Work apace on 800-kV circuit to plug southern region into national grid

South India is likely to get a boost in electricity supply as the integration of the southern grid to the national grid, scheduled for January next, will allow the region to tap into the other grids.

Work is apace on the 800-kV circuit between Raichur in Karnataka and Sholapur in Maharashtra. At present, the inter-region transfer capacity between the western and southern regions is 1,500 MW.

The new transmission lines between Karnataka and Maharashtra would push it up to 5,500 MW, boosting the power-starved southern region, the only grid that remains isolated from the rest of the nation.

In the past few months, there have been instances of the northern grid or the western region having had surplus power that, however, could not be transferred to Tamil Nadu, Andhra Pradesh and Karnataka. The reason: the southern region is not plugged into the national grid. But the situation will change as the integration work is likely to be completed by early next year. “We are hoping to make the integration happen by January 2014. We have completed the majority of the work and are hopeful that things will work according to plan,” a senior (Power Grid Corporation of India (PGCIL) official said.

At present, all regional grids, except the southern region, are synchronously interconnected and run at one frequency.

However, the southern region is linked asynchronously to the northern, eastern, north-eastern and western region grids through the high-voltage, direct current transmission system, which has a different frequency.

The synchronisation gained pace after large parts of the country suffered blackouts for almost three days from July 31 last year. The southern grid is being connected by two 765-kV lines, linking Sholapur of the western region to Raichur of the southern region.