New Delhi, India
As the Indian Capital, Delhi, suffocates under a blanket of smog blamed on stubble burning, a new study has revealed that thermal power plants emit 16 times more pollution.
The study by the Centre for Research on Energy and Clean Air (CREA) has revealed coal-fired thermal power plants in the National Capital Region (NCR) produce 16 times more air pollutants than stubble burning.
The scale of emissions
Between June 2022 and May 2023, NCR thermal power plants released 281 kilotonnes of sulphur dioxide (SO2), while the burning of 8.9 million tonnes of paddy straw contributed just 17.8 kilotonnes of SO2.
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"A comparison between NCR thermal power plant emissions and paddy straw burning emissions in Punjab and Haryana highlights the scale of SO2 pollution. Thermal power plants in NCR emit 281 kilotonnes of SO2 annually—16 times more than the 17.8 kilotonnes emitted by burning 8.9 million tonnes of paddy straw," notes the study.
The report notes that thermal power plants are a "year-round" pollution source.
"While paddy straw burning causes seasonal spikes, thermal power plants represent a larger, persistent pollution source year-round, underscoring the need for stricter controls on thermal power plant emissions. Yet, thermal power plants often receive leniency and repeated compliance extensions, especially for installing FGDs, whereas stubble burning is heavily penalised, with strict enforcement on farmers during the burning season."
What can be done?
The CREA study highlights the potential of flue gas desulfurisation (FGD) technology to reduce emissions by 67 per cent, bringing SO2 levels in NCR thermal plants down to 93 kilotonnes annually.
"Over 96 per cent of particulate pollution from coal-fired power plants in the NCR is secondary in nature, primarily originating from SO2. Reducing SO2 emissions can significantly decrease the secondary particulate matter load, thereby reducing the health risks associated with prolonged exposure to these particles," explained Manoj Kumar, an analyst at CREA.
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"SO2 levels often meet the NAAQS because, once released, it quickly transforms into sulfates—secondary particles that are major components of PM2.5. These secondary particles have a longer lifetime and pose serious health risks. This hidden transformation of SO2 into harmful particles emphasises the necessity for FGD installation," he added.
While thermal plants are a significant source of pollution, vehicular emissions accounted for 15.8 per cent of Delhi’s pollution on Sunday, according to the government’s Decision Support System for Air Quality Management. Meanwhile, stubble burning spiked on Saturday, contributing 25 per cent of the city's pollution.
(With inputs from agencies)