Dr. B. Sengupta

Former, Member Secretary

Central Pollution Control Board

Ministry of Environment & Forests

Govt. of India, Delhi

Email: bsg161@gmail.com,

9810043771

Presented at International Conference organised by NTPC on 13 Feb, 2012

at Le Meridien, Delhi

ENERGY IN INDIA : AN OVERVIEW

Energy demand driven by GDP, population and higher

urbanisation

India’s economy expected to grow by 7-8%

Population expected to touch 1.32 Billion and

Urbanisation levels is expected to touch 43% by 2020.

Energy per capita at 345 Kgs per capita is low vis-à-vis

a Global Average of 1624 Kgs.

By 2020, India’s energy per capita is expected to touch

722 Kgs per capita.

Increasing environmental concerns will play a role in

determining the fuel mix.

Switch from Traditional Fuels, further impetus to

commercial energy.

Indian Power Sector

Source: Ministry of New and Renewable Energy

Energy Scenario in India

Rapid economic development & Increasing

population = High demand for Energy

A sustained 8% GDP growth of India requires an

annual increase of:

a) Commercial energy supply from 3.7% to 6.1%

b) Total primary energy supply from 2.2% to 5.1%

Limited supply of COAL, coupled with its poor quality,

low level of technologies advancements and high

environmental hazards.

Limited domestic reserves and uncertain foreign

supply of hydrocarbons.

Rapidly Growing Energy Demand

Estimated

Commercial Energy

Demand

Million Tonne Oil

equivalent

2002 2010 2020

Demand 345 547 882

Coal 185 281 397

Oil 113 175 263

Gas 27 59 170

Others 20 32 51

Hydrocarbons account for a major share of the fuel mix.

Status of Oil Sector

Domestic Production is much lower than Demand

Production is stagnant and no major discoveries of

oil since Bombay High (except Rajasthan field).

Middle East and West Africa meet India’s major

crude requirements.

Emerging Oil Demand Supply Scenario

2002 2010 2020

Oil Demand 113 175 263

Production 33 45 50

Imports 80 130 213

Import Dependence 71% 74% 81%

Reduced dependence on oil imports necessary to

enhance energy security

Status of Natural Gas Sector - I

Gas demand would largely be driven by its higher efficiency and lower

GHG emissions vis-à-vis other fuels.

India has total gas reserves of 30 TCF.

Globally gas accounts for 23% of energy while in India it accounts

for 8% of the energy Mix.

Gas Demand would largely find applications in the power sector.

India plans to more than treble its installed capacity from 100 GW to

341 GW by 2020.

A significant portion of this incremental capacity would be driven by

gas.

In addition Gas Demand would be driven by CHP applications and

city gas distribution projects.

Investments in pipeline infrastructure is critical for optimal

utilisation of gas.

Recent gas discoveries alleviate imports but growing demand may

outpace supply.

Status of Natural Gas Sector - II

Gas Demand Supply Million Tonnes of Oil

Equivalent (MMSCMD)

2002 2010 2020

Gas Demand 27(82) 59(179) 170(517)

Imports / New Finds 0 36 (110) 143 (435)

Existing Production 27(82) 23(69) 27(82)

Imports as % of total 0% 61% 84%

Possible Mix of New Gas Supply MMSCMD (2020)

Domestic Conventional 100 – 150

Domestic CBM/UCG 50 – 75

LNG / Cross Border Pipelines 175 – 250

Rising supplies incommensurate with growing demand

Status of Coal Sector - I

Indian Coal is high in ash and low in calorific value

Globally coal accounts for 24% of energy while in

India it accounts for 54% of the energy Mix.

Coal Demand largely driven by demand from Power,

Steel, Cement Sectors.

India has proved reserves of coal estimated at 84

billion tonnes.

However India’s productivity levels are relatively low

as compared to other nations.

Hence investment is required to modernize coal

mining facilities.

India also needs foreign capital in the emerging areas

of Coal Bed Methane and UG Coal Gasification.

Status of Coal Sector - II

Coal Demand Supply Million Tonnes of Oil

Equivalent (MT of Coal)

2002 2010 2020

Coal Demand 172 (367) 254 (543) 395 (842)

Imports 13 (24) 59 (118) 95 (190)

Coal Production 159 (343) 195 (425) 300 (652)

Imports Dependence 8% 23% 24%

Massive investment required for

modernization / new capacity addition

FUEL SHARE FOR POWER GENERATION ( %)

Ist Plan (1956) VIth Plan (1990)

Nuclear 2%

Thermal 69%

Hydro 29%

2010 Projected (2012)

Hydro 25.9%

Thermal 66.0%

Nuclear 3.1%

Renewable 5.0%

Hydro 35%

Thermal 65%

Nuclear 4.6%

Thermal 66.2%

Hydro 29.2%

GROWTH IN POWER GENERATION (YEARWISE)

17

12

46

55

12

55

7 28

44

8

66

00

3

97

38

6

10

16

61

10

58

34

10

78

77

11

45

09

12

42

72

0

20000

40000

60000

80000

100000

120000

140000

1950

1960

-61

1968

-69

1979

-80

1990

-91

1999

-200

0

2000

-01

2001

-02

2002

-03

2003

-04

2005

-06

Ins

talle

d c

ap

ac

ity

(M

W)

PER CAPITA ELECTRICITY CONSUMPTION

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

Per

cap

ita

con

sum

pti

on

(kW

H)

Indi

a

Bra

zil

Chi

na

Pak

Egy

pt

Aus

tral

ia

UK

USA

Air Pollution Due to Use of Coal in Thermal Power Plants

ITEMS EXISTING SCENARIO

2050

SCENARIO

Coal based Electricity Production (MW)

67600 900000

Coal Consumption

(million tonnes)

258 3434

Particulate Matter Emission (million tonnes)

1.62 21.9

Sulphur Dioxide

(million tonnes) Emission

2.451 32.6

Oxide of Nitrogen

(million tonnes)

2.3 30.9

Source: CEA/NTPC

Use of clean coal technologies (Super Critical ,IGCC, PFBC, CFBC, etc.) to be promoted based on location specific requirements.

USE OF BENEFICIATED COAL

Ministry of Environment & Forests, vide notification no. GSR 560(E) & 378(E) dated September 19, 1997 and June 30,1998 respectively made mandatory use of beneficiated/blended coal containing ash not more than 34 per cent on annual average basis w.e.f. June 2001 (extended to June, 2002) in following category of power plants

Power plants located beyond 1000 km from pit head Power plants located in critically polluted areas, urban

areas and ecologically sensitive areas.

The Power Plants based on FBC (CFBC, PFBC & AFBC) & IGCC technologies are exempted to use beneficiated coal irrespective of their locations.

POWER SECTOR (COAL) : A PROFILE

Sixty Six per cent of electricity production is based on coal and gas in the country.

81 coal based thermal power plants with total generation capacity of 90000 MW (approx)

16 gas/naphtha based power plants with total generation capacity of 12705 MW

More than 258 million tonnes of coal with ash content 35-45% was consumed by the Thermal Power Plants

Nearly 190 million tonnes per annum coal ash is generated.

More than 25,000 hectares of land has been occupied for conventional disposal of ash.

More than 630 million M3 water is required for disposal of coal ash as in slurry form per annum

ENVIRONMENTAL PROBLEMS

Use of high ash content coal in power generation leads to the following environmental problems: AIR POLLUTION

• Emission of particulate matter (dust) • Emission of sulphur dioxide and Oxides of Nitrogen • Green House Gas Emissions • Emission of Mercury (both gaseous and in ash) • Fugitive emission of suspended particulate matter from CHP, Wagon

Tripler and ash pond

WATER POLLUTION

• Cooling water discharge • Ash pond effluent

SOLID WASTE

• Large volume of coal ash generation (Flyash & Bottom ash) • Large land requirement for ash disposal

PARTICULATE MATTER EMISSION ESTIMATES

Total load = 5365 tonnes/day

Thermal

Power Plants

82%

Others

1%

Sugar

10%

Cement

7%

SHARE OF SULPHUR DI-OXIDE EMISSION LOAD (TONNES/DAY)

FROM DIFFERENT CATEGORIES OF INDUSTRIES

Total load = 3715 tonnes/day

Thermal Power Plants 89%

Oil Refineries 3%

Others 1%

Steel 5% Sulphuric acid

Plant 2%

GREEN HOUSE GAS EMISSIONS

India ranks 20th in the world for CO2 emissions

Total CO2 emissions in India have increased by 47.7% from 1990 to 1996

Pollutant gm/KW

H

Tonnes/day Million

tonnes/annum

CO2 997 1088436 363

SO2 6.9 7542 2.5

NOx 0.47 519 1.7

Soot (Carbon) 0.055 60 0.2

GHG emissions from coal fired power plants ( Base year 1997)

TOTAL AND PER CAPITA CO2 EMISSION

0

5000

10000

15000

20000

25000

World USA EU

India

China

Brazil

Japan

Germ

any

Mill

ion

to

nn

es

0

5

10

15

20

25

Mil

lion

ton

nes

Total CO2 emission

CO2 Emission (per capita)

ENVIRONMENTAL REGULATIONS

To achieve uniform coal quality, effective compliance & proper management of solid waste(Flyash) following regulations have been stipulated :

Use of Beneficiated/Blended Coal

Emission standards for Particulate Matter

Stack Height Requirement

Effluent standards

Flyash Utilisation

EMISSION STANDARDS FOR THERMAL POWER PLANT

Depending upon the requirement of local situations, which may warrant stricter

standards as in case of protected areas the State Pollution Control Boards and other

implementing agencies within the provisions of the EPA, 1986 may prescribe limit of 150

mg/Nm3 irrespective of the generation capacity of the plant.

Power generation Capacity

(MW)

Particulate matter

emission

Less than 210 MW 350 mg/Nm3

210 MW or more 150 mg/Nm3

STACK HEIGHT REQUIREMENT For proper dispersion of SO2 emissions from thermal power plants,

stack height criteria has been prescribed. However, for larger

capacities of boilers (500 MW and above), space provision for

installing FGD system is recommended.

Power generation Capacity Stack height (metre)

Less than 200/210 MW

200/210 MW or less than

500 MW

500 MW and above

H= 14(Q)0.3 where Q is

emission rate of SO2 in kg/hr

and H is stack height in metre

220

275

EFFLUENT STANDARDS Process Parameter Concentration (mg/l)

Boiler Blow Down SS 100

Oil & Grease 20

Copper(total) 1.0

Iron(Total) 1.0

Condenser Cooling Water

(Once Through Cooling)

pH 6.5-8.5

Temperature 10oC above the intake water

Free available

chlorine

0.5

Cooling Tower Blow Down Free available

chlorine

0.5

Zinc 1.0

Chromium 0.2

Phosphate 5.0

Ash Pond Effluent pH 6.5-8.5

SS 100

Oil& Grease 20

Compliance Status

As on March 2006

Number of plants complying with Emission

standards

63

Number of plants complying with Effluent

standards

73

Total number of plants 78 ( 5 plants are closed)

IMPLEMENTATION OF ENVIRONMENTAL STANDARDS (EMISSION

& EFFLUENT) IN NON- COMPLIANT POWER PLANTS

Measures taken

Adoption of Flue Gas conditioning (Ammonia,

Sulphurtrioxide))

Retrofitting /augmentation of ESPs in time bound manner

Ash dyke raising / recalculation of ash pond effluent/dry

flyash collection

REASON FOR NON-COMPLIANCE OF ENVIRONMENTAL

STANDARDS IN COAL BASED THERMAL POWER PLANTS

High ash content in coal used in power plants

Poor ash chemistry: high silica,high alumina, low sulphur & low sodium

High resistivity of coal

Inconsistent supply of coal

Low calorific value

Delay in supply/installation of ESPs

Low design efficiency of ESP( low SCA)

Poor operation & maintenance of ESPs i.e. timely replacement of faulty parts such as

hanging electrodes

Non installation of state of Art EPIC controllers

In sufficient water pressure below the ESP hoppers

Rapping time not optimum

Inefficient management of ash ponds

Paucity of funds

INITIATIVES TAKEN FOR MITIGATION OF

ENVIRONMENTAL PROBLEMS

To minimize the impact of emission of particulate matter and

other Green House Gases following measures have been

taken:

Use of beneficiated coal

Promoting utilisation of flyash

Adoption of clean coal combustion technologies

Clean Coal Combustion Technologies To reduce emission of GHG, NOx, SO2 & enhance thermal efficiency by adopting clean technologies

1. Super Critical Technology

Larger unit size (more than 500 MW)

Higher thermal efficiency

Low gaseous & soot emissions

2. Fluidised Bed Combustion (CFBC/PFBC/AFBC)

Can burn wide range of coals and other fuels such as pet coke, lignite etc.

Higher thermal efficiency (>40%)

Low NOx emissions

Low CO2 emissions

In-situ SO2 control

Sizes upto 250 MW commercially available indigenous

3. Integrated Gassification Combined Cycle (IGCC)

Limitation on availability of larger unit size

High thermal efficiency (>45%)

Sulphur dioxide removal upto 99%

NOx reduction by 90%

Low CO2 emission

4. Post Combustion Technologies

High efficiency electrostatic precipitator

De SOx and DeNOx systems

Recycling of ash pond effluents

Switching over to medium concentration slurry disposal system (MCSD)

with ash concentration in slurry 40-45% and high concentration slurry

disposal systems (HCSD) with ash concentration in slurry 65-72%

Cont’d

Clean Coal Combustion Technologies

Current Environmental Challenges in Coal based Power Station in India

Compliance of emission standard stipulated under EP Act in TPP (PM standard, Stack Height criteria, FGD condition in some cases etc.)

Compliance of effluent standard stipulated under EP Act in TPP (specially to comply zero discharge)

Compliance of Fly Ash Rules stipulated under EP Act in TPP (Transportation of dry fly ash to cement plant, mine-back filling, brick making, raising of ash dyke etc.)

Compliance of New Ambient Air Quality Standard notified under EP Act and Air Act (parameters to be monitored, frequency of monitoring, data reporting)

Parameter under Water Quality Standard to be monitored by TPP

Continuous Stack and Ambient Air Quality Monitoring by TPP and Data posted at website (calibration of analyser, sampling protocol, data reporting etc.)

Contd..

Obtaining EC under EP Act, 2006 (coal linkage, land for ash pond, forest clearance, water availability, COC etc.)

Baseline data generation for EIA preparation (biodiversity study, baseline air quality data, hydro-geological data, zero discharge etc.)

Non-compliance of EC Condition (Serious Violation Cases)

Fugitive emission control from TPP (coal yard, fly ash storage area etc.)

Mercury emission and its control from TPP

Adoption of clean coal technologies in TPP

Implementation of coal beneficiation regulation in TPP

GHG emission reduction from TPP

Recent MoEF circulars and its interpretation

Current Environmental Challenges in Coal based Power Station in India (contd..)

Specific conditions imposed by MoEF under EIA 2006 while granting Environmental Clearance to

Coal based Power Station

A. Air emission management

Particulate Matter (PM) emission to be restricted to 50 mg/nm3

Exit gas velocity should not be less than 22 m/s

Baseline air quality data to monitor for PM10, PM2.5, SO2, NOx, Hg, O3 etc.

Large plant (660 MW and above) should be based on super critical technology

Continuous monitoring system for PM, SO2, NOx to be installed

Space for FGD to be kept. In some recent cases FGD condition is kept mandatory for SO2 control Contd..

B. Ash Management

Ash utilization as per Fly Ash Management Notification, 1999 and its amendment in 2003 / 2009 (within 4/5 years 100 percent utilization of fly ash [ESP ash])

Ash pond shall be lined with HDPE / LDPE lining or any other suitable impermeable matter so there is no leaching of heavy metals to ground water

Adequate safety measures should be undertaken to protect the ash dyke from getting breached

Hg and other heavy metals (As, Cr, Pb, etc) shall be monitored in the bottom ash

Coal transportation only by rail and no road transportation of coal

Contd..

C. Waste Water management

COC of 5.0 shall be adapted. Close cycle cooling system with cooling tower should be adapted

Ash pond water to be 100% re-circulated

D. Green belt development

Green belt consisting of 3 tier of plantation of native species around the plant of 100 m width shall be raised. The density of tree shall not be less than 2500 per hectare and rate of survival should be atleast 80%

E. R & R issue

R & R plan as per guideline should be implemented

Wildlife conservation plan (if in forest or grazing land) to implemented

Non Compliance of EC Conditions, Categorization of Conditions as Serious and Not So Serious for Thermal Power Plants

Sl.

No.

EC Conditions Non compliance

of EC Conditions

Serious Not so

serious

1. Status report for implementation of 100% utilization of Fly

Ash generated shall be submitted.

2. Stacks of prescribed height shall be provided with continuous

online monitoring equipments for SOx, NOx and Particulate

matter. Exit velocity of flue gases shall not be less than

prescribed limit. Mercury emissions from stack shall also be

monitored on periodic basis.

3. Regular monitoring of ground level concentration of SO2, NOx,

RSPM and Hg shall be carried out in the impact zone and

records maintained. If at any stage these levels are found to

exceed the prescribed limits, necessary control measures shall

be provided immediately.

Contd..

4. High Efficiency Electrostatic Precipitators (ESPs) shall

be installed in each unit to ensure that particulate

matter (PM) emission does not exceed stipulated

standard.

5. Adequate dust extraction/suppression system shall be

installed in coal handling, ash handling areas, and

conveyer belts to control fugitive emission.

6. Space provision be made for Flue gas De-sulphurisation

(FGD) unit, if required at a later stage to control SO2.

7. Low NOx burner shall be provided to reduce the NOx

emission.

8. Noise levels emanating from turbines shall be

controlled to ensure compliance to standards for

workzone. People working in the high noise area,

should be provided with requisite personal protective

equipment like earplugs/ear muffs etc.. Workers

engaged in noisy areas shall be periodically examined to

maintain audiometric record and for treatment for any

hearing loss including shifting to non-noisy/less noisy

areas.

Contd..

9. Fly ash shall be collected in dry form and ash generated

shall be used in phased manner as per provisions of the

Notification on Fly Ash Utilization. Unutilized ash shall

be disposed off in the ash pond in the form of High

Concentration Slurry. Mercury and other heavy metals

(As, Hg, Cr, Pb, etc.) will be monitored in the bottom ash

as also in the effluents emanating from the existing ash

pond. No ash shall be disposed off in low lying area.

10. Base line health data within study area shall be

collected and prepared. Mitigation measures should be

taken for control of endemic diseases.

11. Ash pond shall be lined with impervious lining as per

the soil conditions. Adequate safety measures shall also

be implemented to protect the ash dyke from getting

breached.

12. Impact on agricultural crops (as applicable) due to

operation of the power plant shall be studied from an

institute of repute within six months. The study shall

also include impact due to heavy metals associated with

emission from power plant.

Contd..

13. Regular monitoring of ground water in and around the

ash pond area including heavy metals (Hg, Cr, As, Pb)

shall be carried out. The data so obtained should be

compared with the baseline data so as to ensure that

the ground water and surface water quality is not

adversely affected due to the project.

14. A conservation plan for wildlife as stipulated, shall be

prepared in consultation with an expert organization

and duly approved by State Wildlife Department.

15. The industry should comply with the general effluent

standards.

16. CFBC Technology with lime injection for removal of SO2

up to 70% shall be provided.

17. The total water drawal from River for all units should

not exceed the requirement as stipulaed.

Contd..

18. Hot water coming from the condenser should be

properly cooled so as to ensure to keep the temperature

of the receiving surface water as per the standards.

19. Ash pond shall be lined with impervious lining as per

the soil conditions. Adequate safety measures shall also

be implemented to protect the ash dyke from getting

breached.

20. Plant should be designed for zero discharge. The treated

effluents emanating from the different plants such as

DM plant, boiler blow down, ash pond/dyke, sewage etc

conforming to the prescribed standards shall be re-

circulated and reused.

21. Closed cycle cooling (COC) system with cooling tower

shall be provided. Prescribed COC should be adopted.

22. Adequate safety measures shall be provided in the plant

area to check/minimize spontaneous fires in coal yard,

especially during summer season. Copy of these

measures with full details along with location plant

layout shall be submitted to the Ministry as per EC

conditions.

Contd..

23. Storage facilities for auxiliary liquid fuel such as LDO and

HFO/LSHS shall be made in the plant area in consultation with

Department of Explosives, Nagpur. Sulphur Content in the liquid

fuel will not exceed 0.5%.

24. First Aid and sanitation arrangements shall be made for the

drivers and other contract Workers during construction phase.

Natural Gas based Combined Cycle Power Plant 1. Dry Low NOx burners shall be provided and it shall be ensured

that NOx emissions from individual stack shall be limited to 50

ppm.

2. Closed cycle cooling system with cooling towers shall be provided.

COC of at least 9 shall be adopted and the effluent treated as per

the prescribed norms.

3. Adequate safety measures shall be provided to limit the risk zone

within the plant boundary, in case of an accident. Leak detection

devices shall also be installed at strategic places for early

detection and warning.

4. Regular mock drills for the on-site emergency management plan

specially pertaining to fire and explosion hazards due to use of

natural gas shall be carried out.

Major Environmental Issues 1. Implementation of fly ash notification (100% utilization

of fly ash in 4/5 years is a big challenge)

2. More use of fly ash in cement production and use of ash in mine back filling to be promoted

3. Condition of coal transportation only by rail is required to be reviewed

4. Condition of PM emission to be restricted to 50 mg/nm3 for new plants, require discussion

5. Implementation of coal beneficiation regulation require more attention of SPCB / CPCB and Ministry of Coal

Contd..

6. Any policy on Hg emission measurement / control require more discussion

7. Calibration of analyzer in Continuous Ambient Air Quality Monitoring Stations is a major challenge

8. FGD condition for SO2 control require more discussion

9. Ash dyke safety issue is an important aspect

CONCLUDING REMARKS

Considering huge demand of power (900,000 MW by 2050) to sustain 7-8 % GDP, lot of investment is required in the field of environmental friendly coal mining, emission of SO2, NOx, Hg control from coal based power station and ash utilization.

Clean coal technologies to be promoted in a big way to minimize the impact of pollution from coal based power station on environment and also to reduce GHG emission.

80 % of requirement of crude oil is required to be imported. Dependence on import of crude oil can be reduced by promoting alternate source of energy (bio-fuel, bio-diesel, Hydrogen etc)

Contd..

Natural gas and LNG are cleanest form of energy, however the availability is limited. KG basin gas production is required to be increased. Further large investment are required to be made to trap the coal bed methane, shell gas and gas hydrates etc.

Renewable source of energy specially wind power, solar power, mini hydro power, biomass based power plant, power from bio-methanation plant etc should be promoted in a big way.

Energy efficiency measures from power plants and other industry sectors should be promoted in a big way, in order to reduce pollution and GHG emission.

MoEF may review Fly Ash Rule, 2009 as it is very difficult to utilize 100% fly ash within 4 years

Presently 15% of dry fly ash are allowed to make fly ash pozzolona cement, it may be increased 25 to 30 % after doing proper study on clinker / cement quality

Mine back filling with fly ash is one of the best option for utilization of ash, this may be reviewed