Why undisrupted power supply is a challenge
The likelihood of a sharp fluctuation in electricity demand within a matter of hours in Punjab puts into spotlight the critical role played by power engineers in maintaining grid stability and ensuring minimal losses during transmission.
Under a spell of an intense heatwave, the state saw the power demand crossing 16,000 MW within 10 days. And as suddenly, a spell of rain led to the demand coming down to 10,000 MW.
Demand-supply dynamics
In Punjab, the monthly demand averages around 6,500 MW in peak winters and around 10,000 MW in summers. However, during the paddy season that starts in June, it touches a new high, before dropping in September.
The total thermal generation capacity in Punjab is 8,400 MW. The Bhakra Beas Management Board’s share is 1,140 MW, while the Central sector allocation is 4,128 MW.
During the paddy season, the normal power demand is in the range of 15,000 MW to 16,400 MW. While around 10,000 MW is drawn from the Northern Grid, the rest is sourced from thermal, hydro and renewable generation sources within the state.
The drawl schedule from the Northern Grid is intimated in advance and this includes Central sector availability, power purchase from outside agencies or banking arrangements.
In case of a sudden loss of load due to thunderstorms, the hydro generation is shut and thermal stations are put on half or less load. Though there is a sudden reduction of power demand, the drawl from the grid continues. However, the lesser utilisation opens the door for unscheduled interchange (UI) — which means the UI power can be drawn by any other state for free or at UI rates of the block.
The power purchase orders on short term or long term cannot be cancelled.
Responding to changes
Experts suggest that demand response programmes play a pivotal role in stabilising the power grid, whether it is during peak demand periods or an unscheduled sudden dip of load due to the change in weather conditions.
A sudden load change adversely affects the power grid and here is where the skills of engineers managing the system are put to test. For each state, there is a system operator who is in charge of maintaining the balance. “In case of a sudden loss of power, the system operator will do things best suited at that moment,” an official explains.
“The present grids, with their advanced monitoring and control capabilities, enable real-time adjustments to the power supply. On one side of the scale, you have power availability and on the other, the power demand of various categories of consumers as intimated by officials. Maintaining the balance is the work of the Punjab State Load Dispatch Centre,” explains former power engineer VK Gupta.
Why the supply is cut
Power supply remained disrupted in several pockets in both rural and urban areas of Punjab recently following rainfall for around an hour and strong winds. Some areas in Ludhiana went without power for over four hours following a thunderstorm just for a few minutes, while power corporation officials were forced to work overtime, sometimes for over 16 hours, to restore the supply.
Adverse weather, repeated thunderstorms and the shortage of field staff with over 25,000 vacant posts add to the challenge of delivering regular power supply across the state. Some areas, especially in rural zones, have been experiencing even longer outages, affecting both homes and businesses.
Even the increased power demand and technical faults have led to disruption in supply in many districts during the paddy season.
Punjab