Power ‘islanding’ of Delhi ready for roll-out

“The present quantum of essential load spread across various distribution companies of Delhi is about 930 MW,” a Delhi Transco Ltd (DTL) official said.

The following stations will serve as the capital’s power sub-islands when the Northern Grid fails — Dadri-Jhajjar-Pragati with a peak load of 2,315 MW; Bawana with a peak load of 600 MW,BTPS-Pragati with a peak load of 500 MW and Rithala with a peak load of 20 MW.

Ideally,there should be only one power ‘island’ but the official said there were advantages of having four ‘sub-islands’. “In case one sub-island is hit by snag,the rest three can supply uninterrupted power to essential services,” the official said.

The July 2012 grid failure had paralysed normal life in many states and hit nearly half the country’s population. It prompted the Centre to ask states to take measures to ensure that such blackouts do not imperil essential services like the railways,Metro trains,hospitals and drinking water supply. Delhi is the only city to have submitted a plan and is ready to implement it,which was given the green signal by the Union Power Ministry on Tuesday.

Being the capital city,Delhi is home to the President’s House,Parliament House,other VVIP addresses,defence installations and hospitals that draw patients from all over the country and overseas – establishments that need uninterrupted supply of power.

The power ‘islanding’ system will work like this: It will automatically isolate Delhi’s power system from the grid when grid disturbance is imminent. A fall in frequency to 47.9 Hz will be taken as an indication that grid disturbance is imminent. After isolating the city’s power system from the grid,it will continue to meet the emergency power requirements of essential services : VVIP load,Delhi Metro,water supply,Indian Railways and hospitals,among others.

DTL officials said Delhi was now ready to roll out the ‘islanding’ system. The essential equipment for ‘islanding’ and ‘sub-islanding’ had been put in place,an official said. “The system is ready. Only minor completion works are remaining in the communication system linked with the centralised control room. But that is only the display part,the system is otherwise ready,” a DTL spokesperson said.