Transcript Slide 1

GENERATION
RENOVATION & MODERNISATION
R. K. Jain
Director (Technical)
NTPC Limited
India Electricity – 2006
11th May, 2006
INDIAN POWER SECTOR
•Present Status:
– Per capita consumption about 600 units per annum
– Installed Capacity 1,24,287 MW (April, 2006)
•India’s Projected Growth is 7-8 % of GDP – Projected power requirement by
year 2012:
– Per capita consumption 1000 units per annum
– Installed capacity over 2,00,000 MW
•Projected power requirement by year 2032:
– Per capita consumption about 3000 units per annum
– Installed capacity about 6,00,000 to 7,00,000 MW
However government of India is targeting double digit growth rate (10%) and
hence projections are likely to get revised upwards. The above necessitates :
• Sustainable Large Capacity Addition Program at higher efficiency
• Upgrading fleet of Old Power Stations which are inefficient and have
poor availability
R&M and Re-powering
•India has large number of old plants which are
inefficient and running below design capacity
•Operating pressure and temperature of these old
plants are lower and there is no reheating in some of
the units
•Fuel available at present is different from what
plant were designed for
•Some of the equipments have degraded
•Re-powering of these plant can quickly increase the
power generation at relatively lower cost to
consumer
•Re-powering can increase the cycle efficiency and
hence reduce emission of greenhouse gases and
pollutants
R&M and Re-powering
•R&M will involve up gradation of milling system, APH, ESP,
firing system etc and refurbishment of turbine, condenser,
pressure parts, fans etc.
•Re-powering may involve following changes in plant design :
• Adoption of higher steam parameters
• Introduction of topping cycle, old turbine may be
retained in bottoming cycle.
• Bottoming turbine cycle efficiency improvement by
adoption of high efficiency blade design
Thus, Renovation & Modernization of old existing units is an important
tool for capacity enhancement, life extension and improvement in
availability, reliability & efficiency.
Re-powering is challenging from technology as well as engineering point
of view and offers huge potential for capacity addition augmentation.
RATIONALE FOR R&M
•New Plants –costly.
•Longer gestation period of new plant.
•Limited availability of new site.
•Old plants can be renovated and Modernised at lower costs and life
extension achieved.
•Availability and efficiency can be improved.
•Minimum environmental impact and R&R problems for additional
capacity.
•R&M is an efficiency improvement tool and can improve generation
by 30%, environment impact by 47% and efficiency by 23% (Source:
TERI)
APPROACH TO R&M
Depends on
•Age of the plant, its existing condition and
generic problems in its inherited design
•Operational History & Problems being faced to
run the plant
•Major modifications carried out from the original
design condition
•Type of fuel & its cost
•To cater to changes in the input / output of the
plant – coal, water, power evacuation
•Source of availability of inputs for future
•Cost of generation
•Cost of Technology
WHY R&M?
•To restore the original rated parameters by one to one
replacements
•Improve performance by introduction of new technology.
•To upgrade the units to comply with fast changing
Environmental / statutory standards / guidelines.
•To cater to technological obsolescence.
•Mega R&M – Technology Upgrades. This would aim at both
leveraging the technological advancements, as well as driving
down the Cost Of Generation, while factoring in the emerging
business scenario to meet the market determined price for
power
Technological Options
 Clean Coal Technology
To reduce SOX ,NOX & CO2 Emissions
 Energy extraction from coal
1.PC fired
2.Fluidized bed combustion-Reduces Sox, NOx
Emissions
3.Indirect combustion through coal gasification
 Sub Critical Steam Parameters To Supercritical
Parameters
Increase in Pressure and temperature to like 250bar
and 565 deg C
 Re-powering Technology
For better efficiency, pollution control and less cost
besides life extension
Technological Options
BOILER & AUXILIARIES
Replacement/Augmentation Of Pressure Parts.
Retrofitting/ Modifications Air Pre Heater.
Augmentation Of Milling System.
Provision Of Flame Scanners, ignitors.
Renovation of Draft System.
Retrofitting Of ESPs.
Technological Options
TG & AUXILIARIES
 Replacement of turbine blades with latest
design.
 Modernization of condensors by change in
type and material of tubes, augmenting with
tube cleaning mechanism.
 Modernisation of power cycle equipments with
more efficient pumps and improved
Regenerative Heaters.
 Modification of air evacuation system with
Vacuum pumps.
Technological Options
Gas Turbine
Inlet Air Cooling system.
Online Compressor Washing System
Dry Low NOx Burners.
Improved metallurgy for improved life of Hot
Gas Path Components
Improved efficiency
Thermal Barrier Coatings of Blades & Vanes.
Improved major inspection intervals.
Multi Fuel Firing
Technological Options
ELECTRICAL
 Up gradation of insulation of rotating machines from
Class B to Class F.
 Up gradation of protection systems including diagnostic
tools.
 Replacement of HV , EHV circuit breakers with SF6 /
Vacuum breakers for stability and to overcome
obsolescence.
C&I
 Modernization of obsolete C&I systems with State- of-ArtTechnology.
MISCELLANEOUS
 Augmentation Of CHP
 Augmentation Of Water Treatment Plants
 Introduction of Ash Water Re-circulation System.
EXPECTED BENEFITS
Increase in generation
with improved
performance
Increase in safety,
reliability, availability and
operational flexibility
Recapturing and/ or
enhancing of unit capacity
Extension of economic
useful life by 15-20 years
at comparatively lower
capital cost
Benefit by way of
additional life
Possibility of reducing
cost of generation
R&M with Efficiency Increase
Increased power output resulting from efficiency increase is
free of fuel cost, free of operational cost and free of emissions.
Fuel consumption
Rehabilitation
per kWh
Rehabilitation
w/o efficiency
improvement
Rehabilitation
with efficiency
improvement
0
20
40
years
Mega R&M
Opting for higher steam pressure & temperatures due to the
availability of better material suited for these parameters improves
heat rate and reliability
Therefore, for old plant it may be worthwhile to consider mega R&M
schemes to bring these plants up to the contemporary state of the art
plants in terms of efficiency and availability
Typically, such mega R&M may include up-rating, re-powering,
higher process parameters resulting in enhanced efficiency,
improved operational safety, reliability, advanced diagnostics etc.
Mega R&M typically consists of replacements of major equipment /
systems of the plant at marginally higher cost & longer shutdowns of
the Units are inherent.
Plans for R&M
•The importance of R&M was recognised by the
Government of India way back in 1984 when PHASEI R&M Programme for 34 thermal power stations in
the country was launched by the Central Electricity
Authority as a Centrally Sponsored Scheme
•The Government of India has now accorded high
priority to R&M and Life Extension (LE) of old
existing power plants. The funds in the form of loan
assistance at concessional interest rates are being
provided by the Government through Power Finance
Corporation (PFC) for R&M works
LIFE EXTENSION PROGRAMME
DURING 10TH PLAN
S. No.
PARTICULARS
i)
Number of thermal power stations
32
ii)
Number of thermal units
106
iii)
Estimated Cost
Rs. 9200 crores
iv)
Total Capacity involved
10,413 MW
v)
Average PLF of the units before LE programme
49%
vi)
Anticipated PLF after completion.
75%
vii)
Anticipated additional generation/ annum
23700 MU
viii)
Capacity expected after completion of LE works
10,747 MW
R&M PROGRAMME DURING 10TH PLAN
S.No.
S.No.
PARTICULARS
i)
i)
iii)
iv)
Number of thermal power stations
Number of thermal power stations
ii)
ii)
PARTICULARS
iii)
13
Number of thermal units
Number of thermal units
Estimated Cost
Estimated Cost
13
57
57
Rs.977 crores
iv)
Total
Capacity involved
Total Capacity
involved
14270 MW
Rs.977 crores
14270 MW
11TH PLAN PROGRAMME
Sl. No.
Particulars
LEP
R&M
i)
Number of thermal power stations
18
12
ii)
Number of thermal units
34
31
iii)
Estimated Cost
Rs.6000 Crores
Rs. 751 Crores
iv)
Total capacity involved
6,000 MW
7,090 MW
Thermal Units for R&M in 10th and 11th Plan
No of units for R&M in 11th Plan
45
30
40
35
25
30
20
25
20
No of units
No of units
No of units for R&M in 10th Plan
43
15
10
5
10
5
10
4
29
15
0
110 MW and 200 & 210 MW
Below
500MW
2
0
0
110 MW and 200 & 210 MW
Below
Unit size
500MW
Unit size
Total MW for R&M in 11th Plan
Total MW for R&M in 10th Plan
360
1000
5000
8910
0
110 MW and Below
110 MW and Below
200 & 210 MW
200 & 210 MW
500MW
500MW
6090
POWER PLANT R&M OBJECTIVES
availability
improvement
efficiency upgrading
environmental
control updating
increased electrical
output
reduced fuel
consumption
emissions within
new norms
life extension
improved reliability
RESULTS
increased power
output
reduced power
generation cost
operation free
of restrictions
plus
CDM BENEFITS
Challenges in R&M
•Limited Agencies for R&M implementation
in the country.
•Prohibitive cost of New Technologies
impediment for introduction on wider scale.
•Unfavorable cost benefit analysis.
•R&M activity to be linked with planned
shut down.
CDM Potential in R&M
Offers
substantial
CDM
benefits
reduction/substitution of coal by:
through
Enhancement of efficiency by
upgrading cycle parameters
Co-firing of biomass with coal in
coal fired furnaces
R&M SCENARIO IN NTPC
•Department formed in 1995 to Cater to R&M of its
own Stations
•R&M is identified as Key Thrust Area as the many
NTPC plants are crossing 1,00,000 operating hours
•R&M of power plants of 10,799 MW capacity has been
undertaken / in progress
•R&M of power plants of 7,642 MW capacity is under
planning
•The cost of R&M may be up to Rs. 1.5 crores per MW
depending on the life and condition of the plant.
NTPC R&M Project under CDM:
NTPC has taken up Badarpur R&M project under
CDM
PIN is already prepared
NTPC’s EXPERIENCE SO FAR
NTPC Talcher TPS (4x60+ 2x110 MW)
R&M Scope
•Extensive RLA and R&M of SG and TG
•Retrofitting of existing ESP and addition of new fields
•Replacement of Static Excitation System, Power & Control cables,
replacement/ Retrofit of HT/LT Switchgear ,Augmentation of H2 plant
•Renovation of Cooling Towers
•Augmentation of Ash Handling
•New AWRS
•New Railway Siding inside the plant
•New Coal Handling Plant
•R&M of Switchyard
R&M cost - Rs 1.50 Crs/MW
PLF is around 88% as against 19% during takeover in Jun 1995.
NTPC’s EXPERIENCE SO FAR
NTPC Tanda TPS (4x110 MW)
R&M Scope
•Extensive RLA and R&M of SG and TG
• ESP Renovation
•Replacement of 6.6 KV & 11 KV Switch gear
•Replacement of LT Switch Gear
•Renovation of Fire Fighting system
•New Stacker Reclaimer
•Additional DM Stream
•New DDCMIS for Units 1&2 and Upgradation of DAS for Unit 4
•Clarification of CW Make up water system & Effluent Treatment plant
R&M cost - Rs 1.17 Crs/MW
PLF is around 85% as against 21% at the time of
takeover in Jan 2000
EXPERIENCE OF TECHNOLOGY UPGRADES
•The 60 MW boilers at Talcher TPS have been redesigned taking
into account the current coal characteristics. Milling system have
been upgraded.
•The 110 MW Units at Kothagudam have been upgraded to 120
MW by PPIL with a Turbine HR less than 2000 Kcal/Kwh.
•110 MW Unit at AECO, Sabarmati has been upgraded to 120 MW
by NASL with Turbine HR improvement of approximately 140
Kcal/Kwh.
•No. of 200/210 MW LMZ Units have been upgraded to 225 MW in
other countries with considerable improvement in Heat rate. These
are now being planned in India.
Government’s Initiatives
Partnership in Excellence
CEA has identified 26 stations which are operating at a
PLF of less than 40%. These stations would have a
“Partnership in Excellence” with better performing
utilities, so as to achieve an improvement in performance
in the shortest possible time. Subsidized funds would be
made available for this programme through PFC / REC.
The target is to achieve a PLF of 60% in two years time.
Role of NTPC
NTPC has been entrusted the responsibility of 14 stations
out of the identified 26. Site office has been opened at all
the 14 stations and experts have been posted at all sites.
The teams will aim to implement the customized O&M
systems and will carry out one cycle of overhauls.
Government’s Initiatives
R&M of SEB stations
The 10th Plan envisaged R&M of an installed capacity
of 11,055 MW with a target of achieving 75-80% PLF
and 20 years of Life Extension.
Role of NTPC
NTPC has taken up consultancy services for a few of
these stations.
NTPC initially took up four power stations for
R&M/LE (Total – 1332.5 MW).
Subsequently another six stations (1512.5 MW)
were taken up for R&M / Life Extension (LE) / Recommissioning / Residual Life Assessment (RLA)
Funds being provided by PFC / REC
APDP-R&M
Highlights of Achievement
Proj.
PLF
bef.
PLF
aft.
% imp.
in PLF
SOC
bef.
SOC
aft.
% imp. APC
in SOC bef.
APC
aft.
% imp.
in APC
CTPS
3x140
MW
23.97
72.66
203.13
28.60
0.80
97.20
22.30
11.43
48.75
DTPS
1x140
MW
36.78
65.41
77.84
5.28
1.88
64.40
12.59
9.88
21.52
GTPS
2x210
MW
45.00
84.00
93.19
3.00
0.70
76.67
12.40
10.23
17.50
International Best Practices in R&M
Internationally, R&M program are focused on leveraging
technological developments in various fields to upgrade candidate
plants & bring them at par with contemporary machines
International best practices range from one-to-one replacements
to Mega R&M
In USA and other advanced countries utilities have largely gone
for Mega R&M because of the age of their units & rapid changes in
their business environment which required them to remain
competitive and efficient
Hence, Mega R&M schemes such as up-gradation of process
parameters, improved balding in turbines, Re-powering, & even
installing machines of higher capacity on the same footprint were
adopted
Case Study of a German Power Plant
Improvement of efficiency and
environmental conditions by
retrofitting the units
This was mainly achieved due to
using low NOx burners in boiler,
redesigning of LP turbine and
cooling tower modernisation
The emission levels of the units
was reduced drastically due to use
of low NOx burners, installing
Flue Gas Desulfurification plant
and optimisation of operation of
ESP
Flue gas discharge through
cooling
towers,
automatic
concrete
cutter
for
existing
chimneys
Conclusion
Implementation of the R&M Schemes has benefited the
stations by way of
•Overcoming Technological obsolescence.
•Low cost capacity addition
•Extending the life of equipment / components.
•Complying with Statutory and Environmental Norms
•Sustaining availability and improved performance
There is huge potential in India for R&M activities because of
large number of old plants which are inefficient and running
below design capacity
R&M to be planned in advance before major deterioration or
breakdown of unit
Urgent need to enhance manufacturing capacity to handle
load of R&M / Creation of new manufacturing base