The California Independent System Operator (CAISO) anticipated initiating rotating power shut-offs again on Tuesday, but none were initiated in San Diego.
CAISO said it would issue a Stage 3 Emergency, like it has in three of the previous four days, and tell local utilities if outages were imminent but San Diego Gas & Electric was never notified.
If a Stage 3 Emergency is ordered in the future, customers whose circuit numbers are listed here will be affected. To determine if you live in one of the grids affected, check your SDG&E bill for your circuit number and compare it to the list once a rotating outage is announced.
The agency applauded Californians for evening energy conservation efforts that saved parts of the state from experiencing outages between 4 and 5 p.m.
SDG&E said it's dealing with the "perfect storm" of threats to its electrical grid. One variable customers might not be aware of is extreme temperatures in nearby states like Washington and Arizona, which is where some of our power comes from. When those states deal with high heat, it's harder for them to send us power.
Another issue is local cloud cover due to a tropical storm off the coast of Baja California which hinders solar power harvesting, which is a major contributor to the grid.
And finally, more people are at home due to the pandemic, so very few people are leaving their house to beat the heat and are instead staying home, adding to overall power demand.
Rotating outages ordered last Friday were the first in nearly two decades. They came at the onset of a heat wave that sent energy usage soaring and strained California's electricity systems.
"Although a Stage 3 Emergency is a significant inconvenience to those affected by rotating power interruptions, it is preferable to manage an emergency with controlled measures rather than let it cause widespread and more prolonged disruption," CAISO said.
SDG&E was notified about rotating outages in its service area Monday but said residents did well enough conserving energy during peak hours to avoid any blackouts.
During a rotating outage, about 100,000 San Diego Gas & Electric customers at a time may have their power cut off for about an hour. SDG&E will simultaneously cut power to about a half-dozen grids before moving on to another half-dozen the following hour.
California is under a Flex Alert through Thursday -- a voluntary call to conserve energy usage between 3-10 p.m. -- which can help avoid entering the next level of emergency.
SDG&E said that, to avoid rotating outages in the future, energy conservation is "urgently needed."
"Energy conservation remains essential to help avoid the need for rotating outages, as well as the duration of outages and the number of customers affected. Everyone is urged to do their part to cut back on energy use during this critical time," the agency said.
The CAISO offered a series of tips to conserve power, including:
- Turning off unnecessary lights
- Using major appliances before 3 p.m. and after 10 p.m.
- Setting air conditioner thermostats to 78 degrees or higher
- Using fans and keeping drapes drawn
- Reducing the use of pool pumps
SDG&E also recommends that residents have flashlights and batteries. Those who rely on electric or battery-dependent medical technologies, such as breathing machines, power wheelchairs/scooters, and home oxygen or dialysis, should be prepared to activate their emergency plan.
More energy-saving tips can be found on the FlexAlert website.
San Diego County and the majority of the state were in the midst of a brutal heat wave that was sending temperatures into triple digits. An excessive heat warning set to expire on Monday was extended until Thursday in San Diego County.