Energy companies say they have enough power to support the region, but demand is likely to increase as the high temperatures continue through the week.
Heat waves have a cumulative effect on the electrical grid, and an unusual aspect of this broiler is exceptionally high night temperatures. Buildings aren't cooling down, so air conditioners are forced to work harder. That puts more strain on transmission equipment, which has less chance to dissipate heat.
"The longer it lasts, the more concerned we get because it puts more strain on the system and presents more opportunity for something to go down or trip off," said Michael Milstein, spokesman for the BPA.
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