Contrary to an earlier openly-stated estimate of a demand reduction of 1,200 megawatt (MW), the lights off event on Sunday night for nine minutes (from 9 p.m. to 9.09 p.m.) saw a fall by about 2,200 MW in Tamil Nadu.
On Sunday, the evening peak was 10,579 MW, which was recorded at 6.55 p.m. By 8.45 p.m., the demand was down by around 500 MW at 10,091 MW. After 15 minutes, it declined further to 9,012 MW. At 9.10 p.m., it stood at 7,908 MW. In other words, due to the event, the power demand reduced by 2,183 MW in 25 minutes. In Chennai, the demand was down by around 350 MW.
The State Load Despatch Centre (SLDC) had actually sounded the Central authorities of the reduction of 1,500 MW, according to a document of the Power System Operation Corporation (POSOCO), which is in charge of the national load despatch centre. “We had visualised the fall in demand by a maximum of 2,300 MW, even though we did not discuss it with outsiders,” an official in the SLDC said.
Authorities at the field-level did expect an “over-enthusiastic response” on the part of certain sections of people, when the Prime Minister made a call for lights off. Instead of switching off electric lights only, a sizeable section of domestic consumers was said to have turned off most of their electric gadgets as well.
The State has about 2.12 crore domestic consumers, who are, more or less, evenly distributed. As many as 1.02 crore consumers are in rural areas of the State.
Fortunately, the Central government, on Saturday, publicly asked the State governments to ensure that street lights were kept on. This had provided a sustained load. Also, deviating from providing two-phased supply in the evening during this part of the year, the authorities had maintained three-phase power supply to agriculturists, which ensured the load of 300 MW, the official explained.
Almost an hour after the lights were back, the demand touched the 10,000-MW mark. On Monday morning (7.55 a.m.), it was 9,764 MW.
The supply position, post-lights-off, was managed by stepping up hydro generation (including pumped-storage hydro plants) to the extent of 1,000 MW and relief from the Central grid for about 900 MW, apart from gas-powered stations. Besides, as some western pockets of the State had rain on Sunday night, wind energy too, came in as an unexpected bonus to the tune of 350 MW, the official added.
