Southern India hit hard by weak power grid

With major transmission projects pending or delayed, deficit issue exacerbates; wind power generation also majorly impacted

Lack of power transmission capacity in the southern region is creating varied problems for these states. The estimated shortage in this regard is about 4,000 megawatt (Mw). Close to 3,000 Mw of demand through long-term agreements is stuck due to lack of transfer capacity. Of this, Tamil Nadu needs 2,000 Mw and Karnataka another 1,000 Mw.

Three major transmission lines were shortlisted in 2014 to be awarded through rate-based competitive bidding in the region. These transmission corridors are expected to increase the capacity by 20,000 Mw. However, tenders have yet to be even issued.

Total demand from the southern region is 34,000 Mw and one reason for supply shortfall is weak transmission links. The Jaipur-Gajuwaka HVDC line, which supplies 500 Mw has tripped five times in the past week, with peak summer demand surging. “As the line trips, power transfer capacity is reduced, while demand keeps going up. At the same time, the high temperatures lead to tripping as well,” said a power market executive.

PULLING THE PLUG ON CAPACITY

• 34,000 Mw
  Power demand of south region (SR)
   
• 6,000 Mw
  Interstate transmission capacity in SR
   
• 3,000 Mw
  Pending long-term agreement for SR
   
• 2,000 Mw
  Pending projects with Power Grid for SR
   
• 20,000 Mw
  Pending projects yet to be awarded for SR
   
• Rs 2.5 per unit
  Average spot power price of all regions
   
• Rs 4 per unit
  Spot price in south region (SR)
   
• Rs 4.4 per unit
  Price discovered in SR on May 5

Sources: Ministry of power, Vidyut Pravah, Indian Energy Exchange

 

Transmission capacity was augmented last year to 6,000 Mw, says the government. However, the ability of the grid to handle fluctuations and increasing demand continues to be weak. The southern grid was synchronised with the National Grid in 2012 by commissioning of the Raichur-Solapur transmission corridor. In September 2015, Power Grid commissioned the Narendra (in Karnataka) to Kolhapur (in Maharashtra) transmission line, adding 600 Mw of transfer capacity to the south, which improved the situation. The region particularly awaits completion of the Wardha-Nizamabad-Hyderabad line, which would supply additional 2,500 Mw from eastern India. The earlier deadline was March 2016.

To make available affordable power in deficit states, the central government has been promoting spot power purchase. However, compared to the national average price of Rs 2.5 a unit, the spot power rate in the southern region was Rs 4.6 a unit last month. On the newly-launched Vidyut Pravah portal of the ministry of power, the spot power market displayed the price in the southern grid as Rs 4.4 a unit on Thursday, when that in the northern grid was Rs 3 a unit and in the eastern and western ones, Rs 2.21 a unit.

A major collateral damage of the lack of evacuation in southern states is on wind power developers, asked to curtail their generation by as much as 40 per cent.

“Of the 9,000 Mw of wind power produced in Tamil Nadu, around 40 per cent was asked to be backed down last year during summer, as the state’s grid could not handle the whole capacity. This has been brought down to 20 per cent as of now but we will face a similar issue in June-July,” said a senior wind-sector executive.