Anumita Roychowdhury, Executive Director, of Research and Advocacy, CSE, said in a press release, "Delhi and NCR cannot meet the clean air benchmark and protect public health if the continuous sources of pollution like thermal power plants remain high emitters."

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Roychowdhury said that these plants have not been able to meet the standards and "are at varying stages of progress simply because the target dates for compliance (with emission control norms) are shifting continually".

The recent study by the environmental think tank focused on particulate matter, nitrogen oxide and sulphur dioxide emissions from the 11 thermal power plants (TPPs) in Delhi-NCR.

The analysis was based on the environmental status reports of these plants accessed from the website of the Central Electricity Authority (CEA), a technical arm of the Union Ministry of Power, from April 2022 to August 2023.

The study revealed that "only two of 11 plants in NCR have sulphur dioxide (SO2) control measures in place" and "only one meets the SO2 emission standards".

Meeting the norms for emissions

The CSE report said that despite multiple deadline extensions and revised categorisations by the Union Environment Ministry, many plants in the region are struggling to meet prescribed norms for emissions of nitrogen oxide, sulphur dioxide and particulate matter.

The ministry established stringent emission standards for coal-based power plants in December 2015, requiring compliance within two years. "Since then, the norms have been diluted for several parameters and deadlines have been repeatedly delayed," the report said.

Later, it granted a five-year extension to all power plants, except those in Delhi-NCR which were given until 2019 to comply due to the region's high pollution levels.

Despite this, except for Dadri TPP and Mahatma Gandhi TPP, all NCR plants failed to meet the revised deadline and continued operating in violation until another extension in March 2021, the CSE report added.

Now, it was at this time that the ministry classified all power plants, including the ones in NCR, under three different categories: A, B and C. The categorisation was based on the criteria defined by the Central Pollution Control Board (CPCB).

According to the new deadlines:

> Category A plants can meet SO2 emission norms by December 31, 2024.

> Category B plants can meet SO2 emission norms by December 31, 2025.

> Category C plants can meet SO2 emission norms by December 31, 2026.

Roychowdhury said that instead of delaying the timeline, more focus should be laid on the enablers in terms of strong compliance and deterrence mechanisms as well as incentives and one-time support for fast-tracking change and for time-bound implementation.

Key findings of the CSE report

1. Three plants in the NCR — Harduaganj thermal power station of UPRVUNL, Panipat Thermal Power Plant of HPGCL, and Guru Hargobind TPP (Lehra Mohabbat) of PSPCL — are reporting very high suspended particulate matter emissions.

2. Despite the relaxation in norms and deadlines, four plants — Panipat TPS, Rajiv Gandhi TPP and Yamunanagar TPP in Haryana and Guru Hargobind TPP (Lehra Mohabbat) in Punjab — have exceeded the Nitrogen oxide norms several times during the reporting period. (Three in Haryana, one in Punjab)

3. In the case of sulphur dioxide, the Mahatma Gandhi TPP is the only power plant in NCR where the norms are within the prescribed limit.

4. Dadri TPP is another plant that has sulphur dioxide control equipment (FGD) in place, but the plant has reported high sulphur dioxide readings 86 per cent of the time during the reporting period.

5. All the coal power plants in NCR have reported sulphur dioxide emissions up to three times over the prescribed limits.

Why is sulphur dioxide a concern?

According to DD Basu, Former Director, Central Pollution Control Board (CPCB), said, “Sulphur dioxide is a reactive gas and converts to sulphates in the form of fine particulate matter -- PM2.5 -- which poses even a greater risk to health and environment. Therefore, control of sulphur dioxide is crucial from the perspective of controlling particulate matter emissions.”

Nivit Yadav, Programme Director, Industrial Pollution, CSE, said, "The plants may not be in violation of the 2015 notification due to the extended deadlines granted to them to comply with the norms, but such high emissions of PM, nitrogen oxide and sulphur dioxide will only worsen the pollution in NCR.”

Delhi's air quality remained 'very poor' on Sunday though a change in meteorological conditions due to a western disturbance may bring some relief, according to monitoring agencies.

Meanwhile, Delhi Environment Minister Gopal Rai on Sunday expressed hope that the air quality would continue to improve for the next two days owing to an increase in wind speed and probability of rain.