India has suffered its worst blackout in over ten years following a grid failure that left more than 300m people without power in New Delhi and much of the north of the country.

The country’s northern grid crashed around 0230 this morning, with some media reports speculating that the grid failure was caused by over-drawing by states as they try to satisfy the high power demand of their citizens as temperatures soared.

Power minister Sushil Kumar Shinde initially said he was unsure of exactly what had caused the collapse but had established a committee to investigate it. However, he was subsequently reported by Reuters to blame the outage on an incident near Agra, although no details were given.

According to Reuters, the outage forced the shutdown of hydroelectric plants in the Himalayan state of Himachal Pradesh, as well as thermal power stations in Punjab and Haryana.

Authorities made restoring services to hospitals and transport systems a priority, and by midday electricity had returned to most of Delhi and the state of Uttar Pradesh. The states of Rajasthan, Punjab, Jammu and Kashmir were also hit.

“When the northern grid failed, we started taking power from the eastern and western grids,” Shinde told reporters. He also confirmed they were bringing in “an additional 8000 MW of hydropower”, including from Bhutan, to meet demand.

India current peak power deficit is around 12 per cent, but this has been made worse more recently by a weak monsoon season.

With New Delhi having recently scaled back on a target to pump $1trn into infrastructure over the next five years because of a slow down in India’s economy’s growth, such significant blackouts may become more common place.

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