California ISO, CPUC and CEC issue final report on causes of rotating outages

The California Independent System Operator (CAISO), California Public Utilities Commission (CPUC) and California Energy Commission (CEC) on Jan. 13 issued a final root cause analysis of the August 2020 heat wave and rotating outages in the state.

On August 14 and 15, 2020, the CAISO was forced to institute rotating electricity outages in California in the midst of a West-wide extreme heat wave. Following these emergency events, California Gov. Gavin Newsom asked the CAISO, CPUC, and CEC to report on the root causes of the events leading to the August outages.

The CAISO, CPUC and CEC produced a preliminary report on October 6, 2020, and have since continued their analysis to confirm and supplement their preliminary findings.

The report released on Jan. 13 serves as the final root cause analysis and incorporates additional data analysis not available when the preliminary report was published.

The final root cause analysis confirms the preliminary report's findings that the three major factors leading to the August outages were related to extreme weather conditions, resource adequacy and planning processes, and market practices.

“This final root cause analysis provides important insights and lessons learned about the factors that contributed to the rotating power outages of last summer,” said CAISO President and CEO Elliot Mainzer in a statement. “As we prepare for summer 2021 and beyond, I look forward to working closely with the CPUC, CEC, policymakers and regional stakeholders to bring our planning, procurement and operational practices together into a modernized and well-integrated resource adequacy framework for California.”

In a jointly issued news release, the CAISO, CPUC and CEC said that since August, they have taken various actions “and continue focused efforts to prepare California for extreme heat waves next summer without having to resort to rotating outages.”

The CAISO, CPUC and CEC provided a number of examples related to those actions and efforts.

Among other things, the CPUC opened an emergency reliability rulemaking to procure additional resources to meet California’s electricity demand in summer 2021.

Through this proceeding, the CPUC has already directed the state’s three large investor-owned utilities to seek contracts for additional supply-side capacity and has requested proposals for additional demand-side resources that can be available during the net demand peak period (i.e., the hours past the gross peak when solar production is very low or zero) for summer 2021 and summer 2022.

The CPUC and parties to the proceeding, including the CAISO, will continue to evaluate proposals and procurement targets for both supply-side and demand-side resources.

The CPUC is also tracking progress on generation and battery storage projects that are currently under construction in California to ensure there are no CPUC-related regulatory barriers that would prevent them from being completed by their targeted online dates. The CAISO will continue to work with developers to address interconnection issues as they arise.

Meanwhile, the CAISO is continuing to perform analysis supporting an increase to the CPUC’s resource adequacy program procurement targets. Based on the analysis to date, the CAISO recommends that the targets apply to both the gross peak and the critical hour of the net demand peak period during the months of June through October 2021.

For its part, the CEC is conducting probabilistic studies that evaluate the loss of load expectation on the California system to determine the amount of capacity that needs to be installed to meet the desired service reliability targets.

In addition, the CAISO, CPUC, and CEC are planning to enhance the efficacy of Flex Alerts in the state to maximize consumer conservation and other demand side efforts during extreme heat events.

Also, preparations by the CAISO, CPUC, and CEC are underway to improve advance coordination for contingencies, including communication protocols and development of a contingency plan. “The contingency plan will draw from actions taken statewide under the leadership of the Governor's Office to mitigate the anticipated shortfall from August 17 through 19, 2020,” they said.

“Publicly owned utilities have been leaders in achieving the California’s aggressive clean energy and carbon reduction goals, and during the August event, POUs made significant power supply contributions to help the state avoid further widespread outages,” said Barry Moline, executive director, California Municipal Utilities Association. “Our emphasis has always been on maintaining the highest reliability and controlling costs. As we move forward, we’ll be working closely with California leaders to keep these objectives front and center to protect our customers.”

The final root cause analysis is available here.