Lok Sabha Question No. 4602 (UNSTARRED), answered on 2025-08-21
Subject: Mitigation of Sulphur Dioxide Emissions
Ministry: POWER
Asked by: Shri Maddila Gurumoorthy

## GOVERNMENT OF INDIA MINISTRY OF POWER

## LOK SABHA UNSTARRED QUESTION NO.4602 ANSWERED ON 21.08.2025

## MITIGATION OF SULPHUR DIOXIDE EMISSIONS

## 4602. SHRI MADDILA GURUMOORTHY:

Will the Minister of POWER be pleased to state:

- (a) whether the Government has accepted the recent recommendation of the committee  led  by  the  Principal  Scientific  Adviser  to  withdraw  the  mandatory installation  of  Flue  Gas  Desulphurisation  (FGD)  units  in  all  coal-fired  thermal power plants and if so, the reasons for this rollback despite its risks on health and environment;
- (b) whether any alternative technologies or regulatory frameworks have been proposed  to  replace  FGD  systems  in  controlling  SO ₂ emissions  from  thermal power plants and if so, the details thereof; and
- (c) whether the Government is considering a differential policy for coastal and non-coastal thermal plants based on their access to cheaper alternatives like seawater-based FGD treatment and if so, the details thereof?

## A N S W E R

## THE MINISTER OF STATE IN THE MINISTRY OF POWER

(SHRI SHRIPAD NAIK)

- (a) to (c): Ministry  of  Environment,  Forest  and  Climate  Change  (MoEF&CC) notified  emission  standards  [including  Sulphur  Dioxide  (SO2)]  for  coal  /  lignite based  Thermal  Power  Plants  (TPPs)  vide  its  Notification  dated  07.12.2015. Further, MoEF&CC vide Notification dated 31.03.2021 prescribed for categorization of TPPs into the following 03 categories for compliance of emission standards:
- (i)  Category-A (Within 10 km radius of National Capital Region or cities having million plus population);
- (ii) Category-B (Within 10 km radius of Critically Polluted Areas or Non-attainment cities);

(iii) Category- C (Other than those included in Category A and B).

To meet the SO2 emission norms, Flue Gas Desulphurization (FGD) system is being installed in coal/lignite based TPPs.

The  SO2  emission  standards  prescribed  in  MoEF&CC  Notification  dated 07.12.2015 have been reviewed by the Central  Government taking into consideration  the  various  representations  received  regarding  exemption  or relaxation in timelines of these standards due to limited availability of technology providers, its techno-economic feasibility, negative impact of COVID-19 pandemic on supply chain, price escalation due to high demand and low supplies, low SO2 concentration in ambient air and heavy burden on consumers due to increase in electricity price etc.

Besides, the scientific studies conducted by independent research institutions regarding effectiveness & rationale behind these standards and its role in overall ambient air pollution of the region were also considered to evaluate the need of universal applicability and enforcement of these standards.

Various Stakeholders' consultation meetings among MoEF&CC, Ministry of Power  (MoP),  Central  Pollution  Control  Board  (CPCB),  O/o  Principal  Scientific Adviser  (PSA)  to  the  Government  of  India,  Central  Electricity  Authority  (CEA), Research Institutions were also held in the matter. The recommendations of the stakeholders' consultation meetings, including the meeting chaired by the PSA to Govt. of India, was also taken into consideration by MoEF&CC.

In view of above, MoEF&CC has issued a Notification on 11.07.2025 regarding applicability of SO2 emission standards along with timelines for compliance by TPPs and its details are given below:

- (i) TPPS declared to  retire  before  31.12.2030  shall  not  be  required  to meet  specified  standards  for  SO2  emissions  in  case  such  plants submit an undertaking to Central Pollution Control Board (CPCB) and Central  Electricity  Authority  (CEA)  for  exemption  on  ground  of retirement of such plant;
- (ii) the existing and under commissioning Category A TPPs shall comply with SO2 emission standards by 31.12.2027. Other Category A plants to be commissioned after 31.12.2027 will operate only after ensuring compliance of these standards;

- (iii) for all Category B Plants or Units, whether existing or upcoming, the applicability  of  SO2  emission  standards,  shall  be  decided  by  the Central  Government  based  upon  recommendations  of  the  Expert Appraisal Committee in charge of Thermal Power Projects as per the procedure laid in the Notification dated 11.07.2025;
- (iv) the SO2 emission standards shall not be applicable to all Category-C TPPs  subject  to  compliance  of  stack  height  criteria  notified  by MoEF&CC on 30.08.1990 and timeline for compliance of stack height criteria is 31.12.2029.

The category wise applicability of SO2 emission standards in TPPs have been decided based on detailed scientific studies and analysis of ambient SO2 concentrations  across  the  country,  including  areas  near  TPPs.  This  approach applies  the  precautionary  principle  for  controlling  and  abating  air  pollution  in densely populated and other air pollution sensitive areas, while also emphasizing on resource conservation by avoiding additional consumption of water, auxiliary power,  and  limestone,  and  avoiding  the  increase  in  carbon  footprint/CO2 emissions resulting from the operation of deployed control measures, as well as mining and transportation of limestone required for these measures.

In all cases where SO2 emission standards are not applicable, all such TPPs (irrespective of location) shall ensure compliance to stack height criteria notified by  MoEF&CC on 30.08.1990 governing SO2 emissions from TPPs to aid proper dispersion of pollutants and mitigate environmental impacts.

Further, TPPs are required to comply with emission standards within the prescribed time limits, failing which environmental compensation will be levied on the non-compliant TPPs.

The selection of technology for FGD installation is decided on the basis of cost  benefit  analysis  by  the  utility.  The  policy  regarding  FGD  installation  is irrespective of coastal and non-coastal thermal plants.

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