Sulphur-cleaning device in coal plants not necessary

Context

• FGD (Flue Gas Desulphurisation) units are used to reduce sulphur dioxide (SO₂) emissions from coal-fired thermal power plants (TPPs).
• These were made mandatory in 2015 as part of stricter environmental norms.
• Despite repeated extensions, 92% of India’s 600 units still haven’t installed FGDs.

Relevance : GS 3(Environment an dEcology)

Committee Recommendation

• High-powered expert committee chaired by PSA Ajay Sood recommends FGDs are unnecessary for 80% of plants.
• Suggests FGDs be mandatory only in Category A plants:
  • Within 10 km of NCR and cities with 1 million+ population.
  • Out of 66 such plants, only 14 have FGDs installed.

Scientific Rationale Behind the Recommendation

• Ambient SO₂ levels across India are between 10–20 µg/m³, well below the national standard of 80 µg/m³.
• Indian coal is naturally low in sulphur content.
• Cities with FGDs and without FGDs show negligible difference in ambient SO₂ levels.
• SO₂ levels in general do not exceed permissible limits, hence do not justify nationwide FGD installation.

Operational & Economic Considerations

• High capital costs and few vendors for FGD installation.
• Potential rise in electricity tariffs if cost passed to consumers.
• COVID-19 disruptions cited as a reason for delays in FGD compliance.
• Historical deadline extensions by the Ministry of Power due to implementation hurdles.

Environmental Compliance

• Committee clarifies:
  • TPPs must still meet standards for:
    • Particulate Matter (PM) emissions.
    • Freshwater consumption.
  • SO₂ stack emission limits can be relaxed, as long as National Ambient Air Quality (NAAQ) standards are met.
• NAAQ standards, not stack norms, are the primary metric for protecting public health.

Institutions Involved

• Reports considered from:
  • CSIR-NEERI
  • National Institute of Advanced Studies
  • IIT Delhi
• All supported the view that FGDs are not essential across all plants.

Policy Implications

• Marks a major reversal of India’s 2015 emission control policy.
• Likely cost savings for power producers, but raises concerns over long-term air quality safeguards.
• Reflects a shift towards region-specific environmental regulation rather than blanket norms.