Gridtech 2011 started with a strong note where Mr. I.S. Jha, Director Projects, Power Grid presented the paper covering Indian power system an overview, little bit of Future transmission plan, Cross country interconnection, Issues and challenges.
Giving the overview of the power sector he said “Our installed capacity is 173,000MW and we are meeting the demand upto 120,000 MW. Our per capita consumption is coming up to 800 KW hours which conveys us that this is the opportunity for the country to add more power as the country has reached only 1/3 of the world per capita consumption. This one figure of power per capita consumption indicates that power in India has to grow. Besides if we want to maintain the growth rate of 8-9% the power sector has to grow higher than this. By the end of 2013 there will be one grid one nation.”
Giving the outline of the structure of the transmission network of the nation he said “Basically the back bone of the grid is 400 KV transmission line constituting most of the 400 kV grid and it is also supplemented by few HVDC lines like 745 kV and now we are overlaying the 765kV lines. Then we have 6 capacitors to enhance the dynamic stability. With this way we can say this is the transmission grid which can be compared with any grid in any part of the world. All the latest technology is already under operation in India for last so many years. Our regions are interconnected with the total internal capacity of 22,400 MW. In the Grid management hierarchy we have 31 state load centers ensuring the proper integration between them. We are the having state of the art technology which is centralized in 5 regions, which is seen as 1 National Grid.”
Moving towards the transmission system growth drivers he said “Strong GDP growth requires massive expansion of the power sector. This is the reason we added 22,000 MW in the 10th plan. In the 11th plan we have added 60000 MW and in the 12th plan we are targeting 100000 MW. So, transmission has to be there, where generation is.”
Second part is why generation is required and answer to this is that there is an uneven distribution of energy like coal is located in the Jharkhand, Orissa areas while the hydro is on the north region and other resources is in the coastal regions like Tamil Nadu, Gujarat, Andhra Pradesh which means we have to bring the power over a long distance and this is the reason why we need higher and higher transmission systems. Today, we are 172 GW and in next 15 years the demand will go upto 600 GW. The third phenomenon that is coming up is the change in generation of profile. Earlier in 11th plan it was 47% central sector, 34% state sector and 19% private sector. Now this proportion has been changed in the 12th plan 28% central sector (28,600 MW), 15% state sector (14,400 MW), and 57% private sector (57,000 MW). The private sector has emerged as a leading power generator in the 12th plan.
Some considerations were also presented for the future transmission planning such as increased role of ISTS power transfer, need of distance transfer system, minimum use of land and right of way, optimal cost per MW transmission, optimal transmission losses, adequate margins to cater trading, contingencies etc., implementation of proper equipment availability and manpower.
Taking people through the stages of technology that Power Grid has adopted or will adopt in future he said “India is growing at a very fast pace and so we are. Today we have 400 kV high voltage lines now we have adopted 765kV and in the next 2-3 years we are going for 1200 kV. On HVDC side we are moving from ± 500kV to ± 800 kV. This is a new technology in the world, China has just commissioned it and we are also under construction. We are also taking up the up-gradation work on the same infrastructure and hardware by installing the high capacity conductors which doubles the transmission capacity. Multi circuit towers and GIS substations are also making their way in the system. In the next 4 years 77,000 GW-km is added under the central sector while the private sector transmission is additional. Out of this major contribution is coming from 765kV i.e. 37,000 GW-km and from HVDC ± 800kV 27,000 GW-km is going to be added. Today Power Grid has the total 90,000 MVA capacity and in another 5-6 years we will add more than 100,000 MVA. The total project outlay of Power Grid for the next 5-6 years is estimated to be USD 26 Billion (Rs. 120,000 crores). This comprise of creation of 11 high capacity transmission corridors for 55 IPPs (55,000 MW) worth Rs. 55,000 crores (USD 14 billion), ultra transmission system for 6 UMPPs (24,000 MW) worth Rs. 29,000 crores (USD 6 billion), transmission system for DVC generation projects (5,000 MW) worth Rs. 11,000 crores (USD 2.5 billion), transmission system for evacuation of power from NER & Bhutan worth Rs. 11,000 crores (USD 2.5 billion). The 1200kV line which is the highest voltage line in the world are being developed and will be in action in another 2-3 years.
Showcasing the cross country interconnections scenario he said “we have already established the 3 interconnections with Bhutan now we are planning the other interconnection with Bangladesh, Nepal and Sri Lanka which is an undersea interconnection.
Lastly he elaborated on the Issues & Challenges “First is the availability of the right of way because forest & agriculture department resist the going of transmission lines through their land. This has to be tackled through right compensation and technology. Secondly, our expansion is multi fold and we are going from 173GW to 600GW in the next 15 years. So, we cannot sustain the demand with 765kV line, we have to look for newer and better technologies. Thirdly, cable manufacture should develop new and improved cables which can transfer more power as 70% of the power is transferred through overhead cables. The cables should also be cost effective. One area where we haven’t had any focus is the development of indigenous machines. From the last 20 years we are operating on HVDC but we don’t have to capacity to the manufacture HVDC here. For this we have taken out the tenders for the companies to come up and establish the units here in India because when equipments are here, demand is here, why not a factory should be here.