NEW DELHI: India’s power grid is ready to deal with demand fluctuation and prevent tripping during Sunday’s 9-minute lights-out and light-a-candle call given by Prime Minister Narendra Modi to show national solidarity in the fight against coronavirus pandemic.Power minister R K Singh on Friday reviewed measures to ensure grid stability with officers from the grid operator POSOCO and PowerGrid , the central utility that has built the country’s arterial transmission network. The lights-out is expected to shed 15 GW (giga watt) demand, or less than 4% of the country’s total installed capacity.Officials involved in grid management and the country’s largest generation utility NTPC told TOI that because the lights-out is planned, preventive steps will be initiated to save the transmission or generation units from tripping. On March 24, TOI had first reported POSOCO putting in a special protocol to ensure grid stability after demand fell sharply as coronavirus pandemic and the lockdown curbed economic activities. Demand shrank by 25% last month to levels last seen in March 1, 2015.“India’s grid is technologically one of the best in the world and has the advantage of being a ‘one-nation-one-grid’ under a single controller,” the power minister had told TOI. “Eleven renewable energy management centres and static precipitators have been added to deal with intermittency of renewables. There are isolators and islanding mechanisms. Hydel projects can also be switched on quickly to manage any demand surge. Thermal plants have been given greater flexibility with a lower operational threshold of 55%,” he had said. These measures hold good for handling Sunday’s lights-out as well.Since households account for 33% of demand, there are apprehensions that consumption will slump during the 9 minutes of blackout and surge when people switch lights back on. While lights are switched off on Earth Day, industrial and commercial remains intact. So it is easier to absorb the demand loss. But people feel the impact on the grid will be more now due to little industrial and agricultural consumption, which together account for 59% of demand.Officials said together with state utilities steps will be taken to taper production from thermal plants, which provide the base load, or prepare some to switch off in the runup to the blackout. Production can be ramped up again and if need be, hydel can be brought on-stream till the thermal plants ramped up output. Since gas is also available due to lockdown-induced drop in CNG demand, gas-fired power plants can also be switched on to stabilise the grid.Industry players explained that the Indian grid could come under pressure because of 10% renewable content in the generation basket. “Thermal generation can be curtailed in the day to accommodate renewable in the day when demand falls. But you won’t have renewables in the night and it will take 6-8 hours to switch on a thermal plant,” one industry source said.The International Energy Agency last week cautioned countries over grid instability and resultant blackouts, especially in less-developed systems, as coronavirus pandemic curtails economic activities and demand for power.Industry and agriculture are the largest power consumers -- 41% and 18% respectively – in the country. Commercial establishments make up 8% of the consumption and domestic use account for 33%. This explains the sharp fall in demand as the lockdown has shuttered industrial and commercial activities. Domestic demand is expected to rise over the next fortnight or so when families staying at home switch on air-conditioners as temperature rises.