Cal-ISO board to address 2015-16 transmission plan, frequency response

The California ISO (Cal-ISO) board is scheduled to hold its next meeting March 24 and March 25, with decisions planned for March 25 on items that include the 2015-16 transmission plan and an effort to address frequency response.

The Cal-ISO on March 22 issued an agenda for the board meeting, with items on March 24 to include a briefing from the Department of Market Monitoring, personnel matters and a decision on long-term performance goals.

The 2015-16 transmission plan was recently revised from a draft plan. The revised plan, dated March 17, continues the trend of a declining amount of new transmission projects being identified and expanding the analysis of grid management issues associated with the transition from conventional generation resources to more renewable resources.

“This trend is partially offset by the need to address replacing aging infrastructure and the management of new concerns such as increasing demands on voltage control, which has driven much of the reinforcement projects identified in this plan,” the Cal-ISO said.

More opportunities for non-transmission alternatives, such as preferred resources and energy storage, continues to be a focus of the transmission planning analysis, the grid operator said. The focus on cleaner resources governs not only policy-driven transmission efforts, “but our path on meeting other electric system needs as well,” the Cal-ISO said in the 2015-16 transmission plan.

At more than 340 pages, the 2015-16 transmission plan identifies numerous transmission projects needed to maintain grid reliability and meet policy objectives, along with updates on expected in-service dates of previously approved projects.

The effort to address frequency response is the first phase of a longer term plan to improve the ability of grid operators to match supply and demand amid fluctuations or disturbances in generation and load.

In a proposal outlined in February, the Cal-ISO said it has seen “increasingly poor performance” on frequency response, mainly tied to the high penetration of renewable resources. The challenge for the Cal-ISO is that NERC’s frequency response grid reliability standard calls for compliance to begin Dec. 1, and a recent analysis showed that the grid operator met that standard in only four out of 25 events.

Among the solutions in the proposal was a plan to clarify internal generator requirements so that governor controls on equipment are in accordance with good utility practice with minimum governor performance settings, and having the Cal-ISO transfer a portion of its frequency response obligation to external balancing authority areas through a request for proposals process.

The Cal-ISO is not the only entity examining the performance of frequency response, with FERC in February issuing a notice of inquiry, seeking comment on whether it should alter generator interconnection requirements, call for existing generation units to provide frequency response services or establish market mechanisms that compensate generators for providing frequency response services.