Several years ago, I reported on energy and insulator trends in India( INMR Q2, 2008: India: Caged Tiger No More?) and now seems a good time for an update. That’ s because this past April there were two important events in Delhi: Gridtech 2013, where more than 120 domestic and international manufacturers showcased state-of-the-art equipment and technologies, including insulators; and a CIGRE Colloquium on UHV that featured participation by a range of experts.
Urgent Need to Expand India’ s Power Network
Currently, India’ s electrical network is seen as a serious threat to continued economic development since the system’ s expansion has not kept pace with recent annual GDP growth, now estimated at about 7 %. At present, the Indian power system has a capacity of about 233 GW, including private production. To match expected GDP growth, however, this must increase to about 337 GW by 2017, and then to 488 GW by 2022( with a perspective of 685 GW in 2027). These projections are seen as realistic and based on government planning, with a view to what has happened in China, a neighbor with similar population constraints. Tremendous development of the power sector is therefore expected, even if past experience with significant‘ slippages’ suggests that these targets could be difficult to achieve. Problem areas that will need to be addressed in this regard include fuel constraints, regulatory and tariff issues as well as environmental and bureaucratic delays in obtaining the required approvals and permits. An often ageing and overcrowded distribution system will only add to the overall challenge in terms of needed major refurbishment.
Hydraulic and coal resources in India( as in most places) are located far from the main energy consumption centers while corridors available for new lines are limited. This means that UHV lines( AC as well as DC) will have to be constructed to transport the additional power requirements foreseen in the plan. Moreover, another factor to be considered in the process will be that the country is presently divided into regional‘ power islands’ that will need to be interconnected using DC links.
India’ s first ± 500 kV HVDC transmission was put into operation in 1991 and runs 815 km between Rihand and Dadri. Two subsequent ± 500 kV DC lines, with a total length of more than 2000 km, were then commissioned between 2002 and 2010. The first UHVDC ± 800 kV line from Biswanath Chariyali to Agra, will have a length of 1750 km and is expected to be ready in 2014. Work has also commenced on another ± 800 kV line, covering 1400 km between Champa and Kurukshetra. Moreover, like China, India is now also exploring ± 1100 kV DC transmission.
India
China
UHV AC projects are now also underway. The need to transmit large blocks of power from distant generation sources to main load centers, while minimizing losses as well as facing limited land availability and right of way constraints, has pushed system operators to select a 1200 kV system voltage, with an operating voltage of 1150 kV against the 1000 kV selected by China. This is regarded as offering higher power transfer capability while still keeping basically the same lightning impulse and switching impulse insulation levels( and also the same clearances) through reliance on high performance multiple-column surge arresters.
Comparison of Power Capacity in China and India
Due to the innovative nature of a 1200 kV system and the unavailability of any field-proven equipment, a demonstration Project has been built in Bina, in Madhya Pradesh. The goal was to give Indian manufacturers the opportunity to qualify locally-developed equipment and components while, at the same time, learning about safety, quality and operational requirements of such a UHV system.
The Bina Demonstration Station is by any measure quite impressive, with two 1200 kV bays, single circuit and double circuit test lines as well as all the necessary station apparatus developed locally by a range of domestic manufacturers( more information on Bina can be found on p. 92).
In some respects, Bina is a model for public-private partnership. While the equipment and components have been developed indigenously at their proper full cost to the various competing suppliers, Powergrid of India has contributed by providing all the necessary testing facilities. In total, some 35 local manufacturers are presently involved in the Project, something that will also help them prepare for future national as well as international competition in the UHV sector.
In spite of all the difficulties mentioned earlier, I feel confident that energy expansion in India will continue at a fast pace and that the country will also become one of the world’ s most promising markets for insulators and electrical apparatus. At the same time, Indian manufacturers seem poised to become much stronger players on the world market thanks to the experience they are gaining through these projects and R & D activities.
40 20
YEARS
Q2 2013
Alberto Pigini pigini @ ieee. org