Unbundling of NEA by dffhrtcv3

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									STATUS OF TRANSMISSION LINE
AND EXPANSION PLAN IN NEPAL

          S. Rajbhandari
        Components of Power System
   Electrical power system mainly consist of three
    systems or components:
       Generating system
       Transmission system
       Distribution system
   Generating system consists of generating stations
    or power houses where stored in various forms
    (examples: water at height, heat energy in coal or
    oil or nuclear energy in the atoms of fissionable
    fuels) are converted into electrical energy.
    Components of Power System contd.
   Transmission system transmits electrical
    energy in bulk, generally from generating
    stations to the primary substations.
   Distribution system is the system from
    which electrical energy is distributed to
    various consumers such as domestic,
    commercial, industrial, non commercial etc.
     NEA Transmission System
   Grid (INPS) extends from east to west, ie.,
    Anarmani- Mahendranagar
   Major hydro stations connected to the grid.
   GSS Capacity: 1310 MVA
   132 kV line length: 2076 cct Km
   66 kV line length: 586 cct Km
NEA Transmission System
contd.
   Principal voltage of grid system is 132 kV.
   Majority of the lines constructed with
    double circuit, except for Bardghat-Hetauda
    section
   Constructed with conductor BEAR and
    DUCK except for Bardghat-Hetauda and
    Bharatpur-Pokhara
Single Line Diagram of INPS
     Single Line diagram, INPS
 I
                     Modi
                                     Trishuli
                            MMRS

                                                Lamosangu
            KGA

           Jhim
M/ nagar
                                                                Dubi Anarmani

           Lamai                     Htd
                Butwal      Bhrtpr              Chapur Dhalke Lahan


Tanakpur                                        Parwanipur            India


                                         Birgunj
Integrated Nepal Power System
(INPS) Map

               (NOT TO SCALE)
Why Transmission System Expansion ?
   To provide greater reliability and capacity
   To increase the ability to distribute
    available power to meet existing and future
    demands
   To meet NEA’s contractual obligation for
    transmission with various power producers
   To increase NEA’s ability to import/export
    power
        Transmission Development
   Before 1985:
   No systematic planning carried out.
   Transmission expansion mainly by ED, tandem of new
    HEP.
    Major transmission Projects (about 800 km)
              Trishuli – Balaju – Hetauda – Birgunj
              Sunkoshi – Patan
              Gandak – Bharatpur – Hetauda
              Devighat – Chabel
              Bardghat – Butwal - Kohalpur
              Hetauda – Dhalkebar
              Bharatpur – Pokhara
              Suichatar – KL2 - Hetauda
       Transmission Development contd.
   Period Between 1985 - 1992
   Transmission network planning started in 80s.
   NEA Act implemented for effective monopoly
   NEA Prepared and updated its corporate plan

     Long term demand forecasting



             LCGEP           TSMP   Distr. Plan
Transmission Development, 85-92
   NEA LCGEP, TSMP & DEP treated as
    national plans.
   NEA responsible for phased
    implementation Grid interconnection
    domestic or interdepartmental affair.
   Major Transmission Projects during the period
    (approx.500km) :
           Dhalkebar – Duhabi – Anarmani
           Kohalpur – Mahendranagar
           Balaju – Marshyangdi - Bharatpur
       Transmission Development after 1992
   Period after 1992:
   New Electricity Act; Hydropower Development
    Policy
   IPPs have access to generation;
   NEA the grid owner and IPPs the grid user for
    existing grid.
   Absence of national Grid code led many issues
    related to grid planning, expansion, operation,
    interconnection to remain as grey areas.
   Grid Interconnection no more interdepartmental
    issue
Transmission Development after 1992
   NEA faced four problems:
     What level of generation development to be
      considered/planned for transmission expansion?
      IPPs have license throughout country.
     Which expansion to be given priority?

     What performance standards to be adopted for
      expansion planning?
     Source of funding. Where does the money will
      come from for transmission expansion?
               Mismatched Triangle
   NEA, IPPs and Government bodies
                                  Government bodies
                                  MOWR
        NEA                       WECS
                                  DOED
        Roles and                                      IPPs
        Responsibilities as per
        NEA Act                                        Roles / responsibilities
                                                       As per Electricity Act
        Monopoly operation
                                                       Single buyer market
        Forced to single buyer      Missing

                                    Roles
                                    Responsibilities
                                    Functionalities
                                    Structures
    Transmission Development after 1992

   IPPs are awarded license wherever they apply for and
    wish to develop power projects where they have
    license for.
   IPPs expect NEA to provide evacuation/
    interconnection where they want.
   Their proposals for power evacuation include:
      either to break the existing trunk lines for
       interconnection
       or new transmission line to be constructed by
       NEA.
    Transmission Development after 1992
   NEA refuses:
      interconnection that harm grid security

      to add transmission capacity due to lack of
       funds.
   Rigid stands taken by both NEA & IPPs helped to
    create bottlenecks or congestion.
   Ultimately very little transmission expansion
    realized. Such expansions include (approx. 345
    km):
Transmission Development after 1992
       Khimti – Lamosangu – Bhaktapur ( NEA)
       Lekhnath – Kaligandaki – Butwal (NEA)

       Chilime – Trisuli (NEA)

       Pathlaiya – Parwanipur (NEA)

       Bhotekoshi – Lamosangu (Private)

       Indrawati – Paanchkhal (Private)

       Jhimruk – Lamahi (Private)
             Current Situation
   The conflicting interests created
    transmission bottlenecks.
   Transmission congestion in many sections
    of the INPS.
   NEA transmission plan focuses on meeting
    its internal demand and limited export.
   The TSMP envisages a 220 kV backbone
    for the purpose.
    INPS
 Western Area
                                     Modi
                                                   MMRS
                                Pokh
                    KGA          Lekh

                                                   MRS
             Jhim              Damau

M/ nagar


                              Bard                                 Htd
           Lamai                        Kawasoti
                     Butwal                               Bhrtpr


Tanakpur
 INPS
Central and East      Trishuli



   MRS                              Lamosangu




                                                 Dubi Anarmani

                      Htd
          Bharatpur              Chapur Dhalke Lahan


                                 Parwanipur            India


                          Birgunj
Transmission Line Reinforcement Plan
S. No.       Transmission lines                                  Proposed year   Status
         1   Birgunj Corridor 132 kV                             2006/07         abandoned
         2   Butwal Sunauli 132 kV                               2007/08         abandoned
             Thankot-Chapagaon-Bhaktapur 132 kV
         3                                                       2007/08         Under const.
         4   Khimti Dhalkebar 220 kV                             2007/08         Under const.
             Kohalpur-Lamahi-Shivpur-Butwal and Khimti
                Dhalkebar second circuit stringing
         5                                                       2007/08         Planned
                                                                                 Under const. (Het-
         6   Hetauda-Bardghat 220 kV                             2009/10            Bharatpur)
         7   Bardghat-Butwal 220 kV                              2011/12         Planned
         8   Hetauda-Thankot 220 kV                              2011/12         Planned
             Bharatpur-Hetauda 220 kV second circuit stringing
         9                                                       2011/12         Planned
Transmission Lines Planned/Proposed
for Power Evacuation

S. No.       Transmission lines                   Proposed year   Status
         1   MiddleMarsyangdi-Marsyangdi 132 kV   2006/07         Completed
         2   Kul III-Hetauda 132 kV               2008/09         abandoned
         3   Upper Modi-Modi Khola 132 kV         2009/10         Planned
         4   Madi I-Lekhnath 132 kV               2009/10         Planned
         5   Chamelia-Ataria 132 kV               2010/11         Planned
         6   Mewa -Tamor 132 kV                   2010/11         Planned
         7   Hewa-Kabeli 132 kV                   2010/11         Planned
         8   Lower Modi-Modi 132 kV               2010/11         Planned
         9   Sanjen-Chilime 132 kV                2010/11         Planned
     10      Upper Mars-Middle Mars 132 kV        2011/12         Planned
Transmission Lines Planned/Proposed
for Power Evacuation contd.
S. No.    Transmission lines              Proposed year   Status
     11   Kabeli-Duhabi 132 kV            2011/12         Planned
     12   Upper Tamakosi-Khimti 220 kV    2012/13         Planned
     13   Tamor-Kabeli 132 kV             2013/14         Planned
     14   Kankai-Duhabi 132 kV            2013/14         Planned
     15   Upper Karnali-Kohalpur 132 kV   2013/14         Planned
     16   Upper Seti-Bharatpur 220 kV     2013/14         Planned
     17   West Seti-Ataria 132 kV         2014/15         Planned
     18   Likhu-Khimti 132 kV             2017/18         Planned
     19   Rahughat-Pokhara 132 kV         2017/18         Planned
     20   Dudh Kosi-Dhalkebar 220 kV      2018/19         Planned
     21   Andhi khola-Butwal 132 kV       2020/21         Planned

     22   Lamosanghu-Singati 132 kV T/L                   Planned
                  Planning Dilemma
   For what capacity to plan the transmission
    network? Who can expand transmission when
    nobody knows what is required? For 83000 MW /
    42000 MW? Or for 3200 MW for 2025/26?
   Planning horizon?
       Operational planning of one year.
       Medium term 1 to 5 years
       Long term more than 5 years
   Where does the money come from if NEA is to
    satisfy IPPs’ demand?
   Over investment: low network utilization
         Planning Dilemma contd.
   Under investment: limit the use of renewable,
    increase congestion
   A transmission system should have ample margin
    to allow for contingencies and should deal with
    the uncertainties of long range forecasts.
   A properly designed transmission system provides
    a good distribution of power flows by avoiding
    excessive geographic concentrations of generating
    sources or transmission paths.
         Planning Dilemma contd.
   Performance standards provide the basis for
    determining whether system response to the
    contingency tests is acceptable. What limits/
    values to be adopted for these performance
    standards: thermal, voltage, relay, stability and
    short circuit.
   The maintenance is another issue. An economic
    network or maintain economy in the life cycle.
   What contingency levels to be followed? N-1, N-2
    or N-3?
         Planning Dilemma contd.
   Multiple contingency events include the loss of:
   A tower-line with three or more circuits
   All transmission lines on a common right-of-way
   Any transmission station including associated
    generation
   All generating units at a power plant
   A transmission line or transformer when another
    transmission line or transformer is out
    of service
       Development Options and Issues

   Generation and Transmission expansion case of chicken
    or egg story.
   For unhindered development of transmission network,
    Develop networks on the basis of investment, ownership
    and purpose :
      INPS owned by Central Transmission Utility (CTU)

      Commercial or merchant lines of private companies

      Cross border lines connected to INPS

      Dedicated cross border lines
    Development Options and Issues
   Issue is who will, when and how plan
    expansion, approve, implement and own it
    and operate transmission systems
    concerning above models.
   Investment for speedy growth is another
    issue.
       Government should invest in transmission.
       Economic feasibility instead of financial feasibility
           Development Options and Issues
   Shall we have a Central Transmission Utility (CTU)?
   If we have a CTU then shall we have more than one
    domestic transmission operators?
   How shall we attract private investment in transmission?
   How to fix wheeling charges: MW Miles, capacity
    booked or postage stamp
   Shall we issue transmission licenses anywhere,
    everywhere like generation licenses?
Development Options and Issues
   For what capacity shall we develop our network :
       Shall we have separate domestic and export networks?
        Or allow domestic network for sole export plants?
       What will be interface of domestic and export network,
        AC Synchronous or HVDC back to back?
       How shall we export internal surplus through domestic
        network?
          NEA as net integrator and nodal agency?

          Generators themselves? (Use of CTU network)

          Trading companies (Use of CTU network)
    Transmission System for Future
   Plan for a long horizon.
   North South River basin plans:
        Kosi Basin
        Gandak basin
        Karnali-Mahakali Basin
   Southern East West Trunk Line
   Mid Hill East West Trunk Line
   Export System
           Overall INPS Scheme
    (Courtesy: S.S. Bhat)
                            Trishuli


                            Modi      Damauli       Kathmandu    Khimti




                                        Bharatpur Hetauda                 Duhabi
    Lamki
                                   Butwal                   Dhalkebar

          Basin Transmission Plan
    (Courtesy: S.S. Bhat)




                                                         90~120 km


                                                             Mid hill
                                                              trunk
                                                               line


                                                        Southern
                                                        Trunk line

    MPP to Trunk Line : 30~40 km                    Mini Pooling Point
    SPP to SPP or MPP: 30~60 km                     Sub Pooling Point
    Mini PP to Mini PP or SPP or MPP : 20~30 km     Main Pooling Point
    We are pulling North South lines for each P/S
Thank You

								
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