California ISO (Cal-ISO) management, in the March 8 revised draft 2016-2017 Transmission Plan, requests that the Cal-ISO Board of Governors approve two reliability driven transmission projects identified as needed to ensure compliance with NERC and Cal-ISO planning standards, Cal-ISO President and CEO Steve Berberich said in a March 9 memorandum to the board.
Those projects have an estimated cost of about $24m and are not eligible for competitive solicitation, he said.
The transmission plan provides a comprehensive evaluation of the Cal-ISO-managed transmission grid to identify upgrades needed to successfully meet California’s policy goals, grid reliability requirements, and to provide economic benefits to consumers, Berberich noted.
Continuing the recent trend of prior transmission plans, the number and capital costs of recommended transmission projects in the 2016-2017 plan are considerably less than in previous years, as no significant new projects are required on the system under any of the categories, he said.
No policy driven or economic-driven transmission projects were identified as needed, he said.
A review of previously approved transmission projects – given material changes in circumstances underpinning the original need for the projects – was included in the plan, and resulted in the cancellation of 13 projects in the PG&E service area, as well as certain other previously approved projects being placed on hold pending further review in the 2017-2018 planning cycle, Berberich said.
According to the report, the two transmission projects that the Cal-ISO determined were needed to mitigate identified reliability concerns are:
- The $6m Big Creek Rating Increase Project in the Southern California Edison (SCE) service area that has an expected in-service date of Dec. 31, 2018
- The $18m Lugo-Victorville 500-kV Upgrade (SCE portion) in the SCE service area that has an expected in-service date of December 2018
Of the Big Creek Corridor Rating Increase Project, the report said that the project was submitted by SCE to achieve capacity increases building upon other activities that the company is undertaking for purposes that are not subject to the Cal-ISO’s transmission planning purposes.
In early 2016, SCE decided to reconductor the Magunden-Vestal No. 1 and No. 2, as well as the Rector-Vestal No. 1 and No. 2 230-kV lines in the Big Creek corridor using an aluminum conductor composite core (ACCC) conductor (714 kcmil “Dove”) as part of the Transmission Line Rating Remediation (TLRR) program coordinated with the California Public Utilities Commission (CPUC) to address certain clearance issues, the report said. Those circuits are among the locations on SCE’s Cal-ISO-controlled overhead transmission lines that did not meet clearance requirements per a CPUC general order that SCE provided to NERC in January 2011, the report said.
SCE proposed the project into the 2016-2017 planning cycle, which will increase the conductor rating of the Magunden-Vestal No. 1 and No. 2, as well as the Rector-Vestal No. 1 and No. 2 230-kV lines in the Big Creek Corridor from a four-hour emergency capacity of 936 camps to 1520 amps, the report said.
The planning level scope includes the upgrade of four transmission structures and terminal equipment at the Magunden and Vestal substations, the report said, adding that the increase in ratings will eliminate the P1 (N-1) load shed during low hydro conditions.
Of the Lugo-Victorville 500-kV Upgrade (SCE portion) project, the report said that overloading on that 500-kV line was observed for several N-1-1 contingencies involving 500-kV lines bringing power into the Lugo 500-kV and the Devers 500-kV substations. The line would also be overloaded following the Eldorado-Lugo 500-kV single line outage in the 2021 summer peak heavy renewable sensitivity case.
The report added that the 33% renewables portfolio standard (RPS) policy driven studies documented in the Cal-ISO’s 2015-2016 Transmission Plan also identified the facility as a limiting constraint for delivering resources from multiple renewable zones.
While the project was found to be needed in the 2015-2016 Transmission Plan, the Cal-ISO deferred approving the project until the 2016-2017 transmission planning cycle, pending coordination with the Los Angeles Department of Water & Power (LADWP), which owns a portion of the line, the report said. Over the course of last year, the Cal-ISO worked with SCE and the LADWP to coordinate the next steps on developing the project.
The report added that recognizing the benefit to the LADWP – which led to the LADWP’s interest in funding its portion of the upgrades – SCE and the LADWP proposed to increase the rating of Path 46 West of the Colorado River (WOR) through the Western Electricity Coordinating Council path rating process last October.
That path rating increase will be made possible because the LADWP and SCE are pursuing upgrade projects that involve existing transmission facilities on their respective transmission systems, including the joint project to upgrade the Lugo-Victorville 500-kV line, along with SCE upgrading series capacitors on its Northern WOR 500-kV transmission lines, and the LADWP upgrading series capacitors on its WOR 500-kV transmission lines, the report said.
Projects no longer required
According to the report, the 13 projects that the Cal-ISO found are no longer required based on reliability and local capacity requirements and deliverability assessments, and that the Cal-ISO recommends cancelling are:
- Pease-Marysville #2 60-kV Line
- Almaden 60-kV Shunt Capacitor
- Monta Vista-Los Gatos-Evergreen 60-kV Project
- Lockheed No. 1 115-kV Tap Reconductor
- Mountain View/Whisman-Monta Vista 115-kV Reconductoring
- Stone 115-kV Back-tie Reconductor
- Kearney-Kerman 70-kV Line Reconductor
- Cressey-North Merced 115-kV Line Addition
- Taft-Maricopa 70-kV Line Reconductor
- Natividad Substation Interconnection
- Soledad 115/60-kV Transformer Capacity
- Tesla-Newark 230-kV Path Upgrade
- Vaca Dixon-Lakeville 230-kV Reconductoring
The report also noted that several other projects are in the late stages of design, siting and permitting, and that continuing the design, siting and permitting activities will assist in the review. However, the report said, the Cal-ISO is recommending that the project sponsors do not proceed with filings for permitting and certificates of public convenience and necessity for these projects until the Cal-ISO completes the reviews:
- Midway-Andrew 230-kV Project
- Spring Substation
- Wheeler Ridge Junction Substation
- Lockeford-Lodi Area 230-kV Development
- Vaca-Davis Voltage Conversion Project
For these projects, the report said, all development activities are recommended to be put on hold until a review is complete:
- Gates-Gregg 230-kV Line
- Watsonville Voltage Conversion
- Atlantic-Placer 115-kV Line
- Northern Fresno 115-kV Area Reinforcement
- South of San Mateo Capacity Increase
- Evergreen-Mabury Conversion to 115-kV
- New Bridgeville Garberville No. 2 115-kV Line
- Cottonwood-Red Bluff No. 2 60-kV Line Project and Red Bluff Area 230-kV Substation Project
- Kern PP 115-kV Area Reinforcement
- Wheeler Ridge-Weedpatch 70-kV Line Reconductor
Of the Gates-Gregg 230-kV Line Project, for instance, the report said that the Cal-ISO approved the project in the 2012-2013 transmission planning process as a reliability driven project with renewable integration benefits. The need for the line was to increase the pumping opportunities at the Helms pumped storage/generation facility to ensure that there would be adequate water available when the generation was called upon to support local area loads, the report said.
The 2012-2013 transmission planning process identified that the availability of pumping would begin to decrease in the 2023 timeframe with inadequate pumping opportunities to provide sufficient water for generation to meet reliability needs in the Fresno local area by the 2029 timeframe, the report said.
In this planning cycle, the Cal-ISO reassessed the need for the line using the assumptions in the 2016-2017 transmission planning process based upon the California Energy Commission 2015 Integrated Energy Policy Report energy and demand forecast that reflected a lower load forecast and increased behind the meter photovoltaic (PV) generation, the report said. The resulting lower forecast in the area potentially would allow for increased pumping capability, thus reducing the reliability need for local area support from the Helms generation to maintain reliability, the report said, noting that the Cal-ISO’s analysis indicates that the changed factors defer the reliability need by about 10 years.
In addition, increased behind the meter PV has changed the load profile in the area and would allow increased pumping during the day time periods, the report said, adding that there are also uncertainties regarding renewable integration needs, which need to be assessed further and taken into account.
Among other things, Berberich noted in his memorandum that the plan included a number of special studies pertaining to key emerging issues, including studies on the risk of natural gas generator retirements, gas/electric coordination, transmission needs for various 50% RPS portfolios, and the benefits of large-scale energy storage. He said that all of those studies are informational only, and several are the subject of further study.