Bulk Power Transmission in India Issues, Challenges and Technology Options

1. Welcome… POWERGRID Bulk Power Transmission in India Issues, Challenges and Technology Options Theme Paper VK Prasher Executive Director Power Grid Corporation of India Ltd vkprasher@powergridindia.com vkprasher@yahoo.com

2. Evolution of Indian Power System Indian Power Scenario National Grid Transmission System Requirements Issues and Approach Technology Options Topics

3. Phenomenal expansion since independence Generation : 1349 MW 1,11,500 MW (in 1947) (in 2003) Grid : Local grid – at the time of independence. State Grids – emerged in 1960s. Regional Grids – in 1970s. Five Regional Grids – Northern, Western, Southern, Eastern & North-eastern National Grid – under progress. Evolution of Indian Power Grid

4. POWERGRID Thank You

5. Installed capacity - 104,500 MW Coal – 71% Hydro – 25% Nuclear & others – 4% Peak demand Peak power - 81,555 MW Energy (average) - 1430 MU/day Availability Peak power - 71,260 MW Energy (average) - 1325 MU/day Shortage Peak power - 10,300 MW (12.6%) Energy - 107 MU/day (7.5%) Present Power Supply Scenario

6. Power Sector demarcated in five regions

7. Existing Transmission System • Figs. are in ckt. km • State Central Total (POWERGRID) • HVDC 1,504 3,532 4,836 • 800 KV 400 550 950 • 400 kV 13,000 32,500 45,500 • 220/132 kV 2,06,000 9000 2,15,000 • Application of State-of-the-art technologies - HVDC bipole, • HVDC back-to-back, SVC, Series Compensation, FACTS etc. • Application of improved O&M technologies– Hotline maintenance, Emergency Restoration System, Thermovision scanning etc.

8. Talcher – Kolar HVDC bipole line Capacity – 2000 MW , Distance – 1400 kms one of the longest line - Inter-connecting Eastern to Southern region - Commissioned 9 months ahead of schedule ER-WR Synchronous Inter Connection (Through Raipur – Rourkela 400 kV D/c line) First major synchronous line inter-connecting two big regions: WR 30,000 MW and ER 15,000 MW With this link power system of 48,000 MW is running in synchronous mode. Recently Commissioned Major Links

9. Talcher-Kolar and Raipur-Rourkela

10. Capacity Addition Programme • Goal – Power on Demand by 2012 • Capacity Addition 100,000 MW in next 10 years • 2006-07 - 45,000 MW • 2011-012 - 55,000 MW • Future Power Supply Scenario

13. Growth of Cumulative capacity of Inter-regional links

14. Phase – 1 – Already completed Interconnection of Regional Grids through HVDC Back-to-Back links having cumulative capacity of 5000 MW – Already Completed Phase – 2 – Partly completed Hybrid system comprising of high capacity HVDC and HVAC lines (both 765 kV and 400 kV) Most of transmission lines would be part of associated transmission system of large sized generation project. Cumulative inter-regional capacity would be 23,000 MW Phase – 3 – to be completed by 2012 Ring of 765 kV transmission lines inter-connecting ER, WR and NR Cumulative caapcity would be 30,000 MW Plan for National Grid

15. HVDC and FACTS (After 2002) • HVDC Schemes • 2000 MW HVDC Bipole between Talcher in Eastern Region and Kolar in Southern Region – Already commissioned in 2002 • 2nd 500 MW HVDC back-to-back at Gazuwaka interconnecting Eastern Region and Southern Region – Scheduled by March, 2005 • 2500 MW HVDC Bipole between Balia and Bhiwadi in Northern Region – Scheduled in 2009-10 • FACTS Scheme • TCSC (40% fixed plus 5-15% variable) on existing Rourkela – Raipur 400 kV D/c line – Completed, testing under progress • TCSC (40% fixed plus 5-15% variable) on Purnea-Muzaffarpur and Muzaffarpur-Gorakhpur 400 kV D/c line – Scheduled for commissioning by June, 2006

16. Transmission System Requirements Low cost to consumer The transmission system should be suitable for an evolving system and allow implementation in stages It should meet system requirements regarding active and reactive power in the face of variation in load demand and following contingencies.

17. Transmission System Requirements The evolved system should have long term suitability and should not be too expensive initially or become redundant in future. It should meet Availability / Reliability requirements even when other elements in the system are out – within limits.

18. Issues and Effects ROW Constraint Uncertainty in addition of generation Bulk Power Long Distance Lines Staging & New Technologies Reactive Power Planning Stability

19. Issues and Approach Utilization of existing resources to the maximum extent upgradation of voltages replacement with high capacity / HVDC lines Operation at high temperature

20. Issues and Approach Transmission of bulk power over long distances over time Long bulk power transmission lines – 400 kV, 800 kV ac, HVDC etc. staging - Use of modular / multi-terminal HVDC systems reactive power control

21. Issues and Approach Severe Right of Way constraints Use of compact lines Upgradation of voltage rating of existing lines Re-conductoring Multicircuit lines Use of high voltage / HVDC lines Dynamic Thermal Circuit Rating

22. Issues and Approach Uncertainty in generation, Open market Matching Transmission Lines Greater change of flow – reactive power support Staging may be essential Modular constructions

23. Issues and Approach Inter area oscillations, Stability Unified Load Dispatch Systems Controlled exchange of power Steady state and dynamic reactive power support Free governor, PSS tuning

24. Technology Options FACTS TCSC SVC STATCOM UPFC

25. Technology Options HVDC systems Long distance bulk power systems Back-to-Back systems Multi-terminal schemes Voltage Source Converters Unit schemes, transformer less schemes etc. Tapping of power

26. Technology Options 800, 1100 kV ac lines High temperature conductors Dynamic shunt reactors Dynamic Thermal Circuit Rating

27. Thank you