Cal-ISO board approves $142M transmission plan for reliability needs

Houston — The California Independent System Operator board of governors approved on Wednesday the 2019-20 Transmission Plan that identified nine transmission projects to address grid reliability requirements at a cost of $141.7 million.

Of the nine projects listed in the plan, seven already have been approved by ISO management. The additional two were reliability-driven transmission projects identified as needed to ensure compliance with NERC and ISO planning standards.

"In arriving at these projects, the ISO and transmission owners performed power system studies to measure system performance against the NERC reliability standards and ISO planning standards, as well as to identify reliability concerns that included, among other things, facility overloads and voltage excursions," according to the plan memorandum. "The ISO then evaluated mitigation measures and identified cost-effective solutions."

Seven of the projects are located in the PG&E service territory and are expected to cost $120.7 million. One of the projects is in the SCE service territory and will cost $5 million, and another project is in the Valley Electric Association/GridLiance West service territory and will cost $16 million.

While no economic-driven projects were identified, one of the reliability-driven projects is recommended to be advanced for economic benefits as well.

There were also three projects identified to be put on hold for further evaluation in future planning cycles. Those include upgrades north of Mesa, the Moraga-Sobrante 115 kV line reconductor project and the Wheeler Ridge Junction Station project. All are located in the PG&E service territory.

Background

Every year the ISO takes a comprehensive look at the transmission needs of the system over a 10-year planning period to produce the annual transmission plan.

No policy-driven projects were recommended in the plan since a significant number of policy-driven transmission projects were approved in past planning cycles to meet the state's renewable portfolio standard goals.

"While no new opportunities for storage were recommended for approval in this transmission plan, a significant number were studied for possible benefits," according to the plan memorandum. "The ISO is also continuing to work with the local utilities to fine-tune preferred resource requirements, including battery storage, which in conjunction with conventional transmission upgrades will meet reliability needs in several areas – Moorpark and Oakland in particular."