Overdrawing - grid breakdown inevitable

Submitted by VK Gupta on Tue, 31/07/2012 - 5:50am

Overdrawing made northern grid breakdown inevitable
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.NEW DELHI: The collapse of the northern grid on Monday was a breakdown waiting to happen because several states had been overdrawing power in recent months. This had led the frequency of the north-east-west grid to dip to critical levels between May 13 and May 16, an official said.

A senior official at the Northern Regional Load Dispatch Centre, which ensures smooth operation of the grid, said the situation had improved for a while after power regulator Central Electricity Regulatory Commission had on July 10 directed heads of state load dispatch centres of Uttar Pradesh, Rajasthan, Uttarakhand and Haryana to stop overdrawing from grid and make necessary arrangements for power purchase.

Insufficient rainfall and extreme weather conditions, however, increased the demand for power over the past 20 days, particularly from agricultural areas.

Energy demand soars during a deficient monsoon as farmers have to depend on water-lifting devices to irrigate farms. Estimates suggest that the demand for power has risen by over 25% in a few states so far this year, against expectations of a 10% to 15% rise. This has also pushed prices up in open markets.

Utilities prefer overdrawing from the grid since no immediate cash transfer is required, unlike in the case of purchase from market and private players, but this can lead to grid failure.

The utilities say their financial condition doesn't allow them to purchase in large quantities from open markets.

The northern grid operates in a narrow frequency band of 48.5 to 50.2 Hz. The frequency decreases when states draw electricity and increases when there is supply.

Power minister Sushilkumar Shinde said that at the time of the collapse, around 2.35 am, the grid frequency was 50.46 Hz, a few notches above normal.