A huge swath of northern India was without power Monday in the worst blackout in a decade. The cause of the failure of India’s northern grid has yet to be determined. An estimated 400 million people (about one-third of the population of India) in the states of Delhi, Haryana, Himachal Pradesh, Punjab, Rajasthan, Uttar Pradesh, Uttarakhand, and Jammu and Kashmir were affected. At its worst, the outage made more than 8000 megawatts of electrical capacity unavailable. As of 7 p.m. Indian local time, officials said 80 percent of the power had been restored.
As lack of electricity cut power to millions of fans and air conditioners, people suffered in the sweltering heat of the north Indian summer. Long distance trains ground to a halt; the Metro underground system in Delhi, the nation’s capital, was out of service; hospitals and IT call centers were running on backup power; and drinking water purification plants across northern India, which require hundreds of megawatts to operate, were out of service.
Problems started at 2:35 a.m. local time when the northern grid failed catastrophically somewhere near the city of Agra, home to the Taj Mahal, according to power officials in New Delhi. Local power authorities started diverting power from the eastern and western grid and from places as far away as Bhutan, but there was still a huge shortfall.
Business leaders were furious. The Confederation of Indian Industry (CII), the nation’s most influential business lobby, called for immediate reforms in the power sector.
“The increasing gap between the Demand & Supply of Electricity has been a matter for concern,” said CII director general Chandrajit Banerjee in a statement. “CII has consistently been highlighting that urgent steps need to be taken for addressing key issues ailing the power sector, such as improving the supply of coal for thermal power plants and reforming the state distribution utilities. Today’s outage is an urgent reminder for addressing these issues as a priority.”
Blackouts are a fact of life in India, which has struggled to meet demand for electricity in recent years. However, system-wide failures of the grid are relatively rare. The last major blackout of the northern grid took place on 2 January 2001, when an estimated 230 million people were affected for 16 hours. Poor and inadequate transmission equipment was blamed for the failure in 2001.
India’s Cabinet Minister for Power, Sushil Kumar Shinde, has announced an inquiry into the cause of today’s power failure. Shinde said at a news conference that the frequencies at which northern grid typically operates are between 48.5 and 50.2 hertz. At the time of the grid's collapse, the frquency was 50.46 Hz, which could have caused or contributed to the failure.
According to one electricity regulator, who spoke on condition of anonymity, the cause of the collapse was that the grid became overloaded as states drew more power than they were allotted.
According to PowerGrid Corporation of India, power was restored first to railways, airports, and other essential services by about 8 AM. The utility brought in electricity from both the eastern and western grids and ramped up hydropower and thermal generation in the north.
India has been struggling with electricity supply issues for some time. IEEE Spectrum's Harry Goldstein reported on attempts by Mumbai (part of India's western grid) to make itself blackout-proof in 2006. In 2010, contributing editor Seema Singh reported on how electricity policy was imperiling India's agricultural future.
Saswato R. Das writes about science and technology and is a spokesman for Lucent Technologies' Bell Labs in Murray Hill, N.J. His background is in physics.
