• After the 2020 summer’s shortfall and continuing tight capacity conditions experienced in the previous years, CAISO, together with the California Energy Commission (CEC), and California Public Utilities Commission (CPUC), recently issued its first 20-Year Transmission Outlook.166 In order to address grid reliability concerns and incorporate the additional energy, transmission infrastructure projects needed in the next two decades have been identified. From Base portfolio 2031 to 2040 (using SB100 starting point scenario), renewables resources and battery storage are expected to expand by an average of 346 percent—while pumped Hydro and Long-duration energy storage share the same growth rate of 538 percent, dominating the growth plan. Currently, the California energy system’s peak capacity is about 50,000 MW. The planning assumptions of the state call for adding 120,000 MW of new, clean capacity by 2040. During the summer heat wave in September 2022, the state reported its transmission connections to the Pacific Northwest alone can carry 10-times as much power (7,900 MW) as all of Texas’s very limited interconnections, and were largely full with 5,500 MW to 7,500 MW surging during the highest demand period.167 Furthermore, the CPUC authorized 25,500 MW of new supply-side renewables and 15,000 MW of new storage and demand response resources by 2032, enough clean energy to power approximately 11.5 million homes.168

166 The California Independent Operator. Draft 20-Year Transmission outlook. January 31, 2022. Retrieved from: http://www.caiso.com/InitiativeDocuments/Draft20-YearTransmissionOutlook.pdf

167 NRDC. The Great California Electricity Blackout that wasn’t. September 12, 2022. Retrieved from: https://www.nrdc.org/experts/ralph-cavanagh/great-california-electricity-blackout-wasnt

168 The California Utilities Commission. CPUC Approves Long Term Plans To Meet Electricity Reliability and Climate Goals. February 10, 2022. Retrieved from: https://www.cpuc.ca.gov/news-and-updates/all-news/cpuc-approves-long-term-plans-to-meet-electricity-reliability-and-climate-goals.