Normally it’s hot weather and a spike in air-conditioner use that cause problems along California’s electricity grid. On Thursday, it was a cold snap in much of the rest of the country.
The California Independent System Operator, a Folsom entity that operates the power grid, issued a rare winter “flex alert” urging residents statewide to conserve electricity. The voluntary alert lasted through 10 p.m.
ISO spokeswoman Stephanie McCorkle said the cold weather blanketing much of North America has diverted natural-gas supplies. That left gas-fired plants in Southern California scrambling.
Even though power plants in Northern California have enough fuel, the flex alert covered the entire state.
“We’re one big grid,” McCorkle said.
Although there’s been a boom in natural-gas supplies in recent years, the unusually cold weather has ramped up demand. Daily consumption exceeded production by 57 percent last month, according to a report in the Financial Times. The U.S. Energy Information Administration said Thursday that natural-gas inventories last week were 29 percent below year-ago levels and 22 percent below the five-year average.
Californians were urged to adjust their thermostats, turn out unnecessary lights and postpone using appliances like washers, dryers and vacuum cleaners while the alert was in effect.
A flex alert is the least serious of the warnings issued by the ISO. If a situation worsens, the ISO can declare emergencies with various consequences. In a Stage 2 emergency, for instance, large industrial customers with “interruptible” contracts are required to dial back their power consumption. In return, they get discounts.