The study focused on winter, when cooler weather traps pollutants near the ground. Research shows Chennai’s PM2.5 levels rise 3–40 percent in winter, likely worse in Ennore due to industrial activity
Published Jul 16, 2025 | 3:45 PM ⚊ Updated Jul 16, 2025 | 3:45 PM
Ennore thermal plants violated pollution norms nearly 50% of winter days, says new study (JSW.in)
Synopsis: A new study by the Save Ennore Creek Campaign reveals that Ennore’s thermal power plants violated air pollution norms nearly 50% of the time between November 2024 and January 2025. Based on TNPCB data, the report highlights excessive emissions of particulate matter, SO₂, and NOₓ from NCTPS and NTECL Vallur plants, exposing regulatory lapses and health risks
A new study by the Save Ennore Creek Campaign has revealed that Ennore’s thermal power plants violated air pollution monitoring and emission norms nearly 50 percent of the time during the winter season between November 2024 and January 2025. The findings, based on real-time air monitoring data from the Tamil Nadu Pollution Control Board’s (TNPCB) CARE AIR Centre, expose a serious failure of environmental regulation and disregard for public health.
The analysis focused on NCTPS Stage I & II and NTECL Vallur plants—run by TANGEDCO and NTPC Tamil Nadu Energy Company Ltd. respectively—and shows extensive violations of permissible limits for key pollutants like particulate matter (PM), sulfur dioxide (SO₂), and nitrogen oxides (NOₓ).
The winter period was deliberately chosen for the study, as cooler weather conditions worsen pollution impacts by trapping pollutants at the ground level. Supporting this, recent research has shown that Chennai’s PM 2.5 levels during winter are 3–40 percent higher than annual averages, suggesting that Ennore’s local levels may be significantly worse due to the presence of thermal plants and other polluting industries.
The TNPCB, despite repeated court orders and policy assurances post the Coromandel gas leak protests, has failed to take regulatory action. Notably, in the fisher-led case (OA 8 of 2016) on Ennore ash pollution, the board was directed to monitor NCTPS operations and prosecute for violations—an order it has not acted upon.
Environmental activists allege that the board’s inaction, particularly in a region populated by Scheduled Castes, Scheduled Tribes, and Most Backward Classes, amounts to environmental casteism. The government’s failure to act is viewed as deliberate negligence toward marginalised communities living in a known pollution hotspot.
The thermal power plants are only part of the problem. The Ennore-Manali air shed includes other red-category industries such as:
A 2021 court-appointed committee noted that SO₂ emissions from these industries were 36 times above safe limits, identifying the region as overpolluted and recommending a moratorium on further industrial expansion.
Residents from Ennore’s fishing villages expressed anguish and desperation, “Many people, including children, have died of cancer in our village, and we cannot tolerate any more deaths in the name of pollution,” said Gnanambika of Kattukuppam, who lost her husband to cancer.
“We need a future free from choking. We have written a petition to the Environment Department and TNPCB to stop pollution in Ennore,” said a child from the region.
The study was conducted using online stack/chimney emission monitoring data from TNPCB’s CARE AIR Centre, focusing on:
The findings point to a clear pattern of emissions violations, incomplete data transfers, and a total lack of enforcement by the state pollution board.
Environmental groups are now demanding:
(Edited by Ananya Rao)
