As temperatures soar to record highs across much of Southern California, state and local energy officials are asking residents and businesses to conserve power as demand for electricity surges and wildfires threaten transmission lines.
In areas hard hit by wildfires in northern San Diego County, outages are already affecting thousands of residents and visitors.
An outage triggered by the Poinsettia Fire near Carlsbad prompted the evacuation of Legoland California amusement park and neighboring Sea Life Aquarium.
Aside from the fires, the state's power grid will be strained by an increased demand for energy in typically off-peak hours, officials said.
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California Independent System Operator, a nonprofit that oversees the bulk of transmission lines and electricity market throughout the state, has asked all energy companies to postpone planned maintenance outages during the heatwave.
Operators say they will likely have enough supply to carry residents and businesses through the heat wave, but are still urging conservation.
"If it cools off, turn off the air conditioning and turn on a fan," said David Song, a spokesman for Southern California Edison. "Close the door quickly on the refrigerator, which is a big energy user, things like that."
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Officials said they don't expect power to go out, but are urging customers to conserve as a precaution.
Los Angeles Department of Water and Power spokesman Albert Rodriguez said usage in the first two days of the week-long heat wave has been higher than normal, but not nearly a record high, and the system has been faring well.
LA officials encourage customers to keep air conditioner thermostats set at 78 degrees and to close curtains and drapes.
Officials also urged people to avoid running dishwashers and other appliances before 7 p.m. and to stay cool and hydrated. They also suggested checking in on elderly neighbors who are particularly impacted by high temps.