CAISO drafts 20-year plan to get California on-track for 100% renewables

By Sean Rai-Roche
LinkedIn
Twitter
Reddit
Facebook
Email
Saticoy, a 100MW/400MWh battery project commissioned in California in 2021. Image: Courtesy of Arevon.

California’s energy transition will need 53GW of solar PV by 2045, with the state’s transmission system requiring a US$30.5 billion investment alongside major increases in energy storage to accommodate the extra power.  

A draft version of California ISO’s (CAISO) 20-Year Transmission Outlook report providing a roadmap for the next two decades and a draft 2021-2022 Transmission Plan covering the next 10 years, was issued today. 

It outlined that by 2045, the state would require 53GW of utility-scale solar, 37GW of battery energy storage systems (BESS), 4GW of long-duration storage and more than 2GW of geothermal, alongside 24GW of wind power reserves, all of which need to be connected to the grid.

Created in collaboration with the regulatory California Public Utilities Commission (CPUC) and the state government’s California Energy Commission, the draft plan will be voted on in March by CAISO’s Board of Governors.

This article requires Premium SubscriptionBasic (FREE) Subscription

Try Premium for just $1

  • Full premium access for the first month at only $1
  • Converts to an annual rate after 30 days unless cancelled
  • Cancel anytime during the trial period

Premium Benefits

  • Expert industry analysis and interviews
  • Digital access to PV Tech Power journal
  • Exclusive event discounts

Or get the full Premium subscription right away

Or continue reading this article for free

To read the full version of this story, visit PV Tech.

Read Next

June 15, 2026
APAC’s AI data centres look set to lock in a decade of coal and gas dependency, but long-duration energy storage can break that cycle, says Pavina Adunratanasee of ArkTerra Partners.
June 12, 2026
RWE Renewables Australia has officially opened the 50MW/400MWh Limondale battery energy storage system (BESS) near Balranald in south-west New South Wales.
June 11, 2026
DNV has independently verified that Fluence’s global fleet of battery energy storage systems (BESS) achieved 98.7% MW-weighted availability.
June 10, 2026
EDP and SRP complete 200MW/800MWh Arizona BESS, Pathway Power closes $150m facility, and B2U secures Waymo supply deal for second-life EV batteries in grid storage.
Premium
June 9, 2026
ESN Premium speaks with Dr Thomas Sisto, of flow battery developer XL Batteries, about using LDES to combat grid strain from heatwaves and data centres.