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The Northeast blackout of 2003 was a widespread power outage that occurred throughout parts of the Northeastern and Midwestern United States and the Canadian province of Ontario on Thursday, August 14, 2003, just after 4:10 p.m. EDT. Some power was restored by 11 p.m. Many others did not get their power back until two days later. In more remote areas it took nearly a week to restore power. 〔 At the time, it was the world's second most widespread blackout in history, after the 1999 Southern Brazil blackout. The outage, which was much more widespread than the Northeast Blackout of 1965, affected an estimated 10 million people in Ontario and 45 million people in eight U.S. states. The blackout's primary cause was a software bug in the alarm system at a control room of the FirstEnergy Corporation, located in Ohio. A lack of alarm left operators unaware of the need to re-distribute power after overloaded transmission lines hit unpruned foliage, which triggered a race condition in the control software. What would have been a manageable local blackout cascaded into massive widespread distress on the electric grid. ==Immediate impact== According to the New York Independent System Operator (NYISO) – the ISO responsible for managing the New York state power grid – a 3,500 megawatt power surge (towards Ontario) affected the transmission grid at 4:10:39 p.m. EDT. For the next 30 minutes, to 4:40 p.m. EDT, outages were reported in parts of Ohio, New York, Michigan, and New Jersey: Cleveland, Akron, Toledo, New York City, Westchester, Orange and Rockland counties, Baltimore, Rochester, Syracuse, Binghamton, Albany, Detroit, and parts of New Jersey, including the city of Newark. This was followed by outages in other areas initially unaffected, including all of New York City, portions of southern New York state, New Jersey, Vermont, Connecticut, and Toronto, as well as most of the province of Ontario. Eventually, a large, somewhat triangular area bounded by Lansing, Michigan, Sault Ste. Marie, Ontario, the shore of James Bay, Ottawa, New York, and Toledo was left without power. According to the official analysis of the blackout prepared by the US and Canadian governments, more than 508 generating units at 265 power plants shut down during the outage. In the minutes before the event, the NYISO-managed power system was carrying 28,700 MW of load. At the height of the outage, the load had dropped to 5,716 MW, a loss of 80%.〔 Essential services remained in operation in some of these areas. In others, backup generation systems failed. Telephone networks generally remained operational, but the increased demand triggered by the blackout left many circuits overloaded. Water systems in several cities lost pressure, forcing boil-water advisories to be put into effect. Cellular service was interrupted as mobile networks were overloaded with the increase in volume of calls. Major cellular providers continued to operate on standby generator power. Television and radio stations remained on the air, with the help of backup generators, although some stations were knocked off the air for periods ranging from several hours to the length of the entire blackout. It was a hot day (over 31 °C or 88 °F) in much of the affected region, and the heat played a role in the initial event that triggered the wider power outage. The high ambient temperature increased energy demand, as people across the region turned on fans and air conditioning. This caused the power lines to sag as higher currents heated the lines. In areas where power remained off after nightfall, the Milky Way and orbiting artificial satellites became visible to the naked eye in metropolitan areas where they cannot ordinarily be seen due to the effects of particulate air pollution and light pollution. Most of the Amtrak Northeast Corridor service was interrupted, as it uses electric locomotives; electrified commuter railways also shut down.〔 Via Rail in Canada was able to continue most of its service. The power outage's effects on international air transport and financial markets were widespread. The reliability of the electrical grid was called into question. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Northeast blackout of 2003」の詳細全文を読む スポンサード リンク
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