No problem on the state’s power grid as eclipse sends solar generation plummeting.
FOLSOM, Sacramento County — Monday’s partial eclipse statewide took a sharp, sudden bite out of solar power production in California.
And the electricity grid survived just fine.
Shortly after 9 a.m., the state’s fast-multiplying solar farms were plunged into semidarkness, just when they would normally be revving up.
At the control center for California’s electricity grid in Folsom, display screens showed solar generation plummeting as the eclipse neared its midmorning peak. Electricity from hydroelectric dams and natural gas power plants surged to pick up the slack.
Then, as the sunlight returned, solar power rebounded even more quickly than it dropped, while hydropower tailed off.
“If there’s any doubt about how planning pays off, we demonstrated it this morning,” said Eric Schmitt, vice president of operations for the California Independent System Operator. “We didn’t have any major challenges on the system, even minor challenges. We’re very pleased with how smoothly it went.”
Monday’s event turned into a test for how well an electricity system increasingly reliant on renewable resources can handle an eclipse. California
uses far more solar electricity than any other state. Enough large solar facilities have been installed so far to produce — at maximum — more than 10,000 megawatts of electricity, the output of 10 nuclear reactors. Each megawatt supplies 760 typical homes.
“No chaos is ensuing,” Lynsey Paulo, spokeswoman for Pacific Gas and Electric Co., the state’s largest utility, said as the eclipse reached its 10:22 a.m. peak. “At this point, no issues. Steady as she goes.”
Using preliminary numbers, Schmitt said the amount of power lost from big solar facilities appeared to be roughly 3,000 to 3,500 megawatts — a manageable amount, given the reserves, and less than the Independent System Operator expected. (The loss would have been greater had the eclipse occurred in the middle of the day when solar power production peaks.)
While planning helped, so did the weather. The day proved relatively cool, with no summer heat wave to push up electricity demand. The Bay Area’s infamous fog, which thwarted many would-be eclipse watchers, kept down coastal temperatures.
The eclipse came and went before noon, a time when electricity demand is typically low.
In Folsom, Independent System Operator employees not keeping a sharp eye on the grid poured outside to gaze skyward, eyes shielded by special glasses. Some brought their children, hoisting them on shoulders for a clear view.
The air cooled as the light dimmed, until the sun’s shape had shrunk to a burning crescent.
“I’ve never considered myself a science geek, but I’m totally geeking out on this,” PG&E’s Paulo said.