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CA — Power Infrastructure Updated January 2026

California

CAISO Nuclear Natural Gas Solar Wind Storage Data Center PPAs Queue Bottlenecks Transmission Constraints

Overview

California is building the foundation for a high-renewable grid while managing the reality that today’s large loads still draw from natural gas reliability backstops. The state has extended the life of Diablo Canyon nuclear, set planning goals for 25 GW of offshore wind by 2045, and deployed over 8,500 MW of battery storage. CAISO’s 2024-2025 transmission plan commits $4.8 billion to 31 new projects, but lead times of eight to ten years and a 33 GW interconnection queue create bottlenecks for both new generation and new data center loads.

Generation Projects

Nuclear

Diablo Canyon extension (San Luis Obispo County): The state is pursuing a limited-term extension of Diablo Canyon’s operating license, supported by a $1.1 billion DOE Civil Nuclear Credit Program award.[1]

Natural Gas

Gas remains a reliability backstop while new transmission and clean resources build out. The CEC’s power plant listing shows major gas plants like the 300-MW Pio Pico Energy Center as operational — the reality new large loads would draw from today.[2] New gas builds are limited; there are no major new gas Application for Certification (AFC) or opt-in projects in the current CEC queue comparable to the scale of new solar and storage projects.[2][3]

Solar

Soda Mountain Solar Project (San Bernardino County): Proposed 300-MW PV plus up to 300-MW/1,200-MWh battery storage; project status under review in the CEC opt-in process.[4]

Wind

California is planning a major offshore wind buildout. The CEC’s July 2024 strategic plan sets planning goals of 2,000-5,000 MW by 2030 and 25,000 MW by 2045.[5] CAISO’s 2024-2025 transmission plan includes 4.5 GW of offshore wind (2.9 GW Central Coast, 1.6 GW North Coast) as part of its buildout scenarios.[6]

Transmission and Grid

CAISO’s 2024-2025 Transmission Plan includes 31 new reliability and policy-driven projects totaling an estimated $4.8 billion.[6] Bay Area upgrades tied to load growth include a new Greater Bay Area 500-kV line, a San Jose B–Northern Receiving Station 230-kV line, South Bay 115-kV reconductoring, and North/South Oakland 115-kV upgrades.[6]

CAISO notes project lead times up to eight to ten years, which aligns with data center interconnection timelines.[6] The plan targets transmission to import over 9 GW of out-of-state wind and integrate 4.5 GW of offshore wind.[6]

Battery Storage

As of October 2023, the CEC reports more than 6,600 MW of battery storage online, with another 1,900 MW expected by year-end for about 8,500 MW total.[7]

Key projects under review:

  • Compass Energy Storage Project (San Juan Capistrano): 250-MW / 1,000-MWh battery project (CEC opt-in).[8]
  • Corby Battery Energy Storage System (Solano County): 300-MW / 1,200-MWh battery project (CEC opt-in).[9]
  • Willow Rock Energy Storage Center (Kern County): 500-MW net / 4,000-MWh net compressed-air storage project (CEC AFC) — a large long-duration resource relevant to overnight data center loads.[10]

Data Center Power Agreements

Apple (Direct Access + California Flats Solar Project): Apple reports that its California data centers, offices, and stores receive renewables from the California Flats solar project through Direct Access contracts with third-party power providers.[11]

No other California-specific PPAs by major hyperscalers are disclosed in public state filings. Many corporate PPAs are signed for out-of-state projects and do not directly add CAISO capacity, which likely limits near-term options for California data center load growth.

Interconnection Queue

CAISO’s Cluster 15 queue report shows 97 California projects totaling approximately 33.2 GW net MW POI. The projects are dominated by battery storage (52) and solar (40).[12]

CAISO’s generator interconnection process runs via clustered studies and publishes queue data by cluster, with earlier clusters in the Renewable Integration Market Simulation (RIMS) system.[3] The queue mix implies heavy competition for transmission capacity and deliverability upgrades, and CAISO’s plan notes eight-to-ten-year lead times for major transmission builds.[6][3]

What to Watch

  • Offshore wind lease development and transmission interconnection timelines for 2030 and 2045 targets.
  • Bay Area transmission upgrades tied to load growth — whether these projects stay on schedule given eight-to-ten-year lead times.
  • Cluster 15 queue progression and whether CAISO implements further interconnection process reforms to address the 33 GW backlog.

Sources

[1] Governor of California. “Governor Newsom Statement on Federal Funding for Diablo Canyon Extension.” Press release, November 21, 2022. https://www.gov.ca.gov/2022/11/21/governor-newsom-statement-on-federal-funding-for-diablo-canyon-extension/. Accessed January 8, 2026.

[2] California Energy Commission. “Pio Pico Energy Center.” Power plant page. https://www.energy.ca.gov/powerplant/simple-cycle/pio-pico-energy-center. Accessed January 8, 2026.

[3] California Independent System Operator. “Generator interconnection.” https://www.caiso.com/generation-transmission/generation/generator-interconnection. Accessed January 8, 2026.

[4] California Energy Commission. “Soda Mountain Solar Project.” Project page (CEC Opt-In), August 2025. https://www.energy.ca.gov/powerplant/solar-photovoltaic-pv-battery-energy-storage/soda-mountain-solar-project. Accessed January 8, 2026.

[5] California Energy Commission. “CEC Adopts Offshore Wind Energy Strategic Plan to Support California’s 100% Clean Electricity Future.” Press release, July 10, 2024. https://www.energy.ca.gov/news/2024-07/cec-adopts-offshore-wind-energy-strategic-plan-support-californias-100-clean. Accessed January 8, 2026.

[6] California Independent System Operator. 2024-2025 Transmission Plan (Board Approved). May 30, 2025. https://www.caiso.com/documents/iso-board-approved-2024-2025-transmission-plan.pdf. Accessed January 8, 2026.

[7] California Energy Commission. “California Sees Unprecedented Growth in Energy Storage, A Key Component in the State’s Clean Energy Transition.” Press release, October 24, 2023. https://www.energy.ca.gov/news/2023-10/california-sees-unprecedented-growth-energy-storage-key-component-states-clean. Accessed January 8, 2026.

[8] California Energy Commission. “Compass Energy Storage Project.” Project page (CEC Opt-In), May–June 2025. https://www.energy.ca.gov/powerplant/battery-storage-system/compass-energy-storage-project. Accessed January 8, 2026.

[9] California Energy Commission. “Corby Battery Energy Storage System Project.” Project page (CEC Opt-In), November 2025. https://www.energy.ca.gov/powerplant/battery-storage-system/corby-battery-energy-storage-system-project. Accessed January 8, 2026.

[10] California Energy Commission. “Willow Rock Energy Storage Center.” Project page (CEC AFC), 2025. https://www.energy.ca.gov/powerplant/energy-storage-system/willow-rock-energy-storage-center. Accessed January 8, 2026.

[11] Apple Inc. Apple Environmental Progress Report 2024. April 2024. https://www.apple.com/environment/pdf/Apple_Environmental_Progress_Report_2024.pdf. Accessed January 8, 2026.

[12] California Independent System Operator. Cluster 15 Interconnection Requests (XLSX). December 16, 2025. https://www.caiso.com/documents/cluster-15-interconnection-requests.xlsx. Accessed January 8, 2026.