India faces a persistent shortage of electricity over the next four months as rapid demand growth from air conditioners and refrigeration loads overwhelms the available generation on the network. India’s grid reported a record load of 2,00,570 mw on July 7, 2021, at the height of last summer, according to the National Load Despatch Centre of the Power System Operation Corporation (POSOCO).

Since the middle of March this year, the grid has routinely reported maximum loads above 1,95,000 mw, including a peak of 1,99,584 mw on April 8 – less than 0.5 per cent below the record. During the evening peak, when there is no solar generation available, and supplies are even more stretched, loads have hit record levels in recent weeks. Exceptionally high loads have arrived far earlier this year, well before the most intense period of summer heat, implying the grid is in trouble. 

In a symptom of the struggle to meet demand, the grid’s frequency has faltered since mid-March, dropping persistently below target, with longer and more severe excursions below the safe operating range. Chronic under-frequency is a sign the grid cannot meet the full demand from customers and makes planned load-shedding or unplanned blackouts much more likely.

India has a frequency target of 50.00 cycles per second (Hertz), with grid controllers tasked with keeping it steady between 49.90 Hz and 50.05 Hz to maintain the network in a safe and reliable condition. Grid controls begin to disconnect some loads automatically if the frequency slows to 49.2 Hz with further load shedding at 49.0 Hz, 48.8 Hz and 48.6 Hz 

Power producers’ coal inventories remain very low, limiting their ability to run coal-fired units at full capacity to meet demand. Grid-connected generators hold coal stocks equivalent to less than nine days worth of consumption compared with 12 days at the end of April 2021 and 18 days in 2019. 

But the very low level of coal stocks at power plants at the start of the maximum annual demand period indicates power shortages are more or less inevitable over the next few months.