Summer heat may lead to power problems in California
June 6, 2013
• Attention centers in Southern California
• Drought is adding to concerns
As the Central Valley and much of California braces for its first seriously hot period of the year -- a weekend of 100-plus degree weather -- the state’s power grid could be pushed close to its limits, according to a new report Thursday from the U.S. Energy Information Agency and the North American Electric Reliability Corporation.
California's overall reserve picture has improved, but reserves may be a concern under extreme weather and adverse supply conditions this summer, says NERC’s annual “Summer Short Term Reliability Estimate.”
“Reliability in southern California, under extreme weather and adverse supply conditions, remains a concern.,” as the report puts it.
As in prior years, significant amounts of imported power are used to fortify reserve margins and preserve reliability, says the report, resulting in heavily loaded transmission lines into this area during peak conditions— particularly on the extra high-voltage transmission lines from the east. “As a result, unplanned transmission or generation outages, or extreme temperatures/demand may lead to resource constraints,” it says.
The report also points to recent problems at the 2,250 megawatt San Onofre Nuclear Generating Station in Orange County.
“SONGS,” as it’s dubbed, has seen premature wear in the steam tubes for both of the plant’s units, which have been shut down for repairs since late 2011.
“With this plant unavailable, a prolonged or extreme heat wave, or unexpected resource outages, could result in localized controlled load shedding to maintain system integrity,” the report says.
But Southern California is not the only area of concern. The state’s ongoing drought is also contributing to concern.
“From an operations perspective, the California Independent System Operator (Cal-ISO) has expressed concerns of emerging hydro generation challenges,” the NERC report says. “Seasonal preparations and nongeneration alternatives to mitigate load shed risk for multiple-contingency events are being considered.”