Presentation Title
A holistic view of energy
efficiency improvement
in power generation.
New technology,
renovation & modernization
and process improvement.
By
Name: Souvik Dutta
Designation: Dy Chief Engineer(Gen)
Date:26.08.11
A holistic view of energy efficiency
improvement in power generation.
New technology, renovation &
modernization and process improvement.
Solutions
New
Technology
Technology
Renovation &
Modernization
Process
Improvement
Solutions
Major Initiatives for higher efficiency……
Adoption Supercritical,
Ultra supercritical
Technology
Adoption of Combined
cycle Technology
Adoption of Integrated
Gasification Combined
Cycle (IGCC) Suitable
for Indian Coal
Adaptation Supercritical / Ultra supercritical Technology
Development of Ultra Mega
Power Projects (UMPPs) has
been identified as a thrust area in
order to increase plant efficiency.
These are very large sized projects with
supercritical technology, approximately
4000 MW each involving an estimated
investment of about Rs. 16,000 crore
each.
Adaptation Supercritical / Ultra supercritical Technology
Salient features of the Plant and Choice of Technology
• The Ultra Mega Power Projects would use Super Critical
Technology with a view to achieve higher levels of fuel
efficiency, which results in saving of fuel and lower greenhouse gas emissions.
• Flexibility in unit size subject to adoption of specified
minimum Supercritical parameters.
• Integrated power project with dedicated captive coal blocks
for pithead projects.
• Coastal projects to use imported coal.
Solutions
43%
Gross Efficiency, GCV Basis
42%
320/600/620
Pr/MST/RHT
41%
(800-1000 MW)
280/600/620
(800-1000
MW)
247/565/593
40%
(660/800 MW)
247/537/565
(660 MW)
39%
170/537/537
(500 MW)
Current
scenario
38%
‘00
‘02
Xth
Plan
‘07
XIth
Plan
‘12
XIIth
Plan
‘17
XIIIth
Plan
‘22
Heat Rate Improvement (%)
Heat rate Improvement Over The Years
14
12
10
8
6
4
2
0
P = 130 ata
MST = 537
RHT = 537
200 LMZ (1978)
P = 150 ata
MST = 537
RHT = 537
P = 170 ata
MST = 537
RHT = 537
200 KWU (1979) 500 KWU (1982)
P = 170 ata
MST = 537
RHT = 537
500 KWU Mod
(1998)
P = 170 ata
MST = 537
RHT = 565
500 High RH
(2006)
P = 247 ata
MST = 537
RHT = 565
660 SC
P = 247 ata
MST = 565
RHT = 593
660/800 SC
Parameters for Higher Efficiency……
Plant Type
Unit Size
(MW)
Main Steam Pr
(Bar)
Main Steam
(Temp 0c)
Reheat
(Temp 0c)
Notes
Sub critical
500
170
537
537
Common
practice in India
Low
Supercritical
660
247
537
565
India’s first
supercritical
station at
Mundra by Adani
High
Supercritical
660/800
247-280
565
593
Parameters for
Mundra Tatapower
Ultra
Supercritical
1000
295
600
600
In operation in
Japan/China
Ultra Mega Power Projects : Indian Scenario
Projects under
process
Concerns: Viability at agreed upon
tariff due to changed scenario of
imported coal
Orissa
Integrated
Power Ltd
Akaltara
Power Ltd
Coastal
Karnataka
Power Ltd
Coastal
Tamil Nadu
Power Ltd
Tatiya
Andhra Mega
Power Ltd
Sakhi Gopal
Integrated
Power Co
Ltd Orissa
Gogarapalli
Integrated
Power co Ltd
Orissa
Coastal
Maharashtra
Mega Power
Ltd
Ultra Mega Power projects awarded through tariff based
competitive bidding route.
Plants have higher operating parameters and increased
efficiency levels.
Name of project
Name of
Date of LOI
Levelised
& capacity as per
successful
Tariff(Rs/Kwh)
LOI
bidder
Mundra
Gujrat(5X800 MW)
M/S Tatapower Ltd
28/12/06
2.26
Sasan M.P(6X660
MW)
M/S Reliance Power Ltd
01/08/07
1.19
Krishnapatnam
Andhra
pradesh(5X800 MW)
M/S Reliance Power Ltd
30/11/07
2.33
Tilya
Jharkhand(6X660
MW)
M/S Reliance Power Ltd
12/02/09
1.77
Ultra Supercritical
1000 MW units in
China
WAIGAOQIAO THERMAL
POWER STATION
PHASE-III:2X1000MW
SHANGHAI, CHINA
Adoption IGCC (Integrated gasification combined cycle)
Technology
An integrated gasification combined cycle (IGCC) is a technology that
turns coal into gas—synthesis gas (syngas).
Excess heat from the primary combustion and generation is then passed
to a steam cycle, similarly to a combined cycle gas turbine.
This then also results in improved efficiency compared to conventional
pulverized coal.( 46% to 52%)
In the IGCC plants, the production of CO2 during the gasification process
offers the opportunity for relatively low-cost CO2 capture and storage
(CCS), which may give the future IGCC plants some competitive and
environmental advantages over super critical plants
IGCC (Schematic diagram of the process)
IGCC (Schematic diagram of the process)
COOLED GAS
AND GAS COOLING
CYCLONE
NITROGEN
COMBUSTOR
DUST
FILTER
COAL
PRESSURISATION
LOCKHOPPER
STEAM
STEAM
TURBINE
ALTERNATOR
TURBINE
AIR
DRIED
ASH/ CHAR
COAL
COMPRESSOR
AIR
BUFFER / WEIGHING
HOPPER
TO STACK
CLEANED
GAS
BOILER
COAL DRYING
CONDENSER
WATER PUMP
EXHAUST GASES
AIR
STEAM
TURBINE
CO2
ASH/ CHAR
HEAT
HOT GAS
GAS
TURBINE
DRYER
GASIFIER
CLEANING
RECOVERY
IGCC
Efficiency and reliability improvements are also expected for
the IGCC technology. Its efficiency is estimated to grow from
46% in 2010 to 52% in 2020.
Some major IGCC plants, worldwide
580 MW, Kentucky Pioneer Energy, USA
512 MW, ISAB Energy, Italy
342 MW, Nippon Oil Corporation Refinery, Japan
335 MW, Elcogas, Spain
250 MW, Tampa Electric Company, USA
IGCC
India first IGCC power plant is coming up at
Vijayawada, foundation for which has been laid.
The 125 MW plant will be built in the premises of
Vijayawada Thermal Power Plant (VTPS).
BHEL and APGENCO has jointly funded this
project.
The main constraint of IGCC technology is cost
(+35%), more land requirement and higher
auxiliary consumption for producing syn gas.
250 MW IGCC plant: Tampa Electric Company, USA
Solutions
Renovation and Modernization (R&M) as
per CEA guidelines
Increase in availability and plant load factor of thermal power stations
Renovation and modernization for achieving higher efficiency levels.
Setting minimum acceptable standards & plan for R&M for projects below
standard with clear cost benefit analysis
If economic operation does not appear feasible through R&M, then there
may be no alternative to closure of such plants as the last resort.
In cases of plants with poor O&M record a change of management may
to be considered so as to improve the efficiency to acceptable standards.
NEED FOR R&M – EXISTING UNITS
Improvement in performance parameters – PLF,
availability, heat rate/efficiency, auxiliary power
consumption, partial loading & forced outage.
Restore derated capacity
Extension of economic life.
Obsolescence & non availability of spares (eg C&I)
Environmental issues/other statutory requirements.
Safety requirements.
FUTURE APPROACH TOWARDS R&M
NEAR PAST
In-kind replacement
Restoration of lost capacity
FUTURE
Cost effective technology upgrades
Uprating of capacity
Attain design efficiency
Improve upon design Efficiency
Reactive R&M
Pro-active R&M
From Time based R&M
Condition Monitoring & R&M
Optimisation through cost
benefit evaluation
R&M and Life extension program (LEP) during 11th
plan(2007-11)
Sl No
Particulars
R&M
LEP
I
Number of
thermal power
stations
21
23
Ii
Number of thermal
units
76
53
Iii
Estimated cost in
Rs crores
4487
12433
iv
Total capacity
involved
18965
7318
INDIA: Power generation Capacity in MW as
on 30th June 2011. Source: CEA website.
Capacity in MW as on 30th June 2011. Source: CEA website.
180000
176.99
Billion watts
160000
140000
120000
54.66%
100000
96.74 Billion
watts
MW
80000
21.53%
60000
10%
40000
0.68%
20000
11.02%
10.43%
2.7%
0
Coal
Gas
Diesel
Neuclear
Hydro Renewable
Source of power
Total
Captive
INDIA: Power generation Capacity (Billion Watts)
for Coal/Lignite based plants >25 MW capacity
Results of R&M
96.74
100
90
80.44
74.91
80
65.93
70
58.59
60.65
61.15
67.78
69.89
70.56
62.72
60
50
40
30
20
10
0
20002001
20012002
20022003
20032004
20042005
20052006
20062007
20072008
20082009
20092010
Jun-11
Year
2009-2010
77.68
77.22
78.75
80
2008-2009
77.03
78
2007-2008
2006-2007
73.71
74.84
76
2005-2006
2004-2005
72.96
72.34
74
2003-2004
2002-2003
PLF %
69.97
68.74
70
2001-2002
2000-2001
National Thermal plant performance (Coal
lignite based>25 MW) (PLF)
Results of R&M
72
68
66
64
62
Year
2010-2011
2009-2010
84.24
85.1
85.05
84.76
Results of R&M
2008-2009
83.72
86
2007-2008
81.78
85
2006-2007
2005-2006
82.93
84
2004-2005
81.93
81.83
83
2003-2004
2002-2003
79.91
PAF %
2001-2002
79.84
81
2000-2001
National Thermal plant performance
(Coal /lignite based>25 MW) (PAF)
82
80
79
78
77
Year
2009-2010
2008-2009
8.17
8.4
2007-2008
8.34
8.33
8.29
8.44
8.6
2006-2007
2005-2006
2004-2005
2003-2004
8.57
8.53
8.8
2002-2003
9
8.72
9.05
9.01
9.2
2001-2002
Aux %
2000-2001
National Thermal plant performance
(Coal /Lignite based>25 MW) (Aux%)
Results of R&M
8.2
8
7.8
7.6
Solutions
Process parameters to be improved……
Auxiliary power consumption
Heat rate
Oil figure
Plant load factor
Plant availability factor
Reduction of Auxiliary power consumption
Southern Generating Station.
CESC Ltd
Commissioning of Variable Frequency
Drives for U#2 ID Fans in February 2011
Objective: To reduce auxiliary power consumption
VFD ESSENTIALS
Make: Leader & Harvest Electric Technologies Co. Ltd, China
Indian Partner: Yantra Harvest Energy Pvt. Ltd, Pune
Product : Medium-Voltage VFD
Model: HARSVERT – A06.6/50
Rated Input Voltage: 6.6 KV
Rated Capacity: 450 KW
Rated Output Current : 50 A
Output Frequency Modulation: 0-50 Hz
Output Voltage Modulation: 0 – 6.6KV
Control Mode: Sinusoidal multi-level Pulse Width Modulation
VFD ESSENTIALS
Harvest MV Drive consists of
Input Transformer
Power Cell
Control System
VFD ESSENTIALS
Multi-winding Phase Shifting Input Transformer (Dry-type) comprising of
18 nos. Secondary (6 Per phase with Phase-shifted at 20,10,0,-10,-20
Degrees for 36-pulse rectification) & 1 no. Auxiliary Winding for Supply
to Cooling Fans of Power Cabinet
Primary Winding Rating : 6600V / 49.4 A
Secondary Winding Rating: 710V / 25.5 A
Auxiliary Winding Rating : 380 V/ 12.2 A
The Equipment
ID fan reduction in auxiliary power
consumption after installation of VFD
Unit Load
Particulars
Pre-VFD
period
Post-VFD
period
ID fan
370 KW
Payback
for two fans:18
to 229
20 KW
average
months
load (KW)
Full load
Net savings
per fan
133.5 KW
75 MW
AC load
(KW)
NIL
7.5 KW
36 % savings
Part load
ID fan
average
load (KW)
335 KW
159 KW
168.5 KW
NIL
7.5 KW
50-55 MW
AC load
(KW)
Note: Above Readings are in winter months.
Expected AC Load in Summer : 25 KW
50 % savings
Forthcoming VFD projects in CESC Ltd
in the current financial year.
Southern Generating Station:
Installation of four numbers VFD’S for two ID fans &
two FD fans of Unit no 1. Project: cost 410 lakhs.
Titagarh Generating Station:
Installation of VFD,S for two ID fans in one unit.Project
cost: 200 Lakhs
Southern Generating Station.
CESC Ltd :Micro Hydle project
Basic concept
Southern Generating Station.
45 KW(3x15 KW) Micro Hydel Project ph-1
Supplier: Pentaflow Hydro Engineers.Delhi
Specifications of the 15KW micro hydle turbine generator set
• Rated capacity: 15KW (At Generator output)
• Rated net head: 1.8 m
• Rated discharge: 1 m3/s
• Type of turbine: Propeller 4 blade inverted siphon
• Rated turbine speed: 360 rpm
• Runner diameter: 1000 mm
• Type of generator: Induction
• Method of drive: Flat belt
• Turbine efficiency: 86%
Southern Generating Station.
CESC Ltd
Commissioning of phase -1 of the project
completed in February 2011
Average 12-14 KW is being generated from
the first 15 KW unit
In subsequent phases another two such
sets will be commissioned
Auxiliary Energy Saved
Electricity saved each year considering import for 75% time of
a day for 350 days in a year
15 KW X 8400 hrs/year X0.75= 94500 KW-h / Year
This is equivalent to a savings of Rs 435000 / year
With a project cost of Rs 14.3 lakhs/unit payback is
approximately3.3 years
In the subsequent years other than minor maintenance costs
100% savings will be achieved
For three such units the projected savings will be
approximately Rs 10 lakhs
Micro hydle during
installation
Thank You !