GENERATIONRENOVATION &
MODERNISATION
R. K. JainR. K. JainDirector (Technical)Director (Technical)
NTPC LimitedNTPC Limited
India Electricity – 2006 India Electricity – 2006 1111th th May, 2006May, 2006
INDIAN POWER SECTOR•Present Status:Present Status:
– Per capita consumption about 600 units per annumPer capita consumption about 600 units per annum– Installed Capacity 1,24,287 MW (April, 2006)Installed Capacity 1,24,287 MW (April, 2006)
•India’s Projected Growth is 7-8 % of GDP – Projected power requirement India’s Projected Growth is 7-8 % of GDP – Projected power requirement by year 2012:by year 2012:
– Per capita consumption 1000 units per annumPer capita consumption 1000 units per annum– Installed capacity over 2,00,000 MWInstalled capacity over 2,00,000 MW
•Projected power requirement by year 2032:Projected power requirement by year 2032:– Per capita consumption about 3000 units per annumPer capita consumption about 3000 units per annum– Installed capacity about 6,00,000 to 7,00,000 MWInstalled capacity about 6,00,000 to 7,00,000 MW
However government of India is targeting double digit growth rate However government of India is targeting double digit growth rate (10%) and hence projections are likely to get revised upwards. The (10%) and hence projections are likely to get revised upwards. The above necessitates :above necessitates :
• Sustainable Large Capacity Addition Program at higher Sustainable Large Capacity Addition Program at higher efficiencyefficiency
• Upgrading fleet of Old Power Stations which are inefficient and Upgrading fleet of Old Power Stations which are inefficient and have poor availabilityhave poor availability
R&M and Re-powering•India has large number of old plants which are India has large number of old plants which are inefficient and running below design capacityinefficient and running below design capacity•Operating pressure and temperature of these Operating pressure and temperature of these old plants are lower and there is no reheating old plants are lower and there is no reheating in some of the unitsin some of the units•Fuel available at present is different from Fuel available at present is different from what plant were designed forwhat plant were designed for•Some of the equipments have degradedSome of the equipments have degraded•Re-powering of these plant can quickly Re-powering of these plant can quickly increase the power generation at relatively increase the power generation at relatively lower cost to consumerlower cost to consumer•Re-powering can increase the cycle efficiency Re-powering can increase the cycle efficiency and hence reduce emission of greenhouse and hence reduce emission of greenhouse gases and pollutantsgases and pollutants
R&M and Re-powering•R&M will involve up gradation of milling system, APH, ESP, R&M will involve up gradation of milling system, APH, ESP, firing system etc and refurbishment of turbine, condenser, firing system etc and refurbishment of turbine, condenser, pressure parts, fans etc. pressure parts, fans etc. •Re-powering may involve following changes in plant design Re-powering may involve following changes in plant design ::
• Adoption of higher steam parameters Adoption of higher steam parameters • Introduction of topping cycle, old turbine may be Introduction of topping cycle, old turbine may be
retained in bottoming cycle.retained in bottoming cycle.• Bottoming turbine cycle efficiency improvement by Bottoming turbine cycle efficiency improvement by
adoption of high efficiency blade designadoption 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
Emissions3.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 & AUXILIARIESReplacement/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 TurbineInlet Air Cooling system.Online Compressor Washing SystemDry Low NOx Burners.Improved metallurgy for improved life of Hot
Gas Path Components Improved efficiencyThermal 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-Art-Technology.
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
Fuel consumptionper kWh
0 20 40 years
Rehabilitation Rehabilitationw/o efficiency improvement
Rehabilitationwith efficiency improvement
Increased power output resulting from efficiency increase isfree of fuel cost, free of operational cost and free of emissions.
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 importance of R&M was recognised by the Government of India way back in 1984 the Government of India way back in 1984 when PHASE-I R&M Programme for 34 thermal when PHASE-I R&M Programme for 34 thermal power stations in the country was launched by power stations in the country was launched by the Central Electricity Authority as a Centrally the Central Electricity Authority as a Centrally Sponsored Scheme Sponsored Scheme
•The Government of India has now accorded The Government of India has now accorded high priority to R&M and Life Extension (LE) of high priority to R&M and Life Extension (LE) of old existing power plants. The funds in the old existing power plants. The funds in the form of loan assistance at concessional form of loan assistance at concessional interest rates are being provided by the interest rates are being provided by the Government through Power Finance Government through Power Finance Corporation (PFC) for R&M worksCorporation (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
S.No. PARTICULARS
i) Number of thermal power stations 13
ii) Number of thermal units 57
iii) Estimated Cost Rs.977 crores
iv) Total Capacity involved 14270 MW
R&M PROGRAMME DURING 10TH PLAN
S.No. PARTICULARS
i) Number of thermal power stations 13
ii) Number of thermal units 57
iii) Estimated Cost Rs.977 crores
iv) Total Capacity involved 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
0
29
20
5
10
15
20
25
30
No
of u
nits
110 MW andBelow
200 & 210 MW 500MW
Unit size
No of units for R&M in 11th Plan
Total M W for R&M in 11th Plan
0
6090
1000
110 MW and Below
200 & 210 MW
500MW
4
43
10
05
1015202530354045
No
of u
nits
110 MW andBelow
200 & 210 MW 500MW
Unit size
No of units for R&M in 10th Plan
Total M W for R&M in 10th Plan
360
8910
5000110 MW and Below
200 & 210 MW
500MW
reduced fuel consumption
operation free of restrictions
POWER PLANT R&M OBJECTIVES
environmental control updating
availability improvement
RESULTS
increased power output
reduced power generation cost
efficiency upgrading
increased electrical output
emissions within new norms
life extension
improved reliability
plusCDM BENEFITS
Challenges in R&M
•Limited Agencies for R&M Limited Agencies for R&M implementation in the country.implementation in the country.
•Prohibitive cost of New Technologies Prohibitive cost of New Technologies impediment for introduction on wider impediment for introduction on wider scale.scale.
•Unfavorable cost benefit analysis.Unfavorable cost benefit analysis.
•R&M activity to be linked with R&M activity to be linked with planned shut down.planned shut down.
CDM Potential in R&M
Offers substantial CDM benefits through Offers substantial CDM benefits through reduction/substitution of coal by:reduction/substitution of coal by:
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 Department formed in 1995 to Cater to R&M of its own Stationsown Stations•R&M is identified as Key Thrust Area as the many R&M is identified as Key Thrust Area as the many NTPC plants are crossing 1,00,000 operating hoursNTPC plants are crossing 1,00,000 operating hours•R&M of power plants of 10,799 MW capacity has R&M of power plants of 10,799 MW capacity has been undertaken / in progressbeen undertaken / in progress•R&M of power plants of 7,642 MW capacity is R&M of power plants of 7,642 MW capacity is under planningunder planning•The cost of R&M may be up to Rs. 1.5 crores per The cost of R&M may be up to Rs. 1.5 crores per MW depending on the life and condition of the plant.MW depending on the life and condition of the plant.
NTPC R&M Project under CDM:NTPC R&M Project under CDM:NTPC has taken up Badarpur R&M project under CDMPIN is already prepared
NTPC’s EXPERIENCE SO FARNTPC Talcher TPS (4x60+ 2x110 MW)NTPC Talcher TPS (4x60+ 2x110 MW)R&M ScopeR&M Scope•Extensive RLA and R&M of SG and TGExtensive RLA and R&M of SG and TG•Retrofitting of existing ESP and addition of new fieldsRetrofitting of existing ESP and addition of new fields•Replacement of Static Excitation System, Power & Control cables, Replacement of Static Excitation System, Power & Control cables, replacement/ Retrofit of HT/LT Switchgear ,Augmentation of H2 plantreplacement/ Retrofit of HT/LT Switchgear ,Augmentation of H2 plant•Renovation of Cooling TowersRenovation of Cooling Towers•Augmentation of Ash HandlingAugmentation of Ash Handling•New AWRS New AWRS •New Railway Siding inside the plantNew Railway Siding inside the plant•New Coal Handling Plant New Coal Handling Plant •R&M of SwitchyardR&M of SwitchyardR&M cost - Rs 1.50 Crs/MWR&M cost - Rs 1.50 Crs/MWPLF is around 88% as against 19% during takeover in Jun PLF is around 88% as against 19% during takeover in Jun 1995.1995.
NTPC’s EXPERIENCE SO FARNTPC Tanda TPS (4x110 MW)NTPC Tanda TPS (4x110 MW)R&M ScopeR&M Scope•Extensive RLA and R&M of SG and TGExtensive RLA and R&M of SG and TG• ESP RenovationESP Renovation•Replacement of 6.6 KV & 11 KV Switch gearReplacement of 6.6 KV & 11 KV Switch gear•Replacement of LT Switch GearReplacement of LT Switch Gear•Renovation of Fire Fighting systemRenovation of Fire Fighting system•New Stacker ReclaimerNew Stacker Reclaimer•Additional DM StreamAdditional DM Stream•New DDCMIS for Units 1&2 and Upgradation of DAS for Unit 4New DDCMIS for Units 1&2 and Upgradation of DAS for Unit 4•Clarification of CW Make up water system & Effluent Treatment plant Clarification of CW Make up water system & Effluent Treatment plant
R&M cost - Rs 1.17 Crs/MWR&M cost - Rs 1.17 Crs/MWPLF is around 85% as against 21% at the time of PLF is around 85% as against 21% at the time of takeover in Jan 2000takeover in Jan 2000
EXPERIENCE OF TECHNOLOGY UPGRADES•The 60 MW boilers at Talcher TPS have been redesigned The 60 MW boilers at Talcher TPS have been redesigned taking into account the current coal characteristics. Milling taking into account the current coal characteristics. Milling system have been upgraded. system have been upgraded. •The 110 MW Units at Kothagudam have been upgraded to The 110 MW Units at Kothagudam have been upgraded to 120 MW by PPIL with a Turbine HR less than 2000 120 MW by PPIL with a Turbine HR less than 2000 Kcal/Kwh.Kcal/Kwh. •110 MW Unit at AECO, Sabarmati has been upgraded to 110 MW Unit at AECO, Sabarmati has been upgraded to 120 MW by NASL with Turbine HR improvement of 120 MW by NASL with Turbine HR improvement of approximately 140 Kcal/Kwh.approximately 140 Kcal/Kwh.
•No. of 200/210 MW LMZ Units have been upgraded to 225 No. of 200/210 MW LMZ Units have been upgraded to 225 MW in other countries with considerable improvement in MW in other countries with considerable improvement in Heat rate. These are now being planned in India.Heat rate. These are now being planned in India.
Government’s Initiatives
Partnership in Excellence 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 NTPCRole of NTPCNTPC 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 stationsR&M of SEB stationsThe 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 NTPCRole 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) / Re-commissioning / Residual Life Assessment (RLA) Funds being provided by PFC / REC
APDP-R&M
Highlights of AchievementHighlights of AchievementProj. PLF
bef.PLFaft.
% imp.in PLF
SOC bef.
SOCaft.
% imp.in SOC
APCbef.
APCaft.
% imp.in APC
CTPS3x140MW
23.97 72.66 203.13 28.60 0.80 97.20 22.30 11.43 48.75
DTPS1x140MW
36.78 65.41 77.84 5.28 1.88 64.40 12.59 9.88 21.52
GTPS2x210MW
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 Internationally, R&M program are focused on leveraging technological developments in various leveraging technological developments in various fields to upgrade candidate plants & bring them at fields to upgrade candidate plants & bring them at par with contemporary machinespar with contemporary machines
International best practices range from one-to-one International best practices range from one-to-one replacements to Mega R&Mreplacements to Mega R&M
In USA and other advanced countries utilities have In USA and other advanced countries utilities have largely gone for Mega R&M because of the age of largely gone for Mega R&M because of the age of their units & rapid changes in their business their units & rapid changes in their business environment which required them to remain environment which required them to remain competitive and efficientcompetitive and efficient
Hence, Mega R&M schemes such as up-gradation Hence, Mega R&M schemes such as up-gradation of process parameters, improved balding in of process parameters, improved balding in turbines, Re-powering, & even installing machines turbines, Re-powering, & even installing machines of higher capacity on the same footprint were of higher capacity on the same footprint were adoptedadopted
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 Implementation of the R&M Schemes has benefited the stations by way ofbenefited the stations by way of
•Overcoming Technological obsolescence.Overcoming Technological obsolescence.•Low cost capacity additionLow cost capacity addition•Extending the life of equipment / Extending the life of equipment / components.components.•Complying with Statutory and Environmental Complying with Statutory and Environmental NormsNorms•Sustaining availability and improved Sustaining availability and improved performance performance
There is huge potential in India for R&M There is huge potential in India for R&M activities because of large number of old plants activities because of large number of old plants which are inefficient and running below design which are inefficient and running below design capacitycapacityR&M to be planned in advance before major R&M to be planned in advance before major deterioration or breakdown of unitdeterioration or breakdown of unitUrgent need to enhance manufacturing Urgent need to enhance manufacturing capacity to handle load of R&M / Creation of new capacity to handle load of R&M / Creation of new manufacturing basemanufacturing base