Public Notice : Notice issued under section 64(2) of the Electricity Act 2003
2008-09

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3. Generation Performance and Projection

3.1 Generation Performance

The Petitioner has existing generation facility of 420 MW (2x210 MW) coal based thermal power plant at Bokaro and is also envisaging a plan for extension of another three units (Stage II) of 210 MW each.

Table 1 provides the performance of the generating units during the period 2005-2009.

Table 7: Generation Performance Actual (MU)

Year	Generation (MUs)		Total	Station PLF (%)	Auxiliary Consumption (%)
Year	Unit –I	Unit-II	Total	Station PLF (%)	Auxiliary Consumption (%)
2005-06	1240	289	1529	41.56	14.23
2006-07	1412	1303	2715	73.80	12.04
2007-08	226	1569	1795	48.86	9.95
2008-09	826	1397	2223	60.43	8.37

3.2 Plant Load Factor (PLF)

Historically the generating units have been operating at much below their potential because of transmission constraints like frequent tripping of transmission lines. In addition JSEB has not been a position to consume the power generated when both the units operate and the station is asked to back down. Apart from this there are unit outages due to tube leakages etc. Due to the above reasons the station has recorded lower PLF.

Efforts have been and are being made to remove the constraints and improve the performance of the station. Efforts are also being made to sell the surplus power to others instead of backing down the units whenever JSEB does not require the power, especially, when both the units are being dispatched simultaneously. The PLF has increased to 73.8% in 2006-07 from the mid-30% levels during the years 2000-01 to 2004-05. This can be attributed to both the units being able to operate simultaneously. However, on 31.05.2007 Unit I of TTPS has suffered a major breakdown due to sudden load throw-off to 34 MW which resulted in severe damage of all the moving and guide blades of the LP turbines. BHEL has provided its observation on the LP turbine following the blade failure and has recommended appropriate maintenance and replacement operations to be conducted (Annexure 2). Unit I was therefore not available during FY 2007-08 since major overhauling and operation and maintenance was undertaken and therefore a lower PLF was registered for FY 2007-08. For FY 2008-09, both the units were available and hence a higher PLF of 60.43% was registered. The PLF was lower than normative value due to transmission constraints, for which TVNL plans to invest in the year 2009-10. The PLF and Generation for the FY 2007-08 and FY 2008-09 are given below in Table 8:

Table 8: Projected Generation Performance for 2007-08 and 2008- 09

Year	Generation (MUs)	PLF (%)
2007-08	1795	48.86%
2008-09	2223	60.43%

3.3 Auxiliary Consumption

The auxiliary consumption is specific to a particular power station and depends on its configuration, age and related technical parameters. Auxiliary power is required for different equipments like feed pumps, cooling water pumps, air fans, coal grinding mills, ash handling equipments, common auxiliaries etc. of the generating station. The Petitioner has taken many steps to keep the auxiliary consumption of its units at minimum level like testing and calibrating defective meters measuring auxiliary consumption and installing digital energy meter in the Petitioner’s colony substation. As a result the auxiliary consumption has gone down to 8.37% in FY 2008-09 from 9.95% in FY 2007-08.

Table 9: Auxiliary Consumption for 2007-08 and 2008-09

Year	Auxiliary Consumption (%)
2007-08	9.95
2008-09	8.37

3.4 Heat Rate

The actual heat rate for the generating plant has been 2945 kCal/kWh for the FY 2007-08, though Commission had approved a normative rate of 2500 Kcal/kWh. In the year 2008-09, the actual heat rate was 3075 Kcal/kWh. The all-India weighted average heat rate for plants as per the Central Electricity Authority’s (CEA) Review of Performance of Thermal Power Stations (2007-08) has been 2703 kCal/kWh and as complete report for the year 2007-08 is still not available average rate for Eastern region is not available. For the FY 2006-07 the Eastern region average was 3148 kCal/kWh when national average was 2861 kCal/kWh. TVNL in the year 2006-07 registered a PLF of 2821 kCal/kWh which was below the Eastern average reflecting the improved performance.

Table 10: Heat Rate for 2008-09

Year	Heat Rate (kCal/kWh)
2008-09	3075

3.5 Specific Coal Consumption

The Petitioner sources D grade coal from the collieries of Central Coal Fields Limited with calorific value of about 4300 kCal/kg.

Table 11: Specific Coal Consumption

Year
Year	Specific Coal Consumption (kg/kWh)
2000-01	0.705
2001-02	0.706
2002-03	0.695
2003-04	0.680
2004-05	0.685
2005-06	0.688
2006-07	0.656
2007-08	0.689
2008-09	0.715

The all-India average specific consumption of coal as per CEA’s Review of Performance of Thermal Power Stations (2007-08) the all India for 2007-08 was 0.689 kg/kWh However, the Honourable Commission approved only a normative specific consumption of coal 0.581kg/kWh which is far off from the realistic specific coal consumption observed in the country. For the 2008-09, specific coal consumption is on the higher side. The Petitioner requests the Honourable Commission to consider the actual specific coal consumption observed by the Petitioner in its generation plant.

Table 12: Specific Coal Consumption for FY’09

Year	Specific Coal Consumption (%)
2008-09	0.715

3.6 Secondary Fuel Consumption

Due to the large number of outages experienced by the station due to transmission line trippings etc., the Petitioner has not been able to achieve the norm of 2 ml/kWh fixed by the Honourable Commission for specific oil consumption. The Petitioner observed a specific oil consumption of 2.78 ml/kWh during FY 2008-09 The following Table 7 below provides the trend in specific oil consumption over the last 7 years.

Table 13: Specific Oil Consumption

Year	Specific Oil Consumption (ml/kWh)
2004-05	2.33
2005-06	3.39
2006-07	2.31
2007-08	1.95
2008-09	2.78

The delivered cost of oil at the thermal station by the oil companies has also increased to Rs. 39045/kl in FY 2008-09

Table 14: Actual Specific Oil Consumption for 2008-09

Year	Specific Coal Consumption (%)
2008-09	2.78

3.7 Summary

The Petitioner has registered the following for the FY 2008-09:

Table 15: Generation Parameters for 2008-09

Year	Generation (MU)	PLF (%)	Auxiliary Consumption (%)	Heat Rate (kCal/kWh)	Specific Coal Consumption (kCal/kg)	Specific Oil Consumption (kCal/kg)
2008-09	2223	60.43%	8.37	3075	0.715	2.78