Brace yourself for a long, hot summer — and the possibility of electricity shortages.
The managers of California's electrical grid warned Wednesday that the state is facing tight power supplies this summer, due in part to a drier winter that is reducing available hydro power. Some Californians could be forced to turn down their air conditioners, hold off on doing their laundry or make other sacrifices in the name of energy conservation.
The California Independent System Operator, in its annual summer forecast, said there's "an extremely low probability" that it will have to order rolling blackouts this summer. But there's a 50 percent chance that the ISO will have to declare a "Stage 2" emergency for the first time since 2007.
Under Stage 2, consumers who have signed up for incentive rates could be required to use less electricity during late afternoons and early evenings, when electricity usage hits its peak.
This includes customers, for instance, who have enrolled in PG&E's "Smart AC" program, which gives consumers a $50 payment but allows the utility to remotely adjust their air conditioners when supplies get tight, said Pacific Gas and Electric Co. spokesman Denny Boyles.
He said most customers don't notice their air conditioners are being adjusted. "At most it's a 1- to 3-degree change in the temperature in their homes," he said.
Although it's not part of the Independent System Operator's grid, SMUD operates a similar program, called "Peak Corps," that pays participating customers a $5 bonus every time the utility adjusts their air conditioning.
"We have not used it ... for close to 15 years," said spokesman Jonathan Tudor of the Sacramento Municipal Utility District. "It's an emergency-only program." He added that SMUD believes the overall supply outlook for this summer is good, but "things could change, as they often do.
Before it gets to a Stage 2 emergency, the Independent System Operator will issue "Flex Alerts" urging consumers to postpone laundry or adjusting their thermostats. It also can shut off power intermittently to businesses that have signed up for incentive programs and order power-plant owners around the state to ramp up plants that have been sitting in reserve.
Any talk of power shortages conjures up memories of the 2001 energy crisis, when the state endured several days of rolling blackouts and became something of a national laughingstock. Analysts say California's energy supply system is far more robust these days, thanks to a power-plant construction boom and a major rise in solar and other renewable sources.
Still, this summer's forecast is sobering. It contrasts with last year's, when the state's utilities breezed through a series of extended heatwaves with relatively few problems. A big difference: Last summer the state was blessed with an abundance of hydro power, thanks to the wettest winter in Northern California history. Hydro power can generate as much as 25 percent of the state's electricity in a typical year.
This year is a different story. Despite a fairly rainy March, the Independent System Operator forecasts a 42 percent decline in available hydro supplies, said ISO spokeman Steven Greenlee. That's a decline of 1,300 megawatts, enough to power more than 1 million homes.
While California's big reservoirs are in good shape, the smaller reservoirs "are well below normal," Greenlee said. And that's where the lion's share of the state's hydro power is generated, he said.
Another problem: About 800 megawatts' worth of natural-gas plants have been retired in the past year. Although most of that power has been replaced by a surge in solar farm construction and biofuel plants, the new plants tend to be in remote areas. The electricity has to be piped into the state's urban areas, which can strain the power system.
"We'll have to import that electricity to serve those local areas; we'll have to deal with transmission capacity and congestion," Greenlee said.