Souths power woes to continue despite new link

Written by Anil Sasi | New Delhi | Updated: Aug 17 2014, 17:10pm hrs
Power GridRaichur circuit: Ancillary transmission lines nowhere near completion
Even as Prime Minister Narendra Modi on Saturday dedicated to the nation the RaichurSolapur 765kV second circuit line, the key grid link between the southern region and the rest of the country is nowhere close to alleviating the woes of the power-starved south.

Despite a rated capacity for wheeling 2,100 MW of power flows, transmission constraints would continue to bottle up power flows to the southern region from the rest of the country as a dozen associated transmission lines on either sides of Raichur and Solapur are badly delayed.

After factoring in for contingencies, the net benefit in terms of incremental flows to the south on account of the new line is just around 350 MW, as per the website of the national grid manager POSOCO.

In effect, the relief to the south in terms of simultaneous import capacity (or power flows at the same time) is likely to be restricted to 350 MW, enabling the import capability of the southern region to go up to about 4,000 MW from the estimate of 3,650 MW prior to the commissioning of this new line, government officials involved in the exercise said.

The new line that was commissioned on June 21 this year will wheel power to the southern region alongside a parallel line with a similar capacity that was commissioned earlier on December 31, 2013. Despite the two Raichur-Solapur lines going on stream, one link would have to be kept as a buffer under the single contingency (N-1) rule, which covers the possibility of the loss of any single transmission line at any time. An official involved in the exercise said that apart from the fact that the capacity of 2,100 MW of the single line, on paper, is rendered redundant on account of the associated lines not coming though, there is the additional problem of setting aside the reliability margin for an event such as the tripping of the 2,000 MWe (mega watt electrical) Kudankulam atomic station. A margin of at least 750 MW is to be set aside for this, leaving only a free transfer capacity of about 350 MW and giving the southern region an effective relief of just that much. A Power Grid Corporation (PGCIL) official stated for the record that work on the other lines is being expedited.

Among the lines that should have come up simultaneously, but are hanging fire include a crucial 6,000MW HVDC line from Raigarh, Chhattisgarh to Pugalur, Tamil Nadu, a line that has been under discussion between the Central Electricity Authority and state-owned transmission utility PGCIL for the last one year but where action on the ground is yet to be initiated.

Added to this, are delays in associated lines and substation infrastructure that are under construction for sending additional power to south, including those from the western region: the RaipurWardha 765 kV double circuit (D/C) line, WardhaAurangabad 765 kV D/C line, Solapur-Pune 765 kV (single circuit) S/C line and the Pune and Aurangabad 765kV sub stations.

In the southern region, those facing delays include GootyMadhugiri 400 kV D/C line, MadhugiriYelhanka 400 kV D/C line, RaichurKurnool 765 kV S/C line, KurnoolThiruvalam 765 kV D/C line, Thiruvalam 765/400 kV substation, VijayawadaNellore 400 kV D/C line, ThiruvalamSholinganallur 400kV D/C line.

There are delays in additional planned lines, including the 765 kV D/C WardhaHyderabad (via Nizamabad) line that was planned nearly three years ago. The clearance for the 350 km line is pending with the power ministry that has to approve it under Section 68 of the Electricity Act (right of way for overhead lines).

The 765 kV D/C WaroraWarangal line spanning 260 km is yet to be approved by a planning committee while the 6,000 MW HVDC line between Raigarh and Pugalur is stuck in the planning stage for the last one year. The south is faced with a continuing power crisis.

While Indias overall peaking shortage defined as shortfall in generation capacity during the time when the electricity consumption is at the maximum has come down, the shortage in the south is increasing and is headed for the worst situation in five years.