Air pollution in North India has assumed unprecedented proportions, making international news of late when the Air Quality Index (AQI) hit the record high of 1,500. While it is increasingly well accepted that seasonal burning of paddy crop residue has been a major source of this pollution, thermal power plants remain an order of magnitude larger and substantially more consistent pollutants. Despite their continuous emissions and considerable health and environmental impacts, the enforcement of regulations on these plants remains insufficient.
The Indo-Gangetic Plain experiences severe pollution in winter due to a combination of stubble burning, lower temperatures, and stagnant winds. This results in a thick curtain of smog laden with PM2.5 particles—fine, toxic pollutants that arise from fuel combustion and biomass burning. However, according to an analysis by the Centre for Research on Energy and Clean Air (CREA), thermal power plants emit 10 times more PM2.5 and over 200 times more sulfur dioxide annually than crop residue burning. Sulfur dioxide emissions in the National Capital Region (NCR) are 16 times higher from thermal power plants than from stubble burning.
Despite the obvious damage caused by emissions from thermal power plants, the regulatory focus on them is comparatively weak. Technologies like flue gas desulfurization (FGD), which filter out sulfur dioxide, are scientifically proven to significantly reduce pollution. Yet, their implementation remains slow and fraught with delays. The Ministry of Power has also recently applied for an extension to install FGD systems, and the NITI Aayog has even suggested bypassing these technologies. Such mixed signals from authorities embolden the power plant operators to delay the compliance of emission norms.
The first compliance date for installing FGDs will be on December 31, 2024, for those plants falling within a 10-kilometer radius of Delhi NCR. However, an analysis at CREA reveals that only one out of four plants in this category have complied fully so far. India’s dependency on coal has been one of the major reasons why progress in this regard is lagging. 47% of electricity generation capacity happens through coal-based power plants, but it meets over 70% of the country’s power demand. This reliance on coal has resulted in India emerging as the largest emitter of sulfur dioxide globally and accounted for 16% of global emissions in 2022. The estimated sulfur dioxide emitted by thermal power plants between June 2022 and May 2023 is about 4,327 kilotonnes.
With the help of FGD technology, sulfur dioxide can be reduced from 4,327 kilotonnes to 1,547 kilotonnes, that is, by about 64%. Its use may also avoid the formation of secondary particles such as sulfate aerosols, which are among the significant contributors to the PM2.5 concentrations. According to Indian Institute of Technology, Delhi, and the Central Electricity Authority, researches prove that FGDs reduce sulfur dioxide levels considerably up to a 60-80 km radius from the power plants. Yet, of India’s 600 thermal power plants, only 44 have installed FGD systems. Tenders to install FGD on 233 more have already been awarded.
Emission standards for thermal power plants were initiated by India back in 2015, asking thermal power plants to install FGD by the end of December 2017. The deadlines were extended since then. The latest notification requires Category A plants—those near Delhi NCR or cities with populations exceeding one million—to comply by December 31, 2024. Plants in “critically polluted areas” (Category B) have a deadline of December 31, 2025, while others must comply by December 31, 2026. Non-compliance will result in penalties ranging from ₹0.2 to ₹0.4 per unit of electricity generated. However, meeting these deadlines seems unlikely since the Ministry of Power recently proposed a 36-month extension citing limited domestic manufacturing capacity, import dependency, and growing demand.
Experts have criticized the repeated delays saying that FGD technology is neither new nor inaccessible. Ashwini Chitnis of the Centre for Social and Economic Progress notes that the constraints cited by the government remain unchanged for the last decade. She points out that the country is known to import other equipment regularly, like solar panels, and sees no reason it cannot import FGDs as well. India’s lax approach to enforcement and urgency in setting up FGDs hampers efforts in the fight against air pollution as millions continue to be exposed to its ill effects.
While India has pledged globally to phase down unabated coal power, domestic action speaks otherwise. Controlling industrial emissions has less than 1% of funds allocated in clean air programs. Hence, pollution control from thermal power plants needs to be addressed on an urgent basis and with great emphasis. If FGD systems are not strictly complied with and implemented in a timely manner, the health and environmental costs of coal-fired power generation will keep increasing.