Among the largest power transmission utilities in the world, PowerGrid Corporation, with over 1.02 lakh circuit km of transmission lines, operates nearly 90 per cent of inter-State transmission and wheels 50 per cent of the total power generated in the country, beside ensuring network availability at all times.

In a chat with Business Line , R.N. Nayak, the company’s CMD, spoke of the energy carrier’s capabilities to carry long-term power sales to destinations, while expressing his inability to handle the requirements of merchant power operators, who frequently transfer supplies to different locations. Excerpts from the interview:

Power generators say that after the grid failure last year you have re-rated your lines and lowered the carrying capacity; hence, merchant power cannot be transferred as before...

The biggest problem for merchant electricity generators today is that they have no buyers. (Merchant power projects sell electricity in the open market and do not have long-term power purchase agreements with the States or distribution utilities.)

PowerGrid had more than adequate capacity to carry all long-term power sales to destinations but was in no position to handle the requirements of merchant power operators, who keep transferring supplies to different locations frequently, more due to payment issues.

One must understand transmission lines are directional and wires need to be laid. It is unlike generation.

If one has 10-15 per cent surplus over and above the long-term commitments being routed, it can be wheeled. Beyond that, it is difficult.

The problem for merchant generators is that they are unable to spell out where they want to despatch.

A common complaint is that someone is not paying and hence the power has to be channelled elsewhere, to another purchaser. Moreover, many generators who had put up plants were sure they could make money and that there was no need to tie up supplies for 15-25 years.

They felt they could watch the market and decide. Now, it is only logical that they be prepared for the outcome.

How much of capacity addition is needed to ensure free flow of merchant power?

Power plants must first indicate where they want their supplies to head — north, south, east or west. A 360-degree system or four-five multidirectional lines cannot be built to evacuate power from a single generating point.

After last year’s grid collapse, what steps have you taken on grid monitoring?

The frequency range has been tightened between 49.70 and 50.20 hertz (cycles per second). Discussions are on to bring it between 49.9 and 50.1 and further down to 49.95 and 50.5 hertz.

Any violation of the band will ensure either islanding or load-shedding on the arterial networks, causing the variations.

Further, a grid security expert system has been formulated and is being discussed with the States. Intra-State lines are within the purview of PowerGrid, while transmission lines within each State fall in the domain of the State.

We have spoken to all stakeholders (States) on maintaining grid discipline and stressed that violation does not help anyone.

>shanker.s@thehindu.co.in