Cuts Power Supply After Outage
April 26, 2011
The Bonneville Power Administration said it will cut by 25% the power it supplies to in an attempt to avoid future power outages. The move byOre.-based comes in response to an outage Saturday that blacked out four million customers in nine states and parts of . It was the second major outage in less than two months, following a March 14, 2011 affecting 15 Western states and parts of . All three big investor-owned utilities said they are able to easily make up the deficit caused by the BPA cutback. utilities receive about 3% of their overall electric capacity through the interconnecting power line being throttled back by BPA. Meanwhile, San Francisco's Pacific Gas & Electric Co., the nation's largest utility, said it sold a record 21,450 megawatts of power Monday. The company expects to report that another big demand day occurred Tuesday because of a Northern California heat wave. As a result of ample surplus power in the though, PG&E already has contracted with other suppliers for sufficient power to meet demand, a company spokesman said. Petra Eggleston, a spokesman, said there were three contributing factors to Saturday's outage: overgrown trees due to a particularly rainy spring, coupled with sweltering weather that caused those leafier, robust trees to sag onto several power lines in the area. Further taxing the transmission system was an unrelated outage of a 600-megawatt hydroelectric plant at the McNary Dam on the at the Washington- border. When the tree-affected lines went down, their electric current shifted to other lines, overburdening those already-taxed wires and causing the blackout. typically supplies as much as 4,800 megawatts of power to ; one megawatt of capacity is enough to power 1,000 single-family homes at any particular time. On Monday, members of the reliability council responsible for guarding against blackouts in the met with government officials and utility executives in . But the one-day emergency meeting to discuss the recent outages ended without a formal statement on the cause of Saturday's outage. Instead, the group -- which included officials from BPA, the three utilities, several reliability councils, the U.S. Department of Energy and the U.S. Army Corps of Engineers -- made recommendations to ensure that similar outages won't recur, according to a BPA spokesman. BPA's decision to cut power to met one of the group's prime recommendations. Another called for the trimming or cutting of 300 to 400 trees. Finally, the group agreed that BPA should continue to increase the output of a hydroelectric plant that had been partly idled to accommodate salmon migration. BPA also agreed to undertake a comprehensive study of the voltage support system in the area.
VastPress 2011 Vastopolis
