The California Independent System Operator (ISO) on Sept. 3 issued a call for voluntary electricity conservation, with temperatures forecast above 100 degrees in the state over the weekend.
The “Flex Alert” starts Saturday, Sept. 5, and goes through Monday, Sept. 7, from 3p.m. to 9 p.m.
CAISO noted in a news release that Labor Day weekend temperatures are expected to be 10-20 degrees above normal for California.
The grid operator is predicting an increase in electricity demand, primarily from air conditioning use.
“Overnight temperatures statewide are projected to be at least 10 degrees higher than normal, which doesn’t allow infrastructure to cool down,” CAISO said.
Highlighting the benefits of conservation, the grid operator noted that consumer conservation activities during a heat wave last month were key to preventing expected power outages.
In a notice posted on its website on Sept. 3, CAISO said that in anticipation of the heat wave across California and the western states for trading days Sept. 5, 2020 through Sept. 7, 2020, it was seeking any available capacity the ISO can procure under its Capacity Procurement Mechanism or under a Section 42.1.5of its tariff which allows the CAISO to “take steps as it considers to be necessary to ensure compliance” with reliability criteria, “including the negotiation of contracts through processes other than competitive solicitations”.
To prepare for hot weather and high energy demand, CAISO on Sept. 2 issued a restricted maintenance order (RMO) from 6 a.m. Saturday-10 p.m. Sunday requiring generators and transmission operators to postpone outages for routine upkeep, so all available grid assets are online. On Sept. 3, the grid operator said that it was extending the RMO through Sept. 7.
The Weather Channel forecasted that Los Angeles would experience a high of 103 degrees on Saturday and 106 degrees on Sunday, while Sacramento is forecast to have a high temperature of 101 degrees on Saturday and 109 degrees on Sunday.
Sacramento, Calif., public power utility SMUD does not anticipate issues serving load, “barring some unforeseen circumstance like a transmission or generation interruption,” said Chris Capra, a SMUD spokesperson, on Sept. 3.
The public power utility will have a full complement of line personnel on hand to safely and quickly respond to unplanned outages, he said.
“We will likely ask our customers to conserve, if necessary, to keep stress on the system in check and to help them keep their bills down,” he said.
SMUD will continue to monitor conditions, Capra said.
Ellen Cheng, a spokesperson for the Los Angeles Department of Water and Power, said that "this weekend’s forecast through Tuesday sees loads approaching those of August 18 and 19. The difference is that the heatwave is not across the Western US, just in the Southwest, so imports from the North should not be an issue. We are sufficiently resourced for the weekend."
She added, "We’ll be able to support CAISO real-time, should they need it, through our additional energy capacity, available excess transmission capacity, and our reserves."
On Sunday and Monday "our support to CAISO will be more limited" due to extreme temperatures and near record breaking demand that is expected in Los Angeles, she said.