The Centre has approved the grid-islanding scheme for Uttar Pradesh. Once implemented, Lucknow, Rae Bareli and Fatehpur would not face blackout even during a grid collapse.
Currently, such a hi-tech mechanism is in place only in Delhi in northern India.
“The Centre has approved the scheme and soon we are going to invite tenders to purchase the material required for putting the system in place,” UP Power Transmission Corporation Ltd (UPPTCL) director (operations), AK Singh told the Hindustan Times on Wednesday.
The system will ensure that the National Thermal Power Corporation Ltd’s (NTPC) 5x210 MW thermal station gets automatically isolated (islanded) from the grid as soon as the grid fails and continues to generate the electricity.
In turn, the power that will be generated by the Unchahar plant will cater to the electricity requirement of Lucknow and by default also of Rai Bareli and Fatehpur, despite the grid failure.
Transmission transformers in Sarojni Nagar and Chinhat here will remain unaffected by the grid failure and continue to supply power to a large part of the state capital, especially important places like the Raj Bhawan, Vidhan Sabha, CM residence, Annexe and many others.
“We will be able to supply power to entire Lucknow with the Sarojni Nagar and Chinhat transmission sub-stations remaining active,” Singh claimed.
Similarly, transmission sub stations in Rai Bareli and Fatehpur will also continue to draw the power from Unchahar.
The first stage of islanding is targeted at a frequency of 47.9 Hz with dedicated power load of 610 MW and if the grid frequency still continues to fall, the second stage of islanding is targeted at a frequency of 47.7 Hz with dedicated load of only 180-200 MW.
“The targeted power units of the Unchahar plant will automatically get isolated themselves from the grid as soon the frequency dips below the 47.9 Hz creating the possibility of failure of the grid and in the event of actual grid failure the targeted units will go on generating power,” Singh explained.
Significantly, the islanding will not only save these cities from the blackout, but the power available in the Unchahar plant can also be used as juice to revive the collapsed grid at the earliest.
The centre had asked the states to resort to the islanding mechanism to keep important places unaffected by the grid failure, in the wake of back-toback grid failure in July 2013.
In Uttar Pradesh, islanding scheme at the Narora Atomic Power station is already in operation. This generating station was able to successfully island itself during the grid disturbances of July 30 and July 31 last year.
At a frequency of 47.7 Hz, the bulk load is disconnected by sending tripping command to 220 kv feeders of Moradabad, Khurja and Atrauli and only the 220 Kv Simbholi feeder is kept running.