Report of Indian Institute of Public Administration ... - Ministry of Power

Ageing of Generating Units
State Reports (Vol.-III)
Study on `Impact of Restructuring of SEBs’
The installed thermal generating capacity of 6,425 MW has been de-rated to 6,396
MW. This year MAHAGENCO is preparing to submit proposals to Central Electricity
Authority (CEA) for its approval for further de-rating of some old units. About 48 per
cent of above thermal capacity is between 15-25 years old and 15 per cent is over 25
years old. Forced outage rates of these old machines are high resulting into their
reduced availability. Also with the quality of coal available, it is not possible to get
full rated output from these old machines. The consumption of oil per kWh of
generation also increases considerably.
Performance Parameters
The details of performance parameters achieved in five years preceding restructuring
and after restructuring are indicated in table below:
Particulars
Table: Technical Parameters
Years before Restructuring
10.26
Years
After
Restructuring
5 th 4 th 3 rd 2 nd 1 st 1 st 2 nd
PLF (%) 72.78 74.34 71.93 75.07 76.62 73.05 77.69
Heat rate (kcal/kWh) 2743 2804 2717 2680 2675 2688 2675
Oil consumption (ml/kWh) 2.54 2.68 2.65 2.18 1.96 2.27 2.00
Auxiliary consumption
(thermal) (%)
8.73 8.82 8.81 8.75 8.74 8.83 8.80
Availability (thermal) (%) 86.06 86.49 83.79 84.64 85.57 81.18 84.41
ABT incentive
Unscheduled breakdowns
in 1000 X MWh (rounded
off)
Total manpower employed
5847 4627 4620 4537 3619 5468 NA
Sanctioned staff: 17,436
Staff filled in: 14,001
It is seen from the above table that despite adverse conditions cited earlier, there has
been improvement in the performance. On account of shortage of capacity in the
State, units were not spared for carrying out annual overhaul and statutory overhaul
works. This also added to increased forced outage rates. As a result, availability and
Plant Load Factor (PLF), both suffered adversely. The figures for 2 nd year after
restructuring are projections.
Annual Overhaul/Capital Overhaul (AOH/COH), which used to be availed after 18/24
months of boiler operation, were progressively taken within 12/18 months of
operation. In 2005-06, AOH/COH of 20 units was completed. 29 units are scheduled