Power cuts: Regulator rubbishes kite string theory
The state electricity regulator has rubbished Tata Power Company’s (TPC’s) claims that a kite string caused the tripping of a major transmission line on November 18 that led to prolonged power cuts in the city.mumbai Updated: Dec 02, 2010 02:18 IST
The state electricity regulator has rubbished Tata Power Company’s (TPC’s) claims that a kite string caused the tripping of a major transmission line on November 18 that led to prolonged power cuts in the city.
The Maharashtra Electricity Regulatory Commission (MERC), which took suo motu cognisance of the power cuts, including the one on November 21, issued directives to all power utilities in Mumbai on Wednesday. MERC rejected TPC’s claim in the same order.
“MERC feels that the matter regarding a kite string causing tripping of the 220 kV Trombay-Salsette Line 1 needs to be looked into seriously as any fine conducting /semi-conducting material like a kite string coming into the charged vicinity of the line would burn and volatile matter would evaporate instantaneously before relay action tripped the line,” said the order.
MERC pointed out that neither did the line restart automatically, nor did the line test charge after first tripping at 5.39 pm on November 18.
It said the tripping of Trombay-Salsette Line 2 could have been avoided had procedures been followed. “There was a gap of more than five minutes between the tripping of the two lines,” said the MERC.
MERC asked TPC to issue suitable operating guidelines/procedures, investigate the matter and submit a report.
MERC also questioned the decision to keep the state utility and TPC lines in Borivli open due to a planned outage of the Kalwa-Borivli line on a weekday. “The subsequent cascade tripping could have been averted,” said the directive. The state transmission utility has been asked to look into this.
MERC did not spare Reliance Infrastructure (RInfra) either. It said that RInfra’s Dahanu generation units took too long to restart after tripping on November 18.
About the power cuts on November 21, MERC said that power tripped because of the proximity of coconut trees to a live conductor. “It appears that the Mumbai [transmission and distribution] network is operating without adequate margins and requires strengthening,” said the order passed by MERC chairman VP Raja and member Vijay Sonawane.
MERC, however, said that since the problems happened because of transmission faults, consumers were not entitled to compensation.
MERC appointed a committee headed by IIT professor SA Khaparde and comprising representatives of all departments and firms concerned to review protection and relay settings and also to review and redesign the system to ensure effective islanding of Mumbai.