Did anyone foresee the risk of a midwinter electricity crisis like the one that plunged hundreds of thousands of south Floridians into darkness today?
The North American Electric Reliability Corp., the self-regulating industry group that oversees the grid, concluded in November that "the outlook for electricity reliability for the coming winter season is good" across the country, even with demand projected to increase 2 percent over last winter.
But some red flags stand out when you read NERC's winter assessment closely:
Florida has less room for error. The cushion of surplus power—that is, the available electricity in excess of what officials guessed that demand would be this winter—was smaller in Florida than in any other region of the country. The "capacity margin" for the Florida grid was 19.5 percent, which is more than the 15 percent margin that the state of Florida requires by law. But it is lower than any of the other seven regions of the country monitored by NERC. (The average of the seven regions excluding Florida was 29.7 percent.)
Uncertain weather confounds Florida predictions. "Weather volatility is the single most significant factor that will impact this year's winter peak demand" in Florida, NERC pointed out. Although the national grid operators assume that summer is peak demand time for electricity through most of North America, winter power demand in Florida has become hard to predict. "Florida has not experienced a cold winter since 2003," the NERC assessment said. The grid operators assumed that power demand this winter in Florida would be up 26 percent over last winter, because the 2006-07 winter was so unusually warm. However, temperatures were reaching record highs for February in south Florida when the power outages began cascading across the state.
Drought can choke power. In its winter assessment, NERC noted that the drought conditions throughout the southeastern United States had the potential to affect electricity—especially for generation plants that use rivers and streams for cooling water. Much of the coverage of the drought-power connection has focused on nuclear power, especially after last summer's shutdown of a unit at the Tennessee Valley Authority's Brown Ferry nuclear plant. The nuclear energy industry has tried hard to get out the none-too-comforting word that all steam-based power plants—coal, natural gas, or their own nuclear reactors—can have their operations affected by drought conditions. Florida gets 7 percent of its power from nuclear (less than the national average of 20 percent), 51 percent from natural gas, 18 percent from coal, and 22 percent from oil.
Difficulty getting power from here to there. Throughout the country, NERC has consistently for the past few years identified the lack of transmission capacity as a bigger issue than the lack of power plants. But the part of Florida that NERC highlighted as having the biggest transmission problem was fast-growing central Florida. Also, Florida does not have a strong grid connection with the rest of the country, which is why NERC considers its internal resources separately from those of the other southern states. (Texas also has little electricity interconnection with other states.) This could make it difficult to bring power from other regions of the country when needed. Nearly five years after the big power outage of August 2003 that began in Ohio and cascaded across eight states and Canada, affecting 50 million people, the calls continue to do more to update and upgrade the aging and inadequate system for moving power from place to place.
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Bypenear of AL 10:08AM December 13, 2009
ElectricPRO 3:23PM November 20, 2009
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