LAHORE - As the country is plunging deeper and deeper into energy crisis, the power generation capacity of public sector thermal power plants (Generation Companies) has been reduced to 59 per cent due to a number of factors, the most important being the aging aspect, as they are 23 to 33 years old. Scores of technical issues including their poor maintenance are also contributing in their minimal performance, which has also led to increased fuel consumption. Experts believe that a time would come in the near future that they would not remain cost-effective, meaning thereby that they would be consuming more fuel and generating less electricity. Sources said that on the average, the WAPDA's thermal plants were generating a maximum of 1, 432 MW electricity by June 2008 as compared to 3588 MW in June 2006. The break-up shows that GENCO-I, Jamshoro Power Company Limited, with the maximum load of 671 MW could only produce 445 MW till June 2008, as against its actual capacity of generating 754 MW and 472 MW till June 2007 as against the load of 837MW could produce 499 MW in June 2006. Similarly, GENCO-II, with maximum load of 1222 MW produced 700 MW in 2006 was reduced to produce 516 MW till June 2008 with the maximum load of 762 MW as against the load of 992 MW in June 2007 could able to produce 608 MW of electricity. Sources said that the output of GENCO-I has decreased with increase in ambient temperature besides restriction in the gas quota. The plant got constrains as of the boiler on Unit-1 following chocking of APHs, GRF Parts and hard deposits on the tubes. They said that by passing of high pressure heaters of Units 2,3 and 4 are the main reasons besides the chocking of air preheaters during oil firing. They said that corrosion, chocking, and leakages of steam coil air heaters during oil firing are the erratic behaviour of governing these plants. Talking about GENCO-II, the Central Power Generation Company, they said that since the commissioning of 220/132 KV Auto Transformer T-13, 132 KV Bus Bar I and II are being operated in split position. The operation of Units No 1 and 2 has become unstable due to reasons that Unit G-1 feeds Bus Bar-II with T-13 and load transmission is through L-1 and L-2 (Island). Tripping of these lines results in tripping of T-13 with heavy voltage fluctuation causing tripping of G-1. The voltage variation is affecting winding insulation of transformers generators and motors, thus badly reducing their life. Tripping of Line L-5 opens coupler breaker E5Q3, causes tripping of G-2. On instruction of NPCC to shift Unit No 1 and Unit No 2 from Bus Bar-I to Bus Bar -II and vice versa. The load on units is reduced to zero MW and therefore are desynchronised and resynchronised. They said total present generation capacity of Genco-III power plants is 1530 MW consists of TPS Muzafar Garh, SPS Faisalabad, GTPS Faisalabad, NGPS Multan and GTPS Shahdara, are not contributing upto their role in generation system de-rating with two main problems. The Turbine condenser tube have been scaling and poor performance of cooling towers. The maximum oil firing for the first time creating cold end corrosion and slag formation on boiler heating surfaces. Taking account of the chief problem, the sources said, the RCW for condenser was being treated with sulphuric acid dosing to keep PH around 7.5 so that carbonates remain dissolved and do not precipitate to form scaling. Additionally chlorine is injected to stop microbiological growth or algae. Over the years it has proved ineffective and each condenser has been cleaned with acid four times at Phase-I whereas the IPPs are using additional chemical of NALCO and neither require acid cleaning nor water jetting. The use of gas with furnace oil has its benefits like reduced furnace corrosion and erosion, reduced soot and slag formation and removal of already accumulated soot. Continuous oil firing especially at low loads resulted cold end corrosion at units 5 and 6 (RAH elements & Exp joints) corroded damper fell in IDF of Unit 4. The solution to these problems is use of fuel additives like used in IPPs. With regard to TPS Muzaffargarh, sources said that average daily gas requirement of the 130 MW plant was 200 mmcfd but SNGPL was supplying 150 mmcfd gas round the year to the power station in 2003-04 which has decreased gradually and at present only 15 mmcfd gas was being supplied by the gas company. Presently, 2 out of 6 Units were under forced shutdown due to non-availability of fuel. Maximum generation from the power station remained only 675 MW and the management was left with 9000 metric tons furnace oil stocks as of June 2008.