The California Independent System Operator issued a statewide Flex Alert, a call for voluntary electricity conservation, beginning Sunday and extending through Wednesday.
The Flex Alerts are in effect from 3 p.m. to 10 p.m. each day, Cal-ISO said.
"A persistent, record-breaking heat wave in California and the western states is causing a strain on supplies, and consumers should be prepared for likely rolling outages during the late afternoons and early evenings through Wednesday," the agency said. "There is not a sufficient amount of energy to meet the high amounts of demand during the heat wave.
"However, consumers can actively help by shifting energy use to morning and nighttime hours and conserving as much energy as possible during the late afternoon and evening hours."
At 2:30 p.m., the Cal-ISO electrical grid status showed demand statewide was at 40,648 megawatts, with total capacity at 53,336 mw and the forecast peak at 45,669 mw. A megawatt is a unit of power equal to one million watts.
The ISO issued a statewide Flex Alert, a call for voluntary electricity conservation, today through Wednesday, 3 to 10 p.m. each day. Record-breaking heat is straining supplies; consumers should plan for potential outages. https://t.co/qaxmGA5suu pic.twitter.com/KiDlDdkrwm
— California ISO (@California_ISO) August 16, 2020
The agency said consumer conservation can help lower demand and avoid further actions including outages, and lessen the duration of an outage.
"Consumers are urged to lower energy use during the most critical time of the day, 3 p.m. to 10 p.m., when temperatures remain high and solar production is falling due to the sun setting," Cal-ISO said. "Extended periods of heat also can cause generator equipment failures that can lead to more serious unplanned losses of power."
Between 3 p.m. and 10 p.m., the ISO is urging consumers to:
— Set air conditioning thermostats to 78 degrees, if health permits;
— Defer use of major appliances;
— Turn off unnecessary lights;
— Unplug unused electrical devices;
— Close blinds and drapes and;
— Use fans when possible.
RELATED: Stage 3 Electrical Emergency Called Statewide For 20 Minutes
Consumers can also take steps to prepare for the Flex Alert by doing the following before 3 p.m.:
"Pre-cool" their homes, or lower air conditioning thermostats to 72 degrees, charge electric vehicles, charge mobile devices and laptops, run dishwashers, washing machines and other major appliances and set pool pumps to run in the early morning or late at night.
Cal-ISO declared an emergency at 6:28 p.m. Saturday for about 20 minutes, when rotating power outages occurred in some areas in San Diego County, many in North County.
Outages occurred in parts of Carlsbad, Escondido, Del Mar, El Cajon, Point Loma, Torrey Pines, Fletcher Hills, San Marcos and Mira Mesa.
"The load was ordered back online 20 minutes later as wind resources increased," Cal-ISO said. "Extreme heat throughout the West has increased electricity usage, causing a strain on the power grid. All available resources are needed to meet the growing demand."
