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The National Grid project needs faster implementation
if the XI Plan target were to be met, official statistics
suggest. The cumulative inter-regional power
transfer capacity stood at 20,750 mw as of January 2011 - a
rather poor performance considering that the target is to
take this capacity to 32,650 mw by March 2012.
Statistics released by CEA indicate that during the XI Plan
period up to January 2011, India could add a total of only
6,700 mw of inter-regional transfer capacity. If the XI Plan
target of adding 18,600 mw were to be met, the remaining
period would need to add a substantial 11,900 mw in a much
shorter period of time.
The original target was to have an inter-regional power
transfer capacity of 37,150 mw by March 2012, implying an
addition of around 20,700 mw in the XI Plan period. The
grid capacity addition target was revised in the mid-term
Plan appraisal to 18,600 mw, implying a cumulative
achievement of 32,650 mw by March 2012.
The National Grid, being implemented by Central
transmission utility Power Grid Corporation of India Ltd
involves creating power transfer capacity between the five
major regions of India—east, west, north, south and
northeast. While the eastern and northeastern regions are
known to be supply centres thanks to a concentration of
thermal and hydropower plants, respectively, the others are
largely consumption centres. As of now all the regions,
except the southern grid, have been inter-connected and are
operating synchronously.
Out of the 6,700 mw of National Grid capacity added
during the XI Plan so far (up to January 2011), the
maximum has been in the East-to-North region where 2,900
mw has been added. It is also the East-to-North region
where the maximum deficiency in target attainment has
been observed. By March 2012, another 5,800 mw of
transfer capacity needs to come between this regions. New
transfer capacity in the West-to-North region was 2,100
mw, which came from the second 765kV Agra-Gwalior line
and the 400kV Kankroli-Zerda double-circuit line.
A big setback during the XI Plan period performance has
been the failure to set up power transfer capacity between the
northeast and northern region. At least 3,000 mw of capacity
was envisaged to transfer power from large upcoming
hydropower projects in the northeast to consumption centres
in north India. This was to be achieved through a 800kV
Biswanath-Chariyali transmission from Assam to Agra in
Uttar Pradesh. Though construction on this high-voltage
corridor has begun, its completion is unlikely by March 2012.
This line will also help import power from Bhutan where
India is pursuing a number of large hydropower schemes.
The genesis of the National Grid can be traced to a set of
inter-regional links that were developed under Central
assistance to facilitate limited exchange of operational
surplus amongst various regions. Accordingly, around 12
circuit lines (four double-circuit and four single-circuit) at
132/110kV level were developed for inter-regional
transfer. They are still operated in radial mode from time
to time. The radial mode—as opposed to the synchronous
mode—was necessary as regional grids operated
independently and at different operational frequencies.
In 1992, the eastern and the northeastern were connected
by the 220kV Birpara-Salakati double-circuit
transmission line, and are operating in synchronization
since then.
India's total inter-regional capacity stood at 5,750 mw in
March 2002 (end of IX Plan period). During the X Plan
period (2002-07), around 8,300 mw was added taking the
cumulative capacity to 14,050 mw as of March 2007.
Unconfirmed reports put the National Grid capacity at
23,800 mw, as of June 30, 2011.
Most of the inter-regional transfer involves export of
power to the northern grid. In the first quarter of 2011-12,
the northern grid imported 2,039 million kwh of power
from the other grids. This accounted for 72 per cent of the
total national grid exchange. The eastern region exported
1,441 million kwh to other grids, with exports worth 1,030
million kwh taking place to the northern grid alone.
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