Flue Gas Desulphurisation (FGD)

A study by the National Institute of Advanced Studies (NIAS), Bengaluru, has requested the Union Environment Ministry to roll back its 2015 policy mandating all of India’s 537 coal-fired. The study was commissioned by the Office of the Principal Scientific Adviser.

Key Recommendations:

• Roll back the 2015 policy that mandates all 537 coal-fired power plants in India to install Flue Gas Desulphurisation (FGD) units.
• Limit FGD requirements to plants that use imported coal or high-sulphur (>0.5%) domestic coal.

Current Scenario:

• Original deadline: 2018
• Current compliance: Only 8% of plants have installed FGD
• Revised deadlines: Extended to 2027, 2028, and 2029, depending on plant category

Rationale Behind NIAS’s Recommendation:

• 92% of the coal used in Indian plants has low sulphur content (0.3%-0.5%)
• Existing regulations by the Central Pollution Control Board (CPCB) mandate stack heights of at least 220 metres, helping disperse SO2 effectively
• Indian climate conditions aid dispersion, limiting local air quality impact
• A 2024 IIT-Delhi study found acid rain is not a significant issue in India

Environmental and Energy Impacts of FGD Installation:

• Would increase freshwater and power consumption at plants
• Projected to add 69 million tonnes of CO2 (2025–2030)
• Would only reduce SO2 emissions by 17 million tonnes

Alternative Focus Recommended:

• Shift regulatory focus from SO2 to Particulate Matter (PM) pollution
• Indian coal’s high ash content contributes significantly to PM levels

(Source: TH)