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India is at the Energy Crossroads and Must Clean Up its Coal Act

India’s complicated love affair with coal is no secret. As the world’s third-largest carbon emitter, the country is under immense pressure—both domestic and global—to reduce its carbon footprint. Yet coal remains the cornerstone of India’s energy matrix, powering over 70% of its electricity generation. The question isn’t whether India can wish away coal—it’s how it can make coal cleaner while pursuing economic growth and energy security. At a recent event hosted by the Centre for Science and Environment, Ashok Lavasa, a former secretary to key union ministries, captured this nuance aptly: “If coal is king, can it be a benevolent king?” The answer lies not in utopian ideals but in pragmatic solutions that blend energy reliability with environmental responsibility. Coal’s Staying Power—and Its Environmental Cost Electricity demand in India is soaring. From 2021 to 2025 alone, it jumped by over 9%, with forecasts suggesting it could double by 2030. Renewable energy is growing too—currently making up 46% of installed capacity—but its intermittency limits its ability to meet peak demand, especially at night. Thermal power plants offer grid stability and continuous supply, but at a steep environmental cost. More than 40% of India’s annual carbon emissions stem from electricity generation, with coal being the main culprit. While the net-zero target by 2070 remains firm, the route to get there is complicated. Can We Burn Coal Without Burning the Planet? The answer may not lie in phasing out coal entirely, but in innovating how it’s used. A recent CSE report suggests decarbonising thermal plants could slash emissions by up to 30%. One proposal includes reducing the minimum operational threshold of these plants from 55%—a level often maintained even when renewable power is available—to lower figures, enabling more dynamic balancing with green sources. Another option is to increase the use of agricultural residue in place of coal. This has already led to measurable reductions in Delhi and surrounding areas, though adoption elsewhere remains minimal. Technologies that capture carbon dioxide emissions are also being explored but currently capture only about 0.1% of global emissions. The path to cleaner coal, however, is paved with costs and uncertainties. Upgrading existing infrastructure, adopting new technology, and training operators require substantial capital and policy commitment. And the million-dollar question remains—who pays for all this? Policy Steps Forward—or a Step Backward? In a controversial move, India recently exempted 78% of its thermal power plants from installing flue gas desulphurisation (FGD) systems, which are vital for controlling sulphur dioxide (SO₂) emissions. These emissions contribute to fine particulate matter, which causes respiratory and cardiovascular diseases. The Ministry’s rationale is based on low current SO₂ levels and the assumption that Indian coal has lower sulphur content. Experts argue otherwise. Studies show that thermal plants can impact air quality up to 200 kilometers away, and simply using taller chimneys disperses pollutants without eliminating them. With just 8% of plants having installed FGD units so far, this rollback of environmental safeguards could affect millions. A Glimmer of Strategic Innovation There is a silver lining. The government is exploring the conversion of 10 retired thermal power plants into nuclear power stations. These sites already have much of the necessary infrastructure and offer a low-carbon pathway to help meet India’s goal of 100 GW nuclear capacity by 2047. If implemented carefully—keeping in mind seismic stability, water access, and population proximity—this could be a transformative step. India’s journey toward a cleaner energy future is not a linear one. Coal will remain part of the equation for decades to come. But it’s what India does in the meantime—how it makes coal cleaner, invests in energy storage, balances grid stability, and builds trust with its people and the planet—that will define its leadership in the energy transition. The king isn’t going anywhere just yet. But with the right reforms, it just might learn to rule with a lighter, greener touch.

India crosses 50% non-fossil power capacity target under Paris Agreement: Cabinet

“As a commitment made to the Paris Agreement, the achievement of India’s NDC target is commendable and signals its intent to diversify its energy mix whilst continuing to tackle growing power demand. Having achieved this, all efforts must now be directed to raise the actual share of generation from renewables (combined with storage) in the power mix—which currently stands at 13% for solar and wind—to displace coal,” programme manager for climate change at the Centre for Science and Environment, Avantika Goswami, said. India has surpassed its target of installing 50% of its power capacity from non-fossil fuel sources, achieving a key nationally determined contribution (NDC) under the Paris Agreement five years ahead of the 2030 target, the Union Cabinet said on Wednesday. “India’s achievement of 50% non-fossil fuel installed capacity ahead of the target year is a testament to its ambition, innovation, and commitment to sustainable development. It affirms that development and decarbonisation are not contradictory goals, but can in fact reinforce each other. As the country moves toward the goal of 500 GW of non-fossil capacity by 2030 and net-zero emissions by 2070, the path forward must be bold, inclusive, and technology-driven,” union minister of new and renewable energy Pralhad Joshi said on July 14. India’s updated NDCs under the Paris Agreement, submitted in August 2022, said that the country aims to reduce the emissions intensity of its gross domestic product (GDP) by 45% by 2030 from 2005 levels; increase the share of non-fossil fuel-based energy resources to 50% of its installed power generation capacity by 2030; and create an additional carbon sink of 2.5 to 3 billion tonnes of CO2 equivalent through additional forest and tree cover by 2030. According to data from the ministry of new and renewable energy, India’s total power capacity as of June 30 was 484.8 GW, with 242.04 GW (49.92%) from thermal/coal, 8.78 GW (1.81%) from nuclear, and 234.00 GW (48.27%) from renewable sources, including large hydro. The cabinet also said that India is on track to fulfil its commitments under the 2021 United Nations Climate Change Conference (COP26), held in Glasgow. Addressing a gathering that included over 120 heads of state at COP26, Prime Minister Narendra Modi had said India would increase its non-fossil fuel energy capacity to 500 GW by 2030, fulfil 50% of its energy requirements from renewable sources by 2030, reduce its total projected carbon emissions by 1 billion tonnes between now and 2030, reduce the carbon intensity of its economy by 45% by 2030, and achieve net-zero emissions by 2070. “As a commitment made to the Paris Agreement, the achievement of India’s NDC target is commendable and signals its intent to diversify its energy mix whilst continuing to tackle growing power demand. Having achieved this, all efforts must now be directed to raise the actual share of generation from renewables (combined with storage) in the power mix—which currently stands at 13% for solar and wind—to displace coal,” programme manager for climate change at the Centre for Science and Environment, Avantika Goswami, said. The cabinet committee on economic affairs, chaired by PM Modi, has granted enhanced delegation of powers to the National Thermal Power Corporation (NTPC) Limited, beyond the existing guidelines for Maharatna central public sector enterprises (CPSEs). This will allow NTPC to invest in its subsidiary, NTPC Green Energy Limited (NGEL), and enable NGEL to further invest in NTPC Renewable Energy Limited (NREL) and its other joint ventures and subsidiaries. The investment limit was raised from the earlier approved ₹7,500 crore to up to ₹20,000 crore for renewable energy capacity addition, in line with the goal of achieving 60 GW of renewable energy capacity by 2032.

Hyderabad’s Bolarum saw highest ozone pollution this summer, says study

Ozone pollution spiked in several parts of Hyderabad this summer, but it was the industrial belt of Bolarum that saw the worst of it. Between March 1 and May 31, Bolarum recorded 17 days when ground-level ozone levels breached the safe limit — the highest in the city — according to a research paper published by the Centre for Science and Environment titled ‘An invisible threat: Ground-level ozone – Metro cities’ based on a study by Anumita Roychowdhury and Sharanjeet Kaur. The study tracked air quality in five major cities — Hyderabad, Mumbai, Kolkata-Howrah, Bengaluru and Chennai — using data from 80 stations under the Continuous Ambient Air Quality Monitoring System (CAAQMS). As per the study, Bolarum is most chronically affected by ground-level ozone pollution, and exceeded the standard for 17 days in the study period. While the standard is 100 μg/m³ (micrograms per cubic metre of air), the levels of ozone nearly touched 140 μg/m³ on the days mentioned. There were no exceedances at other stations in the city barring ICRISAT which exceeded the standard for two days and Ramachandrapuram which exceeded for one day, totalling to 20 days of ozone exceedance in the city. The days of exceedance in Hyderabad were more concentrated between May 2 and 20. Good news is that the figure is 55% lower than what was recorded last summer. A comparison of May 2025 with May 2024 reveals that ground-level ozone is now lingering in the atmosphere even after sunset, and the average hourly ozone peak is 3% higher than last year, the study noted. At 45, Bengaluru recorded the highest number of days with ozone exceedance. Mumbai recorded 32 days, Kolkata 22 days, and Chennai recorded the lowest at 15 days. Unlike primary pollutants which are emitted directly from sources such as vehicles and industries, ground level ozone is formed through intricate chemical reactions involving nitrogen oxides, volatile organic compounds (VOCs) and carbon monoxide, which are the pollutants released by vehicles, power plants, factories and other combustion sources, the study said. In the presence of sunlight, these substances undergo a series of cyclic reactions that result in the ozone formation near the ground. VOCs also have natural sources such as vegetation adding to the complexity, which explains the higher levels at ICRISAT. What’s more threatening is that the ground level ozone can travel long distances, turning into a regional pollutant. It impacts agricultural productivity, threatening food security. Ozone is a highly reactive gas which can be harmful even with short duration exposure, and result in serious public health crisis, the study warned. Ground level ozone can inflame and damage the airways, increase susceptibility to infections and worsen respiratory conditions such as asthma, chronic bronchitis and emphysema. Children with underdeveloped lungs, order adults and people with existing respiratory conditions are particularly vulnerable. Hyderabad is prone to experience ozone exceedances during winter too, driven by cold, stagnant conditions and poor vertical mixing. But this winter, there was substantial improvement, with the city recording just nine days of exceedance which is a sharp decline from 43 days recorded during the winter of 2024, the study observed.

भारत के इन बड़े शहरों में ओजोन प्रदूषण बना मुसीबत, CSE की नई रिपोर्ट में आया सामने

इस गर्मी के मौसम में कोलकाता, बेंगलुरु, मुंबई, हैदराबाद और चेन्नई सहित भारत के सभी महानगरों में सतह के नजदीक ओजोन प्रदूषण की उच्च सांद्रता देखी गई। यह दावा थिंक टैंक सेंटर फॉर साइंस एंड एनवायरनमेंट (सीएसई) ने अपने नए विश्लेषण के आधार पर किया है। सीएसई के पूर्व के विश्लेषण से पता चला था कि इस गर्मी में कई दिनों तक दिल्ली के दैनिक वायु गुणवत्ता सूचकांक (एक्यूआई) में ठोस कणों के बजाय ओजोन मुख्य प्रदूषक था। सीएसई की शहरी प्रयोगशाला द्वारा किए गए नए विश्लेषण में खुलासा हुआ है कि प्राथमिक प्रदूषकों के विपरीत ओजोन किसी भी स्रोत से सीधे उत्सर्जित नहीं होता है। यह नाइट्रोजन ऑक्साइड (एनओएक्स), वाष्पशील कार्बनिक यौगिक (वीओसी) और कार्बन मोनोऑक्साइड (सीओ), वाहनों, बिजली संयंत्रों, उद्योगों और दहन के अन्य स्रोतों द्वारा उत्सर्जित प्रदूषकों से जुड़ी जटिल रासायनिक प्रतिक्रियाओं के माध्यम से बनता है। ये पदार्थ सूर्य के प्रकाश की उपस्थिति में प्रतिक्रिया करते हैं, जिससे सतह के नजदीक ओजोन का निर्माण होता है। सीएसई की कार्यकारी निदेशक अनुमिता रॉयचौधरी ने कहा, ‘यदि इस पर नियंत्रण नहीं किया गया तो यह एक गंभीर जन स्वास्थ्य संकट बन सकता है, क्योंकि ओजोन एक अत्यधिक प्रतिक्रियाशील गैस है और कम समय तक भी संपर्क में आने पर हानिकारक हो सकती है।’ उन्होंने कहा कि जहां उत्तर भारत के शहरों में गर्मियों में तीव्र गर्मी और तेज धूप के कारण ओजोन का स्तर अधिक रहता है, वहीं गर्म जलवायु वाले शहरों में भी अन्य मौसमों में ओजोन का स्तर लगातार बढ़ रहा है। रॉयचौधरी ने कहा कि वर्तमान नीति का विस्तार किया जाना चाहिए जिसमें बेहतर निगरानी, इस जहरीली गैस का शमन और उच्च स्थानीय जोखिम में कमी को शामिल करना शामिल हो। रॉयचौधरी ने कहा कि सतह के नजदीक ओजोन के स्तर को कम करने के लिए वाहनों, उद्योगों और सभी दहन स्रोतों से निकलने वाली गैसों पर कठोर नियंत्रण की आवश्यकता है। विश्लेषण के मुताबिक इस साल एक मार्च से 31 मई के बीच, मुंबई के निगरानी केंद्रों में 92 में से 32 दिनों में ओजोन का स्तर ज्यादा दर्ज किया गया, जो पिछले साल की इसी अवधि की तुलना में 42 प्रतिशत कम है। प्रसार के लिहाज से सबसे खराब दिन 29 मार्च था, जब 31 में से आठ केंद्रों से ओजोन के स्तर के ज्यादा होने की सूचना मिली। स्तह के नजदीक ओजोन की अधिकतम सांद्रता 90 माइक्रोग्राम प्रति घन मीटर दर्ज की गई। कोलकाता में, 92 में से 22 दिनों में ओजोन का स्तर सुरक्षित सीमा को पार कर गया। बेंगलुरु में 92 दिनों में से 45 दिनों में ओजोन का स्तर मानक से ज्यादा दर्ज किया गया जो पिछले साल की तुलना में 29 प्रतिशत अधिक है। सबसे बुरा दिन 31 मार्च का था, जब 14 में से चार केंद्रों पर ओज़ोन का स्तर मानक से ज़्यादा दर्ज किया गया। हैदराबाद में 20 दिन ऐसे रहे जब सतही ओजोन का स्तर अधिक था। शहर में ओज़ोन का उच्चतम स्तर 51 माइक्रोग्राम प्रति घन मीटर दर्ज किया गया। इसी प्रकार इस साल गर्मी में चेन्नई में 15 दिन ऐसे थे जब ओजोन प्रमुख प्रदूषक था जबकि पिछले साल एक दिन भी इस श्रेणी में दर्ज नहीं किया गया था।

Indian mega cities face high ozone pollution this summer: CSE

Every leading metropolis and mega city in India – including Kolkata, Bengaluru, Mumbai, Hyderabad and Chennai – has been struck by high ozone levels in the summer of 2025. Ground-level ozone pollution has spiked and concentrations have exceeded the eight-hour standards on a number of days. This has emerged from an analysis done by Centre for Science and Environment. The analysis has been done by the Urban Lab in CSE under its ‘air quality tracker’ initiative. The assessment highlights that unlike primary pollutants, ozone is not emitted directly from any source. It forms through intricate chemical reactions involving nitrogen oxides (NOx), volatile organic compounds (VOCs), and carbon monoxide (CO) — pollutants that are released by vehicles, power plants, factories and other combustion sources. In the presence of sunlight, these substances undergo a series of cyclic reactions that result in the formation of ozone at ground level. VOCs also have natural sources such as vegetation, adding to the complexity. Ground-level ozone accumulates not only in urban environments but can also travel long distances, turning into a regional pollutant. It can impact agricultural productivity and threaten food security. Given ozone’s highly reactive nature, the ambient air quality standards for it are set for eight-hour averages, instead of 24-hour averages. Anumita Roychowdhury, executive director, CSE, says: “If unchecked, this can become a serious public health crisis as ozone is a highly reactive gas and can be harmful even with short-duration exposures. In contrast to cities in north India where high summer temperatures and intense solar radiation can lead to ozone levels exceeding the standards, other cities in warm climates are experiencing consistent ozone exceedance during other seasons as well.” Roychowdhury adds: “The current policy focus must be expanded to include improved monitoring and mitigation of this toxic gas and reduction in high local exposures. Ozone mitigation needs drastic control over a range of gases from vehicles, industry and all combustion sources.” “Inadequate monitoring, limited data and inadequate methods of trend analysis have weakened the understanding of this growing public health hazard across cities of India. Instead of merely averaging out the levels for the city – which is the standard practice to estimate AQI — it is also important to capture adequately the high levels of local build-up and exposures in the hotspots and to design mitigation strategies accordingly ,” says Sharanjeet Kaur, deputy programme manager at the Urban Lab in CSE. The CSE review shows that exposure to ground-level ozone can inflame and damage the airways, increase susceptibility to infections, and worsen respiratory conditions such as asthma, chronic bronchitis and emphysema. Children with underdeveloped lungs, older adults, and individuals with existing respiratory conditions are particularly vulnerable. Ozone exposure increases the frequency and severity of asthma attacks, often leading to higher rates of hospitalisation. The investigation method: This assessment has traced trends during summer (March-May) between 2022 and 2025 (up to May 31). It is based on publicly available granular real time data (15-minute averages) from the Central Pollution Control Board’s official online portal – the Central Control Room for Air Quality Management. The data has been captured from 80 official stations under the Continuous Ambient Air Quality Monitoring System (CAAQMS), spread across Mumbai (31), Kolkata-Howrah (12), Bengaluru (14), Hyderabad (14) and Chennai (nine). Says Kaur: “Given the volatile and highly localised nature of ground-level ozone pollution build-up and its variability across space, and consistent with the global good practice, this analysis has considered station-level trends in terms of number of days exceeding the eight-hour standard over time.” She points out that as ozone formation depends on complex atmospheric chemistry and on photochemical reactions, its level varies across the time and space horizon. Meteorological parameters such as sunny and warm weather, stagnant wind patterns etc have a bearing on its formation. Kaur says: “This analysis tracks exceedances at each station in metro cities — breach of the standard by even one station is considered exceedance by the metro city in which the station is located. Days with multiple stations exceeding the standard indicates the severity of the spatial spread and number of people exposed.” The study has considered global good practice and taken on board the USEPA approach of computing eight-hour averages for a day and then checking for the maximum value among them to capture the daily ozone pollution level. USEPA assesses city-wide or regional AQI based on the highest value recorded among all stations of the city or the region. Thus, trends have been calculated in terms of number of days when the daily level has exceeded the eight-hour standard (referred as exceedance days hereafter). City-wise highlights Mumbai Summer trends: Between March 1 and May 31 this summer, Mumbai recorded ozone exceedance on 32 out of 92 days across its air quality monitoring stations. This marks a 42 per cent decline compared to the same period last year. The worst day in terms of spatial spread was March 29, when eight out of 31 monitoring stations reported exceedance. The highest regional ground-level ozone concentration reached was 90 µg/m³. Ozone hotspots: Chakala is the most chronically affected area in Mumbai. It exceeded the standard for 29 days between March and May. It is followed by Byculla and Kherwadi. Locational variations and relationship with other pollutants: The spatial distribution of ground-level ozone generally shows an inverse relationship with nitrogen dioxide. In areas with high NO ₂ concentrations, particularly near traffic-dense corridors, ozone formation is typically suppressed as ozone reacts with nitric oxide (NO) and breaks down to dissipate. Chakala consistently reports higher concentrations of both NO ₂ and ozone. Such localised variations underscore the complex interplay between precursor pollutants, meteorological conditions and emission sources that shape ozone behavior across different parts of the city. A comparison of May 2025 with May 2024 reveals that ground-level ozone is now persisting longer into the evening, even after sunset. However, the average hourly ozone peak this summer is 35 per cent lower than last year, indicating possible changes in atmospheric chemistry or precursor emissions. Daily trends show that when NO ₂ levels increase during morning and evening hours, it helps neutralise the ozone concentration and dissipate it. But ozone levels rise during off-peak hours when NO 2 levels are comparatively lower. Ozone build-up during other seasons: Unlike most northern cities, Mumbai records higher ground-level ozone concentrations during winter months during December – February. During the winter of 2024-25, the city experienced 87 days of ozone exceedance—a 10 per cent rise from the previous winter’s exceedance of 78 days. The atmospheric conditions, photochemical reactions and emissions levels would have contributed to this trend. Kolkata Summer trends: About 22 out of 92 days this summer (between 1 March and 31 May) have registered exceedance of ozone standards, as per the air quality monitoring stations of Kolkata. This marks a 45 per cent decline compared to previous summer. Kolkata has seen an overall improvement, with the average hourly ozone peak declining by 22 per cent this summer. Ozone hotspots: Rabindra Sarobar and Jadavpur have seen more days exceeding the standards compared to other locations. Locational variations and relationship with other pollutants: The spatial distribution of ground-level ozone generally shows an inverse relationship with nitrogen dioxide . In areas with high NO ₂ concentrations particularly near traffic-dense corridors, ozone formation is typically suppressed where ozone reacts with nitric oxide to break down and dissipate. It usually drifts and builds up in areas with less pollution. Ozone build-up during other seasons: While ozone pollution is typically associated with the summer months with strong sun in northern India, Kolkata has consistently recorded elevated ground-level ozone concentrations during the winter (November to February) and pre-monsoon seasons as well. The atmospheric conditions, relatively warmer climate, photochemical reactions and emissions levels would have contributed to this trend. During the winter of 2024-25, Kolkata experienced 28 days of ozone exceedance, marking a 7 per cent decline from the 30 days recorded in the previous winter. In the twin city of Howrah, 58 out of 92 days this summer (between 1 March and 31 May) have registered exceedance among its air quality monitoring stations. Dasnagar in Howrah has shown the maximum exceedance. During winter, Howrah has witnessed 81 days of ozone exceedance – increasing from 14 days the previous year. Bengaluru: Summer trends: Forty-five out of 92 days this summer (between 1 March and 31 May) have registered exceedance of ozone standards as per the data available from the air quality monitoring stations of Bengaluru. This marks a 29 per cent increase compared to last summer. The worst day in terms of spatial spread was March 31, when four out of 14 monitoring stations reported exceedance. Ozone hotspots: Hombegowda Nagar has seen the maximum exceedance. It exceeded the standard for 31 days this March-May. It is followed by Bapuji Nagar . Locational variations and relationship with other pollutants: A comparison of May 2025 with May 2024 shows a 28 per cent decline in average hourly ozone peaks — ozone is no longer persisting in the atmosphere after sunset, as was observed last year. Daily trends show that when NO ₂ levels increase during morning and evening hours, it helps neutralise the ozone concentration and dissipate it. But ozone levels rise during off-peak hours when NO 2 levels are comparatively lower. Ozone build-up during other seasons: In Bengaluru, ozone formation occurs in both winter and summer. However, this year’s data reveals a significant shift of ozone concentrations to the spring season (February to April): a 31 per cent increase is visible, compared to the same period last year. This points to a growing trend of early-season ozone formation, driven by warmer temperatures, intensified solar radiation, and possibly changing precursor emission patterns. Hyderabad Summer trends: There have been 20 days this summer (between 1 March and 31 May) that have registered exceedance among the air quality monitoring stations of Hyderabad. This marks a 55 per cent decline compared to last summer . The highest regional intensity was 51 µg/m³. Ozone hotspots: Bollaram is most chronically affected by ground-level ozone pollution. It exceeded the standard for 17 days this March-May. There have been no exceedances at other stations in the city barring ICRISAT (exceeding the standard for two days) and Ramachandrapuram (one day). Locational variations and relationship with other pollutants: A comparison of May 2025 with May 2024 reveals that ground-level ozone is now lingering in the atmosphere even after sunset, and the average hourly ozone peak is 3 per cent higher than last year. Ozone build-up during other seasons: Hyderabad frequently experiences wintertime ozone exceedances, driven by cold, stagnant conditions and poor vertical mixing. Urban traffic and industrial emissions, when combined with low dispersion, lead to ozone accumulation even under weaker winter sun. However, this winter season (December to January), the city witnessed a substantial improvement, recording just nine days of ozone exceedance, a sharp decline from 43 days during the previous winter. Chennai Summer trends: About 15 out of 92 days this summer (between 1 March and 31 May) have registered exceedance as per the data available from the air quality monitoring stations of Chennai. However, no exceedance was reported during the same period last year. In comparison, the summer of 2023 saw three exceedance days, while 2022 recorded 19. The highest regional intensity this summer was 64 µg/m³. Ozone hotspots: Alandur is most chronically affected by ground-level ozone pollution. It exceeded the standard for 15 days this March-May. There have been no exceedances at other stations in the city. Locational variations and relationship with other pollutants: Data from May 2025 reveals that ground-level ozone is now lingering in the atmosphere well after sunset, and the average hourly ozone peak has surged by 76 per cent compared to May 2024. Ozone build-up during other seasons : Chennai typically experiences rising ozone levels in the early summer months, when drier air, clear skies and reduced wind speeds delay pollutant dispersion. This allows for increased photochemical activity, especially during bright, sunny days with minimal atmospheric mixing. This summer (March to May 2025), Chennai recorded 15 days of ozone exceedance, marking a significant shift from zero exceedance days during the same period last year. Additionally, during the winter months (December–February), the number of ozone exceedance days has also risen from seven days last year to 10 days this winter. The way forward: Ground-level ozone is beginning to emerge as a pollutant of concern with cities experiencing days exceeding the eight-hour standards. While the level of exceedance is expected to be higher during the summer months with strong sun-shine days and heat, this is emerging as a round the year problem in the warmer climate. Says Roychowdhury: “Clean air action plan for cities and the states need to address this multi-pollutant challenge urgently. It is important to learn from the advanced economies that after controlling particulate pollution have fallen into the grip of rising NOx and ozone crisis. It is important to prevent this trap.” Clean air action plan for the city needs to integrate ozone mitigation to implement stringent measures to upscale zero emissions vehicles, clean industrial processes and fuels, eliminate waste burning with hundred percent remediation of legacy waste, collection, segregation and material recovery, and replace solid fuels with clean fuels in households. Integrate ozone in the Graded Response Action Plan to take emergency action to target the emitter of precursor gases like vehicles and industry that form ozone and to reduce short term exposures. Develop regional action plan on ozone : Ground-level ozone gets created in polluted areas but drifts and accumulates in cleaner urban environments, urban peripheries and surrounding rural areas affecting agricultural productivity and food security. While in polluted areas ozone further reacts with pollutants to dissipate, in cleaner environment it lives longer. Ozone is thus a regional pollutant that requires effective control at both local and regional level.

Ozone Pollution: भारत के इन शहरों के लिए खतरा बन रहा 'ओजोन' प्रदूषण, जानिए आखिर ये क्या होता है

वर्तमान समय में भारत के बड़े शहर प्रदूषण की मार झेल रहे हैं। अब इस बीच एक रिपोर्ट सामने आई है, जो हैरान करने वाली है। एक नई रिपोर्ट में जानकारी सामने आई है कि भारत के बड़े शहरों जैसे कोलकाता, बेंगलुरु, मुंबई, हैदराबाद और चेन्नई में इस साल गर्मी के दौरान जमीन के स्तर पर ओजोन प्रदूषण काफी बढ़ा हुआ था। सेंटर फॉर साइंस एंड एनवायरनमेंट (CSE) की नई रिपोर्ट में कहा गया है कि शहरों में ओजोन का स्तर कई दिनों तक आठ घंटे के मानक से अधिक रहा। यह प्रदूषण बेहद खतरनाक है, जिसका असर लोगों के स्वास्थ्य और खेती पर बुरा असर पड़ रहा है। आइए जानते हैं कि आखिर समस्या क्या है? क्या होता है ओजोन प्रदूषण? तीन ऑक्सीजन अणुओं से बनने वाली ओजोन एक गैस है। ऊंचे आसमान में यहसूरज की हानिकारक किरणों से बचाती है, लेकिन जमीन के पास यह प्रदूषण बन जाता है। किसी स्रोत से यह सीधे नहीं निकलता है, बल्कि वाहनों, उद्योगों और बिजलीघरों से निकलने वाली नाइट्रोजन ऑक्साइड (NOx), वाष्पशील कार्बनिक यौगिक (VOCs) और कार्बन मोनोऑक्साइड (CO) के सूरज की रोशनी में रासायनिक प्रतिक्रिया से बनता है। यह बहुत प्रतिक्रियाशील गैस होती है, जो हवा में लंबी दूरी तक फैल सकती है। इससे यह शहरों से लेकर गांवों तक को प्रभावित करती है। कई शहरों में ओजोन का स्तर खतरनाक स्तर पर पहुंच गया रिपोर्ट के मुताबिक, इस साल मार्च-मई में कई शहरों में ओजोन का स्तर बेहद खतरनाक हो गया था। दिल्ली की रिपोर्ट पहले ही जारी की जा चुकी है। इसकी वजह से इस अध्ययन में उसे शामिल नहीं किया गया। बेंगलुरु में गर्मी के दौरान 92 दिनों में से 45 दिन ओजोन का स्तर मानक से अधिक रहा। यह बीते साल की तुलना में 29 फीसदी बढ़ा है। होमबेगोड़ा नगर सबसे ज्यादा प्रभावित क्षेत्र रहा। मुंबई की बात करें, तो 32 दिन ओजोन स्तर बढ़ा, जो साल 2024 की तुलना में 42 फीसदी कम है। चकाला सबसे प्रभावित इलाका रहा। कोलकातामें 22 दिन ओजोन स्तर बढ़ा। यहां भी बीते साल की तुलना में 45 प्रतिशत कम है। रवींद्र सरोवर और जादवपुर हॉटस्पॉट थे। हैदराबाद में 20 दिन ओजोन स्तर बढ़ा। यह बीते साल की तुलना में 55 फीसदी कम है। बोल्लारम सबसे ज्यादा प्रभावित रहा, जबकि चेन्नई में 15 दिन ओजोन स्तर बढ़ा, जो बीते साल शून्य था। यहां आलंदुर सबसे प्रभावित क्षेत्र र। इन शहरों में ओजोन का स्तर सर्दियों और अन्य मौसमों में भी बढ़ रहा है, खासकर गर्म जलवायु वाले इलाकों में। हर शहर में कुछ खास इलाकों में ओजोन का स्तर सबसे अधिक बढ़ता है। यहां पर प्रदूषण का असर और गंभीर होता है। ओजोन से सांस की नली को नुकसान पहुंचता है। अस्थमा और दमा जैसी बीमारियों को बढ़ाता है। इससे फसलों को भी नुकसान पहुंचता है।

Mega cities in India see high concentration of ozone pollution this summer

All mega cities in India, including Kolkata, Bengaluru, Mumbai, Hyderabad and Chennai, saw high concentration of ground-level ozone pollution this summer season, according to a new analysis by think tank Centre for Science and Environment (CSE). A previous analysis had shown that ozone, instead of particulate matter, was the main pollutant in Delhi's daily Air Quality Index (AQI) on several days this summer. The new analysis by the CSE's Urban Lab highlighted that ozone, unlike primary pollutants, is not released directly from any source. It forms through complex chemical reactions involving nitrogen oxides (NOx), volatile organic compounds (VOCs) and carbon monoxide (CO), pollutants emitted by vehicles, power plants, industries and other sources of combustion. These substances react in the presence of sunlight, leading to the formation of ozone at the ground level. Anumita Roychowdhury, executive director at the CSE, said: "If unchecked, this can become a serious public health crisis as ozone is a highly-reactive gas and can be harmful even with short-duration exposures." She added that while cities in north India experience high ozone levels in summer due to intense heat and strong sunlight, cities in warmer climates are also seeing consistent ozone exceedance in other seasons. The current policy focus must be expanded to include improved monitoring, the mitigation of this toxic gas and a reduction in high local exposures. Ozone mitigation needs drastic control over a range of gases from vehicles, industry and all combustion sources, Roychowdhury said. Sharanjeet Kaur, deputy programme manager at the CSE's Urban Lab, said: "Inadequate monitoring, limited data and inadequate methods of trend analysis have weakened the understanding of this growing public health hazard across cities of India. Instead of merely averaging out the levels for the city, which is the standard practice to estimate the AQI, it is also important to adequately capture the high levels of local build-up and exposures in the hotspots and design mitigation strategies accordingly." Between March 1 and May 31 this year, Mumbai recorded ozone exceedance on 32 out of 92 days across its monitoring stations, a 42-per cent drop compared to the same period last year. The worst day in terms of spread was March 29, when eight out of 31 stations reported exceedance. The highest ground-level ozone concentration recorded was 90 micrograms per cubic metre. In Kolkata, ozone levels crossed the safe limit on 22 out of 92 days, a 45-per cent decline compared to last summer. The city also saw an overall improvement, with the average hourly ozone peak dropping by 22 per cent. Bengaluru saw ozone exceedance on 45 of the 92 days, a 29-per cent increase from last year. The worst day was March 31, when four of 14 stations recorded levels above the standard. Hyderabad recorded 20 ozone exceedance days, a 55-per cent drop compared to last summer. The highest ozone level recorded in the city was 51 micrograms per cubic metre. Chennai saw ozone exceedance on 15 days this summer. No such exceedance was reported during the same period last year. In comparison, the city had three exceedance days in 2023 and 19 in 2022. The highest level this year was 64 micrograms per cubic metre.

India Reverses Key Policy, Exempting Most Coal-fired Power Plants from Emission Rules

On 11 July, the Indian government changed its own rules, exempting most coal-fired power plants from installing technology to reduce sulphur dioxide (SO2) emissions. This reverses a key environmental policy launched in 2015 to cut SO2 emissions. It means that about 78% of India’s 537 or so thermal power plant units do not have to install machinery to reduce SO2 emissions called Flue Gas Desulfurization systems (FDGs). India is the largest SO2 emitter, mostly from such plants. The gas is an air pollutant linked to respiratory disorders and other health impacts, as well as ecological impacts such as acid rain. While the move has been questioned by experts, the government has hit back by denying that it is reversing the policy. In an X post, India’s environment ministry described criticism of the change as a “gross misinterpretation”, adding: “The revised sulphur dioxide emission policy is not a rollback” and that it remains “fully committed” to science-based air quality management: The report regarding the recent notification issued by the Ministry regarding the applicability of Sulphur Dioxide norms in respect of Thermal power Plants has been grossly misinterpreted. The norms of Sulphur Dioxide emissions from Thermal Power Plants notified on 11th July… pic.twitter.com/0aKpNaEXgy — MoEF&CC (@moefcc) July 14, 2025 Referring to an unnamed media report, the ministry added that it is “not aligned with empirical evidence, exaggerates the health and air quality impacts of sulphur dioxide, and underestimates the trade-offs of large-scale FGD implementation.” However, the near-total reversal of the policy “weakens pollution control efforts and endangers public health,” according to the Centre for Science and Environment, an environmental think tank. The new policy divides the thermal power plants into three categories. Of the 537 units which were supposed to get FGDs, now only 65 units (12%) must have these in category A. In the case of a further 66 units, category B, officials will determine on a case-by-case basis whether they need to install FGDs . The remaining 406 units, category C, are now exempted. This categorisation can be problematic. Similar pollution sources now have “different” environmental standards within India, points out an editorial in The Hindu newspaper. When the emission cuts were ordered in 2015, there was no such differentiation. All coal-fired power plants had to implement it. Herein, researchers point out, lies another significant dilution. Of the 36 coal-fired power units around Delhi, many have been shut down in the past during peak pollution times. However, 22 of them are now exempt from installing FGDs.

Ozone pollution surges across major Indian cities this summer, posing serious health risk

All mega cities in India, including Kolkata, Bengaluru, Mumbai, Hyderabad and Chennai, saw high concentration of ground-level ozone pollution this summer season, according to a new analysis by think tank Centre for Science and Environment (CSE). A previous analysis had shown that ozone, instead of particulate matter, was the main pollutant in Delhi's daily Air Quality Index (AQI) on several days this summer.All mega cities in India, including Kolkata, Bengaluru, Mumbai, Hyderabad and Chennai, saw high concentration of ground-level ozone pollution this summer season, according to a new analysis by think tank Centre for Science and Environment (CSE). A previous analysis had shown that ozone, instead of particulate matter, was the main pollutant in Delhi's daily Air Quality Index (AQI) on several days this summer. The new analysis by the CSE's Urban Lab highlighted that ozone, unlike primary pollutants, is not released directly from any source. It forms through complex chemical reactions involving nitrogen oxides (NOx), volatile organic compounds (VOCs) and carbon monoxide (CO), pollutants emitted by vehicles, power plants, industries and other sources of combustion. These substances react in the presence of sunlight, leading to the formation of ozone at the ground level. Anumita Roychowdhury, executive director at the CSE, said: "If unchecked, this can become a serious public health crisis as ozone is a highly-reactive gas and can be harmful even with short-duration exposures." She added that while cities in north India experience high ozone levels in summer due to intense heat and strong sunlight, cities in warmer climates are also seeing consistent ozone exceedance in other seasons. The current policy focus must be expanded to include improved monitoring, the mitigation of this toxic gas and a reduction in high local exposures. Ozone mitigation needs drastic control over a range of gases from vehicles, industry and all combustion sources, Roychowdhury said. Sharanjeet Kaur, deputy programme manager at the CSE's Urban Lab, said: "Inadequate monitoring, limited data and inadequate methods of trend analysis have weakened the understanding of this growing public health hazard across cities of India. Instead of merely averaging out the levels for the city, which is the standard practice to estimate the AQI, it is also important to adequately capture the high levels of local build-up and exposures in the hotspots and design mitigation strategies accordingly." Between March 1 and May 31 this year, Mumbai recorded ozone exceedance on 32 out of 92 days across its monitoring stations, a 42-per cent drop compared to the same period last year. The worst day in terms of spread was March 29, when eight out of 31 stations reported exceedance. The highest ground-level ozone concentration recorded was 90 micrograms per cubic metre. In Kolkata, ozone levels crossed the safe limit on 22 out of 92 days, a 45-per cent decline compared to last summer. The city also saw an overall improvement, with the average hourly ozone peak dropping by 22 per cent. Bengaluru saw ozone exceedance on 45 of the 92 days, a 29-per cent increase from last year. The worst day was March 31, when four of 14 stations recorded levels above the standard. Hyderabad recorded 20 ozone exceedance days, a 55-per cent drop compared to last summer. The highest ozone level recorded in the city was 51 micrograms per cubic metre. Chennai saw ozone exceedance on 15 days this summer. No such exceedance was reported during the same period last year. In comparison, the city had three exceedance days in 2023 and 19 in 2022. The highest level this year was 64 micrograms per cubic metre. PTI GVS RC

How these women are putting forgotten foods back on our plates

Bichu booti, Sana Hua Nimbu, Seema Chintha Daal, Meetha Karela are some of the many regional wild foods and microgreens that evoke childhood memories of love, sharing and the joy of eating together. But as green spaces shrink in cities, food has been reduced to what’s available in the market. Wild edibles, traditional berries and forest fruits have largely vanished from urban Indian plates. “Biodiversity was once an integral part of everyday Indian meals, but it’s gradually disappearing,” says Vibha Varshney, head of biodiversity and food at the New Delhi-based think-tank Centre for Science and Environment (CSE). However, a clutch of Indian women are working to bring these forgotten foods back into our daily diets. They were part of the launch of ‘My Food Story’, a digital platform by CSE that celebrates traditional knowledge, forgotten ingredients, recipes and the powerful stories they carry. Uttarakhand-based food writer Megha Prakash shares how you can’t actively look for these ingredients—you just chance upon them while visiting a house or a market or in conversations with locals. She recalls a vegetable called Meetha Karela found in the hills, which isn’t a bitter gourd but tastes like cucumber. Or an Indian pokeweed, which is poisonous unless cooked from its tender young leaves. Goa-based Anumitra Ghosh Dastidar, chef and restaurateur behind Edible Archives, Bento Bento, and Yo Colombo, talks about how she changes her menu with the seasons, introducing traditional produce that often isn’t cultivated but foraged. “There’s a need to build a network of people who can collect these ingredients regularly,” she says. Ghosh Dastidar has built a team of 5-6 local women who are the backbone of her initiative. She uses ingredients like amade—a sweet-sour fruit commonly found in Goa—and even taro leaves and stems in her recipes. “It’s important to have these on restaurant menus because that’s what inspires people to try them at home,” she says, emphasising the role chefs can play in bringing back indigenous ingredients. Devi Lakshmikutty, co-founder of BioBasics, an online organic brand from Coimbatore, speaks about the critical role social media has played in creating curiosity and awareness about these foods. But she cautions that it shouldn’t be a one-time experiment. “People must cook these foods regularly,” she says. “There has to be a consistent effort to include them in daily diets—only then will farmers continue to grow them.” As Lakshmikutty puts it, “It’s good for us, good for the farmers, and good for the environment.” For nutrition and culinary consultant Sangeeta Khanna, the joy lies in finding and cooking wild foods. She warns that as urban consumers get more used to artificial flavours, it becomes harder to enjoy simpler recipes. “Our palate is no longer used to food in its elemental form,” she says. Khanna’s solution: start by incorporating these ingredients into familiar recipes to make them more acceptable. She highlights that these wild leaves, flowers and berries carry distinct nutritional profiles—packed with micronutrients and macronutrients that cultivated foods often lack. These help enrich gut microbiome and promote gut biodiversity within our bodies. However, Khanna also warns against harvesting from polluted lands or water sources, especially those contaminated with heavy metals.

Indian mega cities face high ozone pollution this summer: CSE

Major Indian cities are grappling with high levels of ground‑level ozone this summer, according to the Centre for Science and Environment (CSE). Bengaluru, Mumbai, Kolkata, Hyderabad, and Chennai recorded multiple days where ozone levels crossed the safe limit. Bengaluru led the rise. The city saw a 29 percent jump in days exceeding the ozone standard compared to last year. “The trend is worrying,” said Anumita Roychowdhury, Executive Director at CSE. “Ozone is a toxic gas and even short‑term exposure can trigger serious respiratory issues.” Ozone is not directly emitted. It forms through chemical reactions involving nitrogen oxides, volatile organic compounds, and carbon monoxide. Sunlight drives this reaction, making summer particularly vulnerable. Unlike pollutants such as PM2.5 or nitrogen dioxide, ozone forms through reactions in the atmosphere. Vehicles, power plants, factories, and other combustion sources emit the gases that trigger ozone. VOCs, one of the key components, also come from natural sources like plants. Once formed, ozone can travel far, affecting both cities and rural areas. “Ground-level ozone can hurt crop yields and threaten food security,” Roychowdhury said. CSE’s analysis used real‑time data from 80 monitoring stations across the five cities. Each station’s data was evaluated for the number of days when eight‑hour average ozone levels breached national standards. The data came from the Central Pollution Control Board’s public platform. The study covered March to May from 2022 to 2025. It used the US Environmental Protection Agency’s method—measuring the highest eight-hour average each day from each station. If even one station exceeded the limit, it counted as a breach for the city. “Ozone build‑up is highly localised and influenced by temperature, wind, and precursor gases,” explained Sharanjeet Kaur, Deputy Programme Manager at CSE. “One or two stations exceeding the limit signals local hotspots that need immediate attention.” She added that average city-level data hides these spikes. “One part of a city might show high ozone while another doesn’t. Averaging hides the risk,” Kaur said. CSE warned that high ozone levels damage the lungs. It inflames airways, worsens asthma, and increases the risk of infections. Children, older adults, and people with existing respiratory conditions face the greatest risk. “Ozone attacks the lungs,” said Roychowdhury. “It increases asthma attacks and hospital visits.” Experts note that ozone and nitrogen dioxide interact in complex ways. Traffic-heavy areas with more NO₂ can suppress ozone, while cleaner zones allow it to build up and persist. “We can’t ignore ozone anymore,” said Roychowdhury. “It’s not just a summer problem. Warmer regions now face year‑round risk.” She added that developed countries saw a rise in ozone after reducing particulate matter without cutting nitrogen oxide emissions. India could face the same pattern. “This is a growing public health hazard,” said Kaur. “Without better monitoring and focused action, we risk long‑term damage to people and the environment.” CSE called for immediate action across all combustion sources—vehicles, industries, waste burning, and household fuels. It also urged the government to include ozone in clean air action plans and emergency systems. “Ozone pollution is not a future threat,” said Roychowdhury. “It’s already here.”

Explained: Centre's U-turn on installing anti-pollution systems in thermal power plants

The central government this week overturned a decade-old mandate to install flue gas desulphurisation (FGD) systems in thermal power plants. From now on, only about 11 percent of India’s 600 thermal power plant (TPP) units have to mandatorily install FGD systems, which are pollution control devices designed to remove sulphur dioxide (SO₂) from the flue gas produced during the combustion of coal in TPPs. The 11 percent of the plants are the ones located within a 10 km radius of the National Capital Region or are cities with a population of at least a million, as per the 2011 Census. For such plants, the government in its latest decision has extended the FGD installation deadline to December 30, 2027, from 2017. The latest decision is also expected to cut electricity costs by 25–30 paise per unit, according to a section of the industry, as 78 percent of the coal-fired power plants, including private ones, will not have to install the FGD systems, the cost of which ranges between Rs 50 lakh per megawatt, as per state-run NTPC, and Rs 1.2 crore per megawatt, as per private players. The relaxation in the norms comes at a time when India is rushing to add 90 gigawatts (GW) of coal-fired power generation capacity in the coming six years to meet the country's growing energy needs. India's peak power demand is projected to touch 458 GW by 2032, and to meet that, the country plans to increase its overall power generation capacity to 900 GW from the current 476 GW. Air pollution had become a severe public health crisis in India by 2015, with major cities like Delhi, Mumbai, Kolkata, and Bengaluru experiencing dangerously high levels of fine particulate matter (PM2.5) and other pollutants. This was largely due to emissions from vehicles, industrial processes, and power plants, particularly coal-fired TPPs. Besides, in 2015, India had just participated in the Paris Agreement under the UN Framework Convention on Climate Change (UNFCCC). As part of its climate action goals, India committed to reducing carbon intensity and increasing its reliance on renewable energy. To tackle air pollution and reduce carbon intensity, the Union environment ministry and the Central Pollution Control Board (CPCB) identified flue gas from thermal power plants as one of the target areas. Flue gas is the mixture of gases such as carbon dioxide, sulphur dioxide, nitrogen oxides, and carbon monoxide that is produced as a byproduct of combustion in power plants or any industrial process that burns fuel. Back then, the government, based on an IIT Kanpur report, stated that sulphur dioxide (SO₂), a byproduct of coal combustion in power plants, was a significant contributor to air pollution, leading to smog and health problems. Hence, the Union environment ministry decided to mandate all existing thermal power plants as well as upcoming ones to get FGD systems installed. The Ministry of Power, NTPC and independent power producers had all urged the environment ministry to impose the mandate in a phased manner by either asking the old plants due for repair and maintenance to be taken up first or ruling it for upcoming plants. However, the environment ministry, backed by orders from the Supreme Court, refused to budge. NTPC Ltd ended up being the only power producer which installed FGD systems in about 11 percent of its power plants, which cost it about $4 billion, or Rs 50 lakh, per megawatt. "SO₂ levels in the plants which do not have FGD range from 800-1200 micrograms per cubic metre, and units which have FGD, the levels are coming between 20-25 (µg/m³). But there's not much impact in PM2.5 and PM10. In fact, we have seen that the desulphurisation process also releases some PM2.5. We had opposed the move since the beginning, but NTPC was compelled to comply as we had to submit an affidavit in the Supreme Court," said a senior NTPC official requesting anonymity. Private players such as Adani Power, JSW Energy and Tata Power continued to wait and watch and did not install FGD systems, saying that implementing it would result in a rise in cost of electricity to the end consumer. Why is the govt exempting thermal power plants now? Justifying its reversal of the mandate, the environment ministry on July 14 said the decision was a “scientifically justified shift towards more targeted, cost-effective and climate-coherent regulation.” “Current exposure levels provide no credible evidence to suggest that SO₂, under prevailing ambient conditions, is a major public health concern. Moreover, sulfate aerosols formed from SO₂ constitute a relatively small fraction of PM2.5,” the Ministry of Environment and Climate Change said in a statement. A detailed analysis carried out by IIT Delhi shows that sulfate contributes only 0.96 percent to 5.21 percent of PM2.5 and 0.57 percent to 3.67 percent of PM10 in cities near TPPs, it added. The government said that the new notification is “based on extensive consultations with stakeholders and research institutions” regarding the effectiveness and rationale behind stack emission standards for SO₂ on 537 TPPs throughout the country, and its role in overall ambient air pollution of the region. This time the government mentioned that the latest decision was based on research studies by IIT Delhi, the National Institute of Advanced Studies, as well as by the National Environmental Engineering Research Institute (NEERI) — a constituent laboratory of the Council of Scientific and Industrial Research (CSIR), besides scientific examination by the Central Pollution Control Board. Dilution of anti-pollution measures? According to Shreya Verma, programme manager, Centre for Science and Environment (CSE), the new SO₂ norms fall short of India’s clean air commitment. "Nearly a decade after SO₂ limits were first notified in 2015, MoEF&CC’s revised rules also leave Category B plants to case-by-case discretion — effectively mandating SO₂ norms for only 11 percent of capacity (Category A). This weakens regulatory intent, delays pollution control, and poses a risk to public health. SO₂ is a major contributor to PM2.5 — we cannot afford diluted action. India needs strong, uniform standards to meet its clean air goals," she said. The notification states that Category B – located within a 10 km radius of critically polluted areas (CPA) or non-attainment cities (NAC) – may or may not have to install FGD. This would depend upon a decision by a committee of experts (Expert Appraisal Committee) – an existing body constituted by the environment ministry that grants environment clearances to proposed TPP projects.

SO2 emission not a ‘major public health concern’—environment ministry defends revised norms after flak

The Centre has defended its decision to push the sulphur emission norms compliance for thermal power plants to 2027, saying that it is based on “extensive consultations” and “scientific studies.” The notification, released Friday, postponed the compliance date for thermal power plants to install sulphur dioxide (SO2) emissions for the sixth time after the order was first passed in 2015. This time, the Union Ministry of Environment, Forest and Climate Change (MoEFCC) also exempted 78 percent of the 537 existing thermal power plants from having to install the SO2 emissions regulation machinery at all. Under the new regulations, only Category A power plants, which are 9 percent of total power plants—which are within 10 km of NCR or cities with million-plus populations—are mandated to install flue-gas desulphurisation systems (FGDs). For the Category B power plants, the FGD installations will be on a case-by-case basis, while Category C facilities, which make up 462 plants in total, have been fully exempted from installing these systems. Despite the measure first being introduced in 2015, only 39 power plants in India have installed the FGDs as of 1 August 2024. “Exempting a large number of thermal power plants—around 78 percent—and mandating emission controls on only 11 percent of India’s total thermal power capacity falls far short of supporting the country’s clean air goals,” said Shreya Verma, programme manager of industrial pollution programme at Centre for Science and Environment (CSE). According to an MoEFCC note released Monday, the decision to exempt certain power plants from installing FGDs was taken after examining sulphur emissions from TPPs, air quality data from near TPPs, and the cost of installing FGDs. It said the total cost of installing FGDs in all of India’s power plants would be Rs 2.4 lakh crore, which is an investment that should be carefully ‘scrutinised’. “Indian coal has very low sulphur content, and in many power plants the Ministry found that even without FGDs, the national ambient air quality standards were met,” explained Alok Kumar, former Union power secretary. “And given how FGDs increase electricity costs for consumers and also CO2 emissions, the government decided to only mandate it where necessary.” Sulphur dioxide is one of the byproducts of coal and lignite thermal power plants, and is a ‘criteria pollutant’ according to CSE. An IIT Delhi study from 2022 describes how sulphur dioxide can turn to sulphate particulate matter during and after emissions, a main component of PM2.5. SO2 has been variously ascribed to different health effects like respiratory problems and lung disorders since 2005, both by Indian and international sources. Most FGD systems use limestone or other alkaline products to remove sulphur dioxide from the gases released during the coal-firing process in power plants. However, the MoEFCC said it is necessary to examine the issue in an Indian context. “Current exposure levels provide no credible evidence to suggest that SO2, under prevailing ambient conditions, is a major public health concern,” read the Ministry’s post on X. The FGD compliance story, so far The MoEFCC first decided to implement sulphur dioxide regulation norms in 2015, and gave thermal power plants until 2017 to install FGD systems. Thermal power plants make up 46 percent of India’s total electricity capacity, and 70 percent of electricity generation. An independent analysis by the Centre for Research on Energy and Clean Air in 2024 revealed that India was the largest producer of SO2 from electricity generation. In 2022-23, the study showed that coal power plants produced 4327 kilotonnes of SO2, which was 240 times more than what was produced by burning 8.9 million tonnes of paddy. A CSE factsheet describes that the power ministry in 2015 put forth a new plan to extend the emissions compliance deadline to 2024, and was granted an extension until 2022. Since then, the deadline has been extended three more times, before the 11 July order, which extended it for the sixth time after “consultations with stakeholders and research institutes.” According to the MoEFCC’s note, 94 percent of the coal used in the power plants is domestic coal, which only has 0.5 percent sulphuric content, much lower than the coal used elsewhere. It also said that 490 out of 492 cities monitored in 2023 were within the prescribed SO2 levels in their ambient air quality levels. “Government sources have said that Indian coal has low sulphuric content, but they also say it has low calorific value, so more coal is needed to produce the same 1W of electricity. This increases SO2 production, too,” said Verma. “Also, SO2 is a problem because it gets converted to sulphate matter, which forms PM2.5. That happens over a long period and has transboundary impacts.” The Ministry’s note pointed to a 2024 IIT Delhi report, which says the contribution of sulphate to PM2.5 and PM10 is between 2 and 6 percent, and that FGD installations in power plants would only result in a “marginal improvement” of air quality. However, this study directly contradicts the 2022 study conducted by the same team, which had said installing FGDs would decrease surface sulphate aerosols even in areas 200 km away from the power plants. “It is very worrying that the number of people who may suffer or die is not being acknowledged or addressed in any of the reports. Scientific articles showed that coal-fired power plants led to 47,000 deaths in 2014, 62,000 deaths in 2017, and 78,000 deaths in 2018,” reads an article by the Centre for Research on Energy and Clean Air (CREA) in 2025. However, the Ministry said it is committed to a “comprehensive, science-based strategy” for air quality management, and that regulations for SO2 control should not be dictated by “rhetorical observations” but by real-time impacts on PM2.5.

Ministry supports revised SO2 emission norms, slams critics

The government on Monday defended its recent move to ease sulphur dioxide (SO₂) emission norms for thermal power plants, saying the decision was based on detailed scientific studies and stakeholder consultations, and that media reports terming the move a “regulatory dilution” have “grossly misinterpreted” the notification. The statement came days after the Union environment ministry on July 11 extended deadlines and exempted a large number of coal plants from installing flue gas desulphurisation units. “The media reports misrepresent both the scientific evidence and the environmental policy rationale underlying the revised notification,” the ministry said in its statement on Monday. It said the revised norms were framed after “extensive consultations with stakeholders and research institutions regarding the effectiveness and rationale behind stack emission standards for SO2 on 537 TPPs throughout the country, and its role in overall ambient air pollution of the region.” Further, the ministry said sulfate aerosols from SO2 constitute a relatively small fraction of PM 2.5, suggesting that was not a major public health issue, as suggested by environmental groups. “Current exposure levels provide no credible evidence to suggest that SO2, under prevailing ambient conditions, is a major public health concern. Moreover, sulphate aerosols formed from SO2 constitute a relatively small fraction of PM2.5,” it said. Addressing SO2 emissions is critical due to their contribution to secondary particulate pollution, experts have warned. Quoting a study by IIT Delhi, the ministry said, “A detailed analysis carried out by IIT Delhi shows that sulfate contributes only 0.96 per cent to 5.21 per cent of PM2.5 and 0.57 per cent to 3.67 per cent of PM10 in cities near TPPs (thermal power plants).”The ministry said the assertion that sulphur compounds contribute 12-30 per cent of PM2.5 is an unsubstantiated claim and not supported by any rigorous scientific studies conducted in major Indian cities and it significantly overstates the contribution of SO2 in India’s particulate pollution burden. On July 12, Centre for Science and Environment said: “The revised notification weakens India’s clean air ambitions by diluting or removing SO₂ norms for Category B and C thermal power plants, which together represent most of the country’s coal capacity. Together, these exemptions threaten to derail progress on industrial air pollution control, compromise public health, and reduce the effectiveness of India’s environmental regulations.”

India can't wish away coal - but can it be made cleaner?

"This means that there is no other option [other than thermal energy for constant supply] unless and until we have large-scale storage quantities in the system," said Rajiv Porwal, director with Grid India, the grid controller of India under the ministry of power, speaking at the 1July event, organised by the Centre for Science and Environment (CSE). India has always taken a hard position on coal, arguing that it is crucial for its energy security and developmental needs. But energy experts and environment campaigners are increasingly saying it should at least try to decarbonise or curtail emissions from coal-fired power plants, if it can't be phased out altogether. "You can't wish away coal," Ashok Lavasa, a former secretary of union ministries of finance, and environment, forest and climate change, said at an event on 1 July. "The question is, if coal is king, then can it be a benevolent king?" This signals to the fact that, realistically speaking, coal - albeit cleaner coal - may remain the primary power source of energy in India, despite years of international climate talks asking for the highly polluting fossil fuel to be phased out entirely. But why has India - the world's third largest carbon emitter - decided to stick to coal in the first place? After all, the country has international obligations to significantly cut its carbon emissions, along with its own target to bring down the levels to net zero by 2070. A part of the answer lies in the rising power demands of the country. India's electricity demand has grown by more than 9% between 2021 and 2025, surpassing a previous prediction of 6.6% - and it is now forecasted to double by 2030. Coal-fired power plants have generated more than 70% of the total electricity supply every year since the early 2000s - a figure that remains unchanged. But the environmental cost of this reliance on coal is huge. Estimates suggest that India's electricity generation alone accounts for more than 40% of the annual carbon emissions – and nearly three-quarters of that electricity comes from coal-burning. The country has made progress in meeting its renewable energy targets - it contributes 46% of India's total installed capacity - but renewable sources have limitations. They generate electricity when the sun is up and the wind is blowing. Even at daytime, experts say, supply from renewables can fluctuate, whereas thermal plants remain a constant source of electricity and are able to cater to peak demand in the evenings and at nighttime. What's more, India's energy storage capacity - or the ability to store excess electricity from renewables at daytime - has not been able to keep pace with the expansion of resources. "This means that there is no other option [other than thermal energy for constant supply] unless and until we have large-scale storage quantities in the system," said Rajiv Porwal, director with Grid India, the grid controller of India under the ministry of power, speaking at the 1July event, organised by the Centre for Science and Environment (CSE). Experts say constant supply from thermal plants is crucial for the stability of the grid, or the network of towers and transmission lines that carries electricity from power plants to consumers. "Any large mismatch of demand and supply will destabilise the grid and that can mean power-cuts and blackouts, similar to what we recently saw in Spain," says Anjan Kumar Sinha, an independent power sector expert. With all these factors at play, India is looking to reduce emissions from coal-fired power plants, instead of phasing out coal completely. A recent report by the CSE said that decarbonisation from coal-based thermal plants alone can cut down the country's greenhouse gas emissions by 30%. This is particularly significant given the country's commitment to reduce emissions intensity (carbon emissions produced per unit of a country's economic output) by 45% by 2030 under the United Nations Framework Convention on Climate Change.

India’s Struggle with Coal: The Challenges of Transitioning to Clean Energy

India’s reliance on coal for energy generation remains a contentious issue as the country grapples with rising electricity demands and international climate commitments. Despite being the world’s third-largest carbon emitter, India continues to prioritize coal, which accounts for over 70% of its electricity supply. Experts argue for a shift towards decarbonization of coal-fired power plants, highlighting the need for cleaner energy solutions while acknowledging the challenges posed by renewable energy sources. Coal’s Dominance in India’s Energy Landscape India’s energy strategy has long been anchored in coal, which is viewed as essential for meeting the country’s growing electricity demands. The nation has seen a significant increase in electricity consumption, with a growth rate exceeding 9% from 2021 to 2025, surpassing earlier projections. This surge in demand is expected to double by 2030, reinforcing coal’s role as the primary energy source. Since the early 2000s, coal-fired power plants have consistently generated more than 70% of India’s total electricity supply. However, this heavy reliance on coal comes at a steep environmental cost, contributing to over 40% of the country’s annual carbon emissions. While India has made strides in renewable energy, accounting for 46% of its total installed capacity, these sources face inherent limitations. Renewable energy generation is contingent on weather conditions, leading to fluctuations in supply. Consequently, coal remains a reliable option for meeting peak electricity demands, particularly during evenings when renewable sources may not suffice. Challenges in Transitioning to Cleaner Energy Despite the push for renewable energy, India’s energy storage capacity has not kept pace with the growth of renewable resources. Experts emphasize the need for large-scale energy storage solutions to ensure a stable electricity supply. Rajiv Porwal, director of Grid India, highlighted that without adequate storage, thermal energy remains the only viable option for consistent electricity supply. This situation raises concerns about grid stability, as any significant mismatch between demand and supply could lead to power cuts and blackouts. To address these challenges, India is focusing on reducing emissions from coal-fired power plants rather than phasing out coal entirely. A recent report from the Centre for Science and Environment (CSE) suggests that decarbonizing coal-based thermal plants could reduce greenhouse gas emissions by 30%. This aligns with India’s commitment to decrease emissions intensity by 45% by 2030 under international climate agreements. Strategies for Emission Reduction Experts propose several strategies to enhance the efficiency of thermal plants and reduce emissions. One approach involves improving the operational efficiency of these plants, allowing them to run at lower capacities without compromising electricity supply. Ramesh Veeravalli from India’s Central Electricity Regulatory Commission noted the technical feasibility of lowering the minimum running capacity of thermal plants. Additionally, adopting carbon capture technologies could help mitigate emissions, although current methods capture only a small fraction of global emissions. Another innovative solution involves substituting coal with agricultural residues in thermal plants, a practice that has shown promise in reducing coal usage in regions like Delhi. However, widespread adoption of this method across the country remains limited.