Tata Power Company today filed an affidavit before the Maharashtra Electricity Regulatory Commission alleging grid indiscipline by BSES (to be renamed Reliance Power) after BSES' Dahanu thermal power plant shut early Tuesday morning.

The latest salvo fired by Tata Power at rival BSES represents the rising acrimony in an ongoing war of words between the two sides. The two are locked in litigation too before MERC.

Tata Power sources termed the Dahanu shut down tripping. A company spokesperson said that: "This is the 65th time in the last four years that the Dahanu unit has suddenly had to shut down. On each occasion Tata Power has increased its power supply to BSES by 250 mega watts in order to maintain electricity flow to nearly a million consumers located in the Andheri (Versova), Kandivli, Borivali, Meera Road and Bhayander suburbs of Mumbai, serviced by BSES. They would otherwise have experienced a blackout."

But a BSES spokesperson told Business Standard: "This was a maintenance shut down. Normalcy will be restored in two to three days."

He added that Tata Power supplied around 250 mw of additional power to meet BSES power shortfall.

Meanwhile, Tata Power in an affidavit filed before MERC pointed out that BSES had not complied with the recommendations of the expert committee appointed by the Central Electricity Authority in the wake of grid disturbances that occurred on May 18, 23 and 29 in 2002.

The affidavit states: "The committee recommended that BSES should maintain at least 10 per cent spinning reserve (additional power availability) on their generating units for safe islanding as Tata Power is maintaining spinning reserve in their generating units.

However, contrary to this recommendation, BSES has not been maintaining the mandated spinning reserve of at least 10 per cent at its 500 MW installed capacity at Dahanu of 50 MW.

As a consequence Tata Power is required to maintain this spinning reserve for BSES and hence Tata Power ought to be compensated by BSES for this quantum of spinning reserve maintained on their behalf."

Tata Power said in its affadavit that with the increasing power requirement in October 2003, violation of grid discipline by BSES may endanger the smooth and secure operation of the grid, especially during emergencies.

"It is clear that BSES is not maintaining grid discipline and jeopardising the security of power supply reliability for Mumbai. This situation needs to be immediately rectified and BSES needs to be directed to adhere to grid discipline," the TPC affidavit adds.