UP-GRADATION AND REFURBISHMENT OF
GENERATING UNITS OF MANGLA POWER STATION

Location Mangla Dam/Power station is located on River Jhelum at about 120 Km from Islamabad.
Purpose Mangla Dam is a multipurpose Project. Primarily designed for Irrigation. The other by products are Power Generation. Fish Culture. Tourism and Navigation. 
Construction Mangla Power House was completed in four stages. The initial phase comprising of four units of 100 MW each was completed in 1967-69. The first extension of Unit No. 5&6 (2X100 MW) was completed in 1974 while second extension comprising Unit No. 7&8 (X100 MW) was completed in 1981. The project attained its maximum capacity of 1000 MW with the final extension of Unit No. 9&10 (X 100 MW) in 1993-94.
Dam Raising Mangla reservoir had initial gross capacity of 5.88 MAF, which reduced to 4.674 MAF (Year 2005 and was likely to reduce further with the passage of time due to sediment deposition. Keeping in view the capacity loss due to sedimentation and provision for raising in the original design and construction, Raising of Mangla Dam was started in 2004 and the Project was completed in 2009. The Dam height has been raised by 30 feet while maximum conservation level increased from 1202 feet to 1242 feet  corresponding to additional water storage capacity of 2.88 MAF. There will be additional energy generation of 644 GWh due to availability of more water and rise in net head of machines.
Up Gradation/ Refurbishment Scheme: There are four age groups of Mangla machines units 1~4 (40 years), units 5~6 (35 years), Units 7~8 (28 Years) & Units 9~10 (15 years). The first 6 Units with age of 30~40 year have outlived their useful lives due to which more resources and time are required for maintenance of old equipment besides less operational reliability. Some of the important aspects are:
 
  • Efficiency of Turbines has reduced from their designed values.
  • The Hydraulic/Mechanical Equipment have become unreliable due to aging.
  • Generators widning of existing Units 1~4 & 7~8 is of Class-B insulation whereas the latest class-F has higher tolerance  of temperature.
  • Control & Protection Equipment of old units have become obsolete and their spare components are not available for being out of production.
  • Dam life has enhanced after completion of the Dam Raising Project but the old generating units will not have life compatibility with the Dam.

In view of above, WAPDA planned to carry out Up-gradation & Refurbishment of the old Generating Units and Allied Equipment to ensure their optimized, reliable and sustainable operation in the Post Raised Mangla Dam Scenario.

Feasibility Study  As a first step, Feasibility study has been started to assess the present operating conditions of existing Civil Structures & Plant Machinery and to determine the most viable option, technical as well as economical, for Up-gradation / Refurbishment of the existing Units of Mangla Power Station keeping in view the aging effects on Electrical & Mechanical Equipment and to effectively utilize the improved power potential after Dam Raising.
Expected Benefits There are different options for Up-gradation of Mangla Power Station. According to preliminary studies at the time of Dam Raising, following benefits were envisages:
  • Capacity increase from 1000 MW to 1250 or 1500 MW.
  • Over and above annual energy increase of 644 GWh due to dam Raising, incremental energy of 125/300 GWh is expected.
Status of Feasibility Study Consultants
Consultancy Agreement
Date of Commencement
Studies Time/ Completion Time
Revised completion time
Consultancy Cost 		MWH (USA) -NESPAK (Pakistan) JV
27th April, 2011
2nd May, 2011
06 Months
08 Months (Dec, 2012)
Rs. 163.6 Million
Scope of Services
  • Determine Maximum Power Potential after Dam Raising.
  • Identification of Options for Optimum output.
  • Condition Assessment of Electro-Mechanical Equipment.
  • Study of Existing Control, Instrumentation & Protection Systems.
  • Condition Assessment of Concrete Structures.
  • Assessment of Power Evacuation.
  • CDM Studies of the Project with relevant details.
  • Cost Estimation and Economic/Financial Analysis.
  • Recommendation of the most viable option.
Progress

  • Mangla Refurbishment Project JV after incorporation of WAPDA'S comments submitted the Final Feasibility Study Report on 30th December, 2011.

  • Based on the results of extensive studies,  the Consultants have considered three major Scenarios including "Only Life Extension Option (1150 MW)", "Minimum Investment UP-rating Option (1310 MW)" and Maximum Investment Up-rating Option (1500MW)".

  • The Consultants have recommended Minimum Investment Option in which 1310 MW will be attained by replacing some major parts and refurbishment of remaining. The unit capacity of all the units, except 7&8 can not be up-rated beyond 115 MW.

  • The case to obtain approval by WAPDA Authority for selection of Refurbishment/Up-gradation option is under process.

  • WAPDA has also requested MRP-JV to locate the source of leakage from draft tube of unit NO. 8 as an additional assignment, for which the Consultant has requested for extension of time for about 2.5 months (i.e from January to 15th March, 2012 and the case for approval of WAPDA Authority for extension of time is in process.
Estimate Cost & Schedule The Construction Cost under this option is expected to be US$ 339.7 Million with the ten (10) years completion time. Implementation of Project is expected to start in 2013.
  Updated as on 31-03-2012