WECC will take an interconnection-wide approach as it analyzes the events stemming from the mid-August record “heat storm” that prompted CAISO to initiate California’s first rolling blackouts since the energy crisis of 2000/01, officials said Tuesday.

The regional entity sees the effort as a “subset” of its larger, ongoing focus on resource adequacy in the Western Interconnection, WECC Vice President of Strategic Engagement Jordan White said during a call with stakeholders.

WECC signaled that direction last month when Director of Reliability Risk Management Vic Howell told a group of stakeholders that the RE would examine the developments of Aug. 15-18 as a Western “heat wave event” rather than just a California load-shed event when it performs its event analysis submitted to NERC. (See CalCCA Seeks ‘Objective’ Review of Blackout Report.)

“Although much of the focus [around the event] has been California because the customers in that state lost power, this truly was a West-wide heat event that prevented neighboring states from being able to export surplus power to California to avoid shutting firm load,” White said Tuesday.

From the perspective of many California residents and outside observers, the heat wave climaxed on Aug. 14 and 15 when CAISO was forced to cut power to about 812,600 households, representing about 2.4 million people.

The call for blackouts immediately sparked a wave of finger-pointing, with CAISO blaming the California Public Utilities Commission for managing a “broken” resource adequacy program. The CPUC countered that the state’s investor-owned utilities had procured sufficient resources to meet forecasts, and it questioned why those resources had not been available in the ISO market to meet the heavy demand. (See CAISO Blames Blackouts on Inadequate Resources, CPUC.)

CAISO, the CPUC and the California Energy Commission earlier this month jointly published a “root cause” analysis that largely attributed the blackouts to constraints on interties into California, under-scheduling by load-serving entities and ISO market design flaws, among other factors. (See CAISO Says Constrained Tx Contributed to Blackouts.)

“It’s important to understand that the heat wave was not just experienced in California; it was a wide-area heat wave event … that prevented neighboring states from being able to export their surplus energy to California,” Howell said. “This event really illustrates the importance of the resource adequacy discussions that have been happening at WECC and across the interconnection.” (See WECC Seeks to ‘Invent’ Future with RA Forum.)

Howell noted that the five-day event saw 28 energy emergency alerts (EEAs) issued across the Western Interconnection, 65% of the total issued for all of 2019. The alerts range from EEA-1, in which a balancing authority has already curtailed non-firm loads and is still concerned about meeting its contingency reserves requirement, to EEA-3, in which shedding for firm load is imminent or in progress in order to maintain that requirement.

Tim Reynolds, WECC’s manager of events analysis and situation awareness, recounted how the event unfolded, pointing out that on Friday, Aug. 14, only CAISO issued alerts, quickly jumping from an EEA-1 to EEA-3 before shedding 1,087 MW of load. On Aug. 15, CAISO issued an EEA-2 late in the afternoon that escalated to an EEA-3 around 7 p.m., leading to the shedding of 692 MW. Only one other balancing authority area — left unidentified by WECC — issued an alert (EEA-1) that day, just before CAISO initiated rotating outages.

The picture began to change on Monday, Aug. 17, when five unidentified Western BAAs issued EEA-1 warnings. CAISO again issued an EEA-3 but avoided shedding load because of conservation measures put in place.

On Aug. 18, four BAAs — including CAISO — entered EEA-3 at some point during the afternoon or evening. Another BAA issued an EEA-2 that evening. That day also saw the Western Interconnection’s summer peak demand of 162,000 MW (a figure WECC is still verifying), potentially beating the interconnection’s previous all-time peak set in July 2018 by 100 MW.

“What was every interesting was that on the 18th … there were a lot of things happening regarding energy conservation and other things coming into play, where the Western Interconnection didn’t have to shed any firm load,” Reynolds said. “So, going from the beginning of the heat wave to … Tuesday, there are some lessons that have happened, things that we want to get out there and let other people know.”

RA Side of Things

“This event is a new one for us and my team in particular,” said Matthew Elkins, manager of WECC’s performance analysis and resource adequacy efforts, referring to the fact that his group usually focuses on transmission system performance when it contributes to the RE’s events analyses.

“But this one was more about the resource adequacy side of things, so my team is excited to put that other hat on and really look at different things that we could do better,” including how WECC can improve its forecasts, he said.

Elkins presented a series of slides illustrating that, during most of the heat wave, CAISO’s demand far exceeded WECC’s 50/50 — and even 90/10 — forecasts for the period.

“Are our [forecasts’] range of possibilities really looking into what could occur?” Elkins said.

Meanwhile, CAISO’s renewable output came up far short of forecasts during the event. Elkins said WECC is interested in learning more about the performance of all resource types against forecasts. It also seeks to gather similar performance data from all Western BAAs.

“We want to understand what each of the areas were facing at that time, and more than just understanding if the energy was available. We can go through this and say, ‘Yeah, there was energy available somewhere in the system,’ but we have to be able to understand if there was transmission available to move that energy,” Elkins said.

He said one of the “great things” about the Western system is that its constituent BAs peak at different times, allowing for mutual assistance, but WECC wants to know how that practice could have been constrained during the heat wave.

“We’re not trying to point any fingers,” Elkins said. “What we’re trying to get out of this is really just a better understanding of how we can model a heat wave event … that really impacts so many balancing authority areas. Everyone was being impacted in some way, and I just to make sure our models are picking that up and we can look at these types of scenarios.”