Indraprastha Power Station
The present available capacity of this Station is 247.5 MW. Since it is a coal based station, Deshaled coal having ash contents less then 34% is being procured from NCL, Bina. New ESPs have been commissioned recently on all the units at a total cost of Rs.35 crores approx. to restrict the particulate emission below 50mg/NM3.
All these units are quite old and need major R&M to remain in operating condition for which certain schemes have been prepared.
Rajghat Power Station
Two Units of 67.5 MW were installed in 1989-90 at Rajghat Power House as Replacement of old Units and the present generation capacity of this Station is 135 MW.
The Units of Rajghat Power House had inherent problems of high vibration and axial shift persisting for last several years leading to low PLF and low reliability of these machines. Even after overhauling through OEM the problem used to reoccur after the operation of Units for about 5 – 6 months. Another cause of low PLF and PAF was frequent boiler tube leakages and loss of flame.
During the last overhauling of unit No.2 the problem was analyzed and found that it was due to skewed expansion of the turbine casing caused by jamming of guide keys. The gradient of turbine sole plate was also down from rear pedestal towards the front pedestal. The condenser neck was cut and turbine was re-floated after matching the sole plates, parting plane and vertical joint of turbine. The unit is now operating at around 85% PLF.
Similar rectification works are taken up in unit no. 1 also in the ongoing overhauling since 19th April 06.There after RPH is expected to perform at around 80% PLF.
Gas Turbine Power Station
Six Gas Turbine Units of 30 MW each were commissioned in 1985-86 to meet the electricity demand in peak hours and were operating on liquid fuel. In 1990 the Gas Turbines were converted to operate on natural gas. Later due to growing power demand the station was converted into combined cycle gas turbine Power Station by commissioning 3x34 MW Waste Heat Recovery Units, in 1995-96. The total capacity of this Station is 282 MW. The gas supply has been tied up with GAIL through HBJ Pipeline. The APM gas allocation was not sufficient for maximum generation from the power station. Subsequently with the availability of Regassified -LNG an agreement was made with GAIL in Jan. 2004 for supply of R-LNG so that optimum generation could be achieved. The performance of the station has improved from 49 % in 2002-03 to 70.76 % in 2005-06.