Maharashtra sends notice to Tata Power for Mumbai power outage on Feb 27

Tata Power says the issuance of the notice by MSLDC is a part of laid out procedures during such events.

The Maharashtra government has asked Tata Power to explain the company’s Trombay power plant failing to comply with a directive to ramp up production—a shortage that stopped the city on February 27th morning.

In a notice dated March 2 the State Load Despatch Centre, the apex body which ensures integrated operation of the power system in the state, asked the company to send detailed reasons for the power outage or it will take strict action against the company as per the Electricity Act 2003. The SLDC said there was continuous over-drawal of electricity to the tune of 800-1700 MW from the central sector grid on February 22nd by Tata Power and it instructed the power system control centre to pick up hydro generation by 400 MW to control overdrawal. However, Tata Power's hydro generation did not pick up to required capacity. This resulted in a threat to the grid stability.

On February 27 at 09.30 am, the MSLDC directed to pick up hydro & Thermal generation to its full available capacity as there were system constraints as only two transmission lines remained in service after tripping of 220kV Mulund to Trombay line. “However, under this emergency situation also TPC has not followed the directives of MSLDC control room and thermal, hydro generation was not ramped up as per system requirement. In addition, 220kV Trombay-Salsette 2 tripped on overload which was not expected to happen as there are clear recommendations from the HLC committee constituted by MERC to remove overload tripping on 220kV lines. Subsequently Unit 5 and Unit 8 at Trombay tripped causing load loss to the tune of 850 MW in Mumbai Area.

Earlier, MahaTransco officials had said when the Mulund-Trombay line tripped because of technical snag and the State Load Transmission Centre asked the Tata Thermal Power and Tata Hydro-Electricity Power Company to increase their capacity around 9 am, Tata Power demanded an email to increase its capacity. “Had Tata Power increased generation with immediate effect, this situation would have been averted,” MahaTransco said in a statement. “It was a time critical delay which plunged Mumbai into darkness,” the official said.

When contacted, a Tata Power spokesperson said the issuance of the notice by MSLDC is a part of laid out procedures during such events and in no way suggests any fault on its part. ‘’We would like to reiterate that their assumptions about non-compliance with instructions are incorrect; under the new DSM (Deviation Settlement Mechanism) regime, the MSLDC has the ability to enter the additional generation required into the system any time via a mechanism called VSE (Virtual State Entity), which takes only 15 seconds to activate. The first communication from MSLDC to pick up generation occurred at 0930 Hrs, according to phone recordings available at both ends and witnessed by top authorities present at Trombay.  We responded immediately to the issue that had evolved as a result of MSETCL's grid tripping. Maharashtra State Electricity Transmission CompanyLand MSLDC should not absolve themselves from the responsibility of failing to take any preventive measures. " said a Tata Power Spokesperson.

A government official said Tata Power was importing cheaper power from the spot market to maintain its competitive position, which put additional burden on the transmission system and Trombay plant failed to enter the “islanding mode”, which ensures uninterrupted supply in Mumbai in case of any voltage fluctuations in the rest of the grid. The average cost of power production at Trombay, a coal-based power station, is Rs 6 a unit — almost double the cost of power procured from the spot market.