The power failure, touted to be one of the world's worst, hit 19 states across the north, the east and northeast of the country at 1.05 p.m. and was blamed on states overdrawing power from the northern and eastern grids.
On a day that over 600 million people were grappling with the electricity crises, the government moved Sushil Kumar Shinde from the power ministry to the more sensitive home ministry.
The power failure also left around 200 miners trapped in a mine in West Bengal's Burdwan district. The miners of Eastern Coalfields Ltd (ECL) were rescued after emergency power supply was arranged.
Over 300 trains were also left stranded mid journey for hours, affecting around 300,000 rail passengers.
The power was restored to a large extent at around 7.30 p.m. after more than six hours. Monday's blackout had lasted from 2.30 a.m. to late morning.
"The grid incident occurred at 1 p.m., affecting the northern, eastern and northeastern grids. The system is under restoration," said the official website of the Eastern Grid, among the systems managed by the state-run Power System Operation Corp Ltd.
The states affected on Tuesday were Jammu and Kashmir, Himachal Pradesh, Punjab, Haryana, Delhi, Rajasthan, Uttar Pradesh, Bihar, West Bengal, Odisha, Jharkhand, Sikkim, Assam, Meghalaya, Tripura, Nagaland, Manipur, Mizoram and Arunachal Pradesh.
These states account for half of India's 1.2 billion population.
Text and Images: Agencies (PTI/IANS/AP)
Image: A man prepares a meal as others sit at a roadside shop on a dark street following a power outage near a railway station in Allahabad on Tuesday.