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

By Sean Rai-Roche
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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.

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