SO₂ Mitigation from Coal Plants:
A comprehensive study by IIT Delhi, published in the Nature journal, reveals that India could prevent over 1.24 lakh annual deaths by fully mitigating Sulphur Dioxide (SO₂) emissions from Coal-Fired Power Plants (CFPP).
Key Findings of the Study:
- Rising Emission Trends: Contrary to global declines, India’s SO₂ emissions from CFPPs rose from 2.36 thousand kilotonnes (2005) to 5.05 thousand kilotonnes (2021), with a further 30% spike in 2023.
- Secondary Pollutant Formation: The study emphasizes that SO₂ emissions are a primary precursor to Secondary Inorganic Aerosols (sulphates, nitrates, and ammonium), which significantly contribute to PM2.5 levels.
- Geographic Hotspots: Maharashtra, Tamil Nadu, and Karnataka face the highest avoidable mortality due to population density, while Chhattisgarh and Odisha would see the most dramatic air quality improvements.
- Environmental Equity: The research utilizes National Family Health Survey-5 (NFHS-5) data to show that Scheduled Castes (SC), Scheduled Tribes (ST), and Other Backward Classes (OBC), along with lower-income groups, suffer disproportionately from CFPP pollution, making mitigation a matter of social justice.
- Technology Debate: The study advocates for the mandatory installation of Flue Gas Desulphurisation (FGD) systems, arguing that health-related monetary gains far outweigh the high costs of the technology.
- In July 2025, the Centre relaxed the 2015 emission norms, exempting nearly 79% of coal units from installing FGD systems.
- Policy Recommendations: Researchers call for strict enforcement of MoEFCC emission norms, prioritization of pollution hotspots, and a shift toward cleaner cooking fuels and electric vehicles.
