http://en.wikipedia.org/wiki/2009_B...raguay_blackout

Heavy rains and strong winds caused three transformers on a key high-voltage transmission line to short circuit, cutting the line and automatically causing the complete shutdown of the Itaipu Dam for the first time in its 25-year history.[3][4] The power cut, which Brazilian officials said affected 18 of the country's 26 states, brought chaos to cities including São Paulo, Rio de Janeiro, Belo Horizonte, Campo Grande and Vitória.[5]


強風大雨導致一個關鍵高壓電傳輸線短路,導致水電站整個關閉