3.5 out of 5

http://en.wikipedia.org/wiki/Itaipu

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Nov. 11 (Bloomberg) — Power was restored in Brazil after an outage at a dam providing 20 percent of the country’s energy thrust about half of the nation’s 190 million people into darkness for at least two hours.

The 14,000-megawatt Itaipu Binacional hydroelectric dam said operations were back to normal at 6 a.m. local time after transmission failed, causing the world’s largest dam by output to forcibly shut down for the first time since it went online in 1983. The government is investigating the incident.