A look at some notable power outages around the world:
July 31, 2012: Three power grids across half of India fail in what authorities call overdrawing of the system, leaving a record 620 million people without power for several hours and raising serious concerns about whether the country's outdated infrastructure can meet soaring demands.
July 30, 2012: India's northern electricity grid fails for much of the day, leaving 370 million people without power.
Nov. 10, 2009: Storms near the Itaipu hydroelectric dam on the Paraguay-Brazil border are tentatively blamed for outages that cut power to as many as 60 million people in Brazil for two to three hours. The entire nation of Paraguay, population 7 million, is also briefly blacked out.
January-February 2008: Winter storms cause a nearly two-week blackout to about 4 million people around the central Chinese city of Chenzhou. Eleven technicians reportedly die trying to restore power.
November 2006: A German power company switches off a high voltage line over a river to let a cruise ship pass. It triggers outages for 10 million people in Germany, France, Italy and Spain.
Aug. 18, 2005: An imbalanced power grid kicks power plants offline in Indonesia leaves almost 100 million people in the dark, many for more than five hours.
July 12, 2004: Heavy use of air conditioners and other factors are blamed for blackouts affecting at least 7 million people in Greece just a month before the summer Olympic games.
Sept. 28, 2003: A short in a power line in Switzerland leads to blackouts affecting 95 percent of Italy. Some 55 million people are without power for as long as 18 hours.
Aug. 14, 2003: The worst U.S. blackout. Power line problems in the Midwest trigger a cascade of breakdowns that cut power to 50 million people in eight states and Canada, some for more than a day.
March 11, 1999: Lightning hits a power substation in Brazil's Sao Paulo state, leaving 97 million people without power for as long as five hours. An official says it is linked to transmission lines from the Itaipu dam.
March 1989: A solar geomagnetic storm knocks out power to 6 million people in the Canadian province of Quebec and parts of the U.S. for nine hours.
July 13, 1977: A lightning bolt knocks out electricity to about 8 million people in New York City. Power isn't fully restored until 25 hours later after widespread looting.
Nov. 9, 1965: The Great Blackout shakes Americans' faith in the power system. A faulty substation relay darkens New York City and thousands of square miles of the U.S. northeast for about 14 hours. Power is out for 25 million people. It inspires the popular film, "Where Were You When the Lights Went Out?"