Cal-ISO approves 13 transmission projects, addresses grid challenges

The California ISO (Cal-ISO) board on March 25 took several steps to improve grid operations, including approval of 13 transmission projects with a total estimated cost of $288m.

The Cal-ISO board also adopted measures calling for generators to improve frequency response performance in light of a NERC reliability standard that will take effect later this year, and heard from Cal-ISO President and CEO Steve Berberich on options for coordinating with the natural gas sector as a gas storage facility’s limited operations could affect gas supplies to generators this summer.

The 13 transmission projects include several relatively small facilities involving work at substations in the San Diego Gas & Electric (SDG&E) territory, a $10m Eagle Mountain shunt reactor project by Southern California Edison (SCE) and seven projects by Pacific Gas & Electric (PG&E). Four of the projects by PG&E are scheduled to be in service in December 2020, with the most expensive project slated to cost between $35m and $45m, according to a Cal-ISO presentation to the board.

None of the projects are eligible for the Cal-ISO’s competitive solicitation process, and no policy-driven or economically-driven transmission projects were identified in the plan, as all 13 of the projects are needed to address reliability, according to the presentation.

During the 2015-16 planning cycle, the Cal-ISO reviewed a number of projects to determine if they were still needed given changing load growth patterns, and that review led to the cancellation of 13 local sub-transmission projects in the PG&E territory, Berberich said in a March 17 report to the Cal-ISO board.

Due to progress made in previous planning cycles approving a wide array of transmission projects, the number of projects and cost of facilities approved in the 2015-2016 plan is considerably lower than in previous years, Berberich said. Any projects needed to address the higher renewable portfolio standard – 50% by 2030 – will be identified in future planning cycles, he told the board.

As TransmissionHub reported, the Aliso Canyon underground gas storage facility of Southern California Gas (SoCal Gas) is of limited use to the gas sector following a leak that has since been sealed, and state officials have been monitoring the situation since the facility is a key part of the gas system and is used to supply gas-fired power plants in the Los Angeles area.

Because SoCal Gas has limited ability to withdraw gas from the facility, the Cal-ISO is evaluating how daily gas balancing requirements, which could make it more costly or challenging for generators to nominate and stay within their required balancing limits for gas supplies, could affect generators’ ability to manage their assets.

In his report to the Cal-ISO board, Berberich said “a long list of mitigation options” are being pursued to minimize power grid reliability risks. Those options include increased use of demand response resources, close coordination between the Cal-ISO, utilities and gas pipeline operators and temporary changes in the timing of the Cal-ISO’s day-ahead market to better synchronize with gas markets, Berberich said.

Berberich also said that grid operators are experiencing challenges with managing load and generation swings as winter storms roll across coastal areas.

“In many cases, the storms result in higher wind output, lower solar output and higher loads because of the diminished distributed generation output due to cloud cover. Large system swings have occurred several times since the first of the year and have forced the ISO to carry more regulation reserves to avoid leaning on the rest of the Western Interconnect,” Berberich said in the report.

The act of balancing load and generation is at the heart of frequency response, which is being addressed in 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.

The Cal-ISO in February outlined how it has seen “increasingly poor performance” on frequency response, mainly due to the high penetration of renewable resources, which could be a problem since NERC’s frequency response grid reliability standard calls for compliance to begin Dec. 1.

The Cal-ISO board approved the initial step of having stronger requirements for all participating generators to provide frequency response services and having the Cal-ISO transfer a portion of its frequency response obligation to external balancing authority areas through a request for proposals. Transferring a portion of the frequency response obligation is allowed under the NERC reliability standard, according to the Cal-ISO presentation to the board.

The Cal-ISO will monitor frequency response performance and consider more comprehensive solutions that could include development of a new frequency response product in the future, according to the presentation.

SDG&E and SoCal Gas are subsidiaries of Sempra Energy (NYSE:SRE), while SCE is a subsidiary of Edison International (NYSE:EIX) and PG&E is a subsidiary of PG&E Corp. (NYSE:PCG).