FGD Exemption for Thermal Plants

• 16 Jul 2025

Source: TH 

The Ministry of Environment, Forest and Climate Change  has exempted 78% of India’s thermal power plants from installing Flue Gas Desulphurisation (FGD) systems, raising air pollution and public health concerns. 

• FGD Role: These are used to cut sulphur dioxide (SO₂) emissions from coal-based thermal power plants. FGD systems commonly use limestone (CaCO₃), lime (CaO), or ammonia (NH₃) as reagents to neutralize SO₂ in flue gases 
• Policy Shift: In 2015, it was notified that all thermal power plants must install FGD systems by 2017 to reduce SO₂ emissions. However, only about 8% of the plants have complied. 
  • As per the new notification, Only 11% of units (Category A) located in densely populated areas or within 10 km of National Capital Region are mandated to install FGD. 
    • Another 11% (Category B) near critically polluted areas or non-attainment cities may be required to install FGD, depending on expert committee review. 
• Key Reasoning Behind Rollback: A panel led by Principal Scientific Adviser stated that Indian coal has low sulphur content and that ambient SO₂ levels are already below permissible limits (10–20 µg/m³ vs 80 µg/m³ limit).  
  • It also found no significant difference in air quality between areas with or without FGD units.  
  • High installation costs, limited vendors, and delays due to Covid-19 were also cited as key reasons for exempting most thermal plants. 
• Expert Critique: SO₂ contributes to fine particulate matter (PM2.5), impacting health up to 200 km away. Lack of FGD could increase risk of respiratory and cardiovascular diseases. 
  • Tall chimneys only spread, not reduce, emissions. Coal combustion contributes around 15% of India’s PM2.5 levels. 
  • The decision lacks public debate, sets location-based standards, and risks harming air quality and health. 

Read more: Reviewing FGD Rules for Coal Power Plants