MERITS OF COMBINED CYCLE GAS BASED POWER PLANTS

Why Combined Cycle Gas Based Power Plants in place of Coal Based Sub-critical Thermal Plant (500/600 MW)?

§ The coal stock is diminishing fast and it is becoming increasingly difficult to arrange adequate coal for steady operation of the existing Power Plants.

§ Most of the existing old Units are designed for operation with high GCV coal which is very scarce and costly now. As a result, due to non availability of sufficient quality coal, the existing old Units are suffering from huge generation loss as well as financial loss.

§ Inadequate supply of coal from open cast/underground mines. Dearth of adequate washed coal. Supply of bad quality coal with huge ash, stone and boulders.

§ Exorbitant price rise of Indian coal. Restriction for import of coal. Shortage in supply during monsoon.

§ Limitation of transportation of coal by Railways. Shortage of empty wagons.

§ Social threat in acquisition of agricultural land for green field project. It has become practically impossible to acquire land; may it be barren or single crop.

§ Scarcity of consumptive water availability from river/lake/barrage/dam.

§ Difficulty in Fly Ash Management; there is “No Taker” of such huge quantity of Fly Ash.

§ To combat increasingly stringent environmental norms of MOEF over the years during its life.

Advantages of Combined Cycle Gas Based Power Plants

§ Carbon emissions can be drastically reduced to combat ever increasing global warming threat

§ Guaranteed high cycle efficiency in the range of 59% (+) compared to 36% for coal based sub-critical 500/600 MW capacity thermal Units

§ Land requirement is significantly less; 80 acres for 1000 MW which is 1/10th of coal based sub-critical 500/600 MW capacity thermal Units

§ Total Manpower requirement is less; Man-MW ratio at least 50% less i.e. less job opportunity

§ PLF and Availability Factor is very high; 95% and above since forced outage is minimum

§ Consumptive water requirement is 60% less; a boost in favour of water conservation

§ Project cost is 3.5 Crore per MW compared to 5.5 Crore for 500/600 MW coal based Units

§ Carbon Credit Benefit will be available if the CCPP is installed by abandoning old coal based sub-critical Plants like Bandel TPS or installed as a brown field Project at Bakreswar TPP

§ Issuance of NOC by MOEF will be easy since there is no pollution threat from CCPP

§ Gestation period is 30 months for 1000 MW; this is 18 months less compared to coal based sub-critical 500/600 MW capacity thermal Units

§ In case of ICB, number of participating global Bidders will be high which is most unlikely for sub-critical 500/600 MW coal based thermal Units.

COMPARISON OF COMBINED CYCLE GAS BASED UNIT WITH COAL BASED THERMAL UNIT (500 MW CAPACITY - SUB-CRITICAL TECHNOLOGY)

Sl. No.	PARAMETER	Natural Gas Based Unit	Coal Based Thermal Unit
1	Efficiency (η %)	59.4 (Series701 F4)	36 (500 MW Unit)
2	Unit Heat Rate	1448 Kcal/KWh	2389 Kcal/KWh
3	Plant Load Factor	95%	80%
4	Availability	96%	85%
5	Reliability	99%	90%
6	Land Requirement for 1000 MW	80 Acres	800 Acres
7	Consumptive Water Requirement for 1000 MW	1400 M3/Hour	4000 M3/Hour
8	Environment Impact	Environment Friendly	High
9	Man-MW Ratio for 1000 MW	0.1	0.5
10	Gestation Period for 1000 MW	30 Months	48 Months
11	Installation Cost/MW	3.5 Cr. INR	5.5 Cr. INR
12	Fixed Cost per KWh (B)	X	Y (Y>X)
13	Variable Cost i.e. Cost of Fuel	A	B (A>B)
14	% Escalation on Cost of Fuel	30% higher	Base

FUTURE AHEAD (12^TH PLAN) WITH GAS BASED PROJECTS

• Gas-based combined cycle power plants have a substantial share of the overall installed capacity in India till 11^th Plan (2007-12).
• A good number of gas based combined cycle plants has been envisaged by Ministry of Power for implementation across the country during 12^th Plan (2012-17) to address environmental issues.
• Nearly 40 projects are awaiting clearance from Central Electricity Authority, Ministry of Power.
• Ministry of Power is now giving equal importance to set up more and more combined cycle and super/ultra-super critical plants during 12^th Plan Period (2012-17) to address adverse environmental effects.

PREPARED BY DEBABRATA DEY ON 25 MARCH, 2012

COMPARISON – 4x600 MW (SUB-CRITICAL) VS 3x800 MW (ULTRA-SUPERCRITICAL)

COMPARISON – 4x600 MW (SUB-CRITICAL) VS 3x800 MW (ULTRA-SUPER-CRITICAL)

1. 4x600 MW Coal Based Thermal Power Project Units with Sub-Critical Technology:

1. 600 MW BTG Set of BHEL is not proven; 1^st set is yet to be commissioned. BHEL has done some flow path modification (stationary/moving blades & diaphragms) of the existing 500 MW HP Turbine and added another LP Turbine i.e. 1 HPT+1 IPT+2 LPT; an unproven change of the existing 500 MW TG Set which is yet to be tested and accepted. During FY 2007-08, an executing agency had to reject BHEL Proposal for 2x600 MW TG Sets for one of their green field project in absence of back-to-back guarantee by the OEM.

2. Project Cost is high; Cost/MW is high. Both equity and loan components will be high.

3. Cost of generation is high; Cost/kWh is high inviting higher tariff, a burden to consumers

4. Land requirement is more; at least 20% extra, inviting acquisition of more paddy land.

5. Total Man Power requirement is more; at least 20% extra, inviting jobs for more youths.

6. Two Nos. Twin Flue Chimney, each 275 M high, shall be needed for 2x(2x600 MW) Units

7. Two Unit Control Rooms, one each for 2x(2x600 MW) Units, shall be needed for Project

8. Efficiency is less; hardly 36%; Turbine Heat Rate is poor; hardly around 1935 kCal/kWh; worse by 120 kCal/kWh, a perpetual loss for the Power Company for 25 years.

9. Planned/forced outage of a 600 MW set will invite less revenue loss than 800 MW set

10. Planned/forced outage of a 600 MW set will reduce PLF less compared to 800 MW set

11. Net Sent Out is less; at least 9% less, a perpetual loss for the Company

12. Net Revenue is less; at least 9% less, a perpetual loss for the Company

13. Huge loss in Revenue for the Power Company over a period of 25 years life cycle.

14. Specific Coal Consumption (SCC) is high; at least 10% high, inviting high Variable Cost.

15. Consumptive Water requirement is high; at least 25%, inviting high Operational Cost.

16. Ash generation is more; at least 10% more, inviting acquisition of extra land for disposal

17. Emission level is high; a threat for the survival of life of our grand children in future.

18. Carbon Credit Benefit may not be available, a financial loss for the Power Company.

19. Allocation of Coal Blocks for the Project by Ministry of Coal may not be so easy.

20. Issuance of NOC by MOEF may be difficult since they are in favour of SC/USC Units.

2. 3x800 MW Coal Based Thermal Power Project Units with USC Technology:

1. 800 MW BTG Set of with Ultra-Supercritical technology is quite proven; there is a good number of OEM across the globe like BHEL, Alstom, Simens, MHI, Toshiba, Doosan etc.

2. Project Cost & Cost/MW is reasonable; both equity and loan components will be low.

3. Cost of generation is low; Cost/kWh is low inviting lower tariff, a relief for consumers.

4. Land requirement is less; at least 20% less inviting acquisition of less paddy land.

5. Total Man Power requirement is less; at least 20% less inviting less job for unemployed.

6. One No. Triple Flue Chimney, 275 M high, shall be required for 3x800 MW Units.

7. One spacious Unit Control Room shall be adequate to accommodate 3x800 MW Units.

8. Efficiency is high; around 45%; Turbine Heat Rate is better; around 1815 kCal/kWh; better by 120 kCal/kWh, a perpetual gain for the Power Company.

9. Planned/forced outage of a 800 MW set will invite more revenue loss than 600 MW set

10. Planned/forced outage of a 800 MW set will reduce PLF more compared to 600 MW set

11. Net Sent Out is more; at least 9% higher, a perpetual gain for the Company

12. Net Revenue is high; at least 9% higher, a perpetual gain for the Company

13. Huge gain in Revenue for the Power Company over a period of 25 years life cycle.

14. Specific Coal Consumption (SCC) is less; at least 10% less, inviting low Variable Cost.

15. Consumptive Water requirement is low; at least 25%, inviting low operational cost.

16. Ash generation is less; at least 10% less, inviting acquisition of less land for disposal.

17. Emission level is low; a relief for our grand children.

18. Carbon Credit Benefit will be available, a financial gain for the Power Company.

19. Allocation of Coal Blocks for the Project by Ministry of Coal will be easy.

20. Issuance of NOC by MOEF will be easy since they are in favour of SC/USC Units.

Special Note: If the 4x600 MW BTG Sets are yet to be manufactured by BHEL, then I would request Jindal Power to revisit the merits/demerits of 4x600 MW Vs 3x800 MW, as detailed above, not only for the benefit of their Power Company but also for the benefit of the Nation and next generation grand children in particular; for their survival in pollution free GLOBE.