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On October 13, 2025, the California Independent System Operator (CAISO) released its Draft Final Proposal for Interconnection Process Enhancements (IPE) 5.0—continuing its multi-year effort to modernize and streamline the interconnection process for new energy resources. The proposed reforms build on lessons learned from Cluster 15, previous IPE tracks, and stakeholder feedback.

Highlights of CAISO’s…

Update: Governor Newsom signed the Pathways Bill into law on September 19, 2025.

On September 13, 2025, Assembly Bill (AB) 825, titled the Independent System Operator: Independent Regional Organization Act, passed the California state Senate on a 34-0 vote, and a 74-1 approval in the Assembly.[1] The bill now heads to the Governor’s…

CAISO’s Interconnection Process Enhancements proposal faces protests from independent power producers, clean energy organizations, and renewable energy developers at FERC. Challengers claim that CAISO’s scoring criteria provide undue influence to load-serving entities (LSEs) and may violate principles of open access.

CAISO’s proposal addresses the backlog in its interconnection queue by prioritizing projects in zones with…

On Thursday, May 9, 2024, the California Independent System Operator (CAISO) issued an addendum to its Interconnection Process Enhancements (IPE) Track 2 Final Proposal, and issued a revised version of that addendum on May 17.  Track 2 focuses on modifications to the interconnection and queue management processes to address the substantial interconnection request volumes in…

Background

The California Independent System Operator’s (CAISO) recently issued Interconnection Process Enhancements (IPE) final proposal[1] provides heightened requirements to complete an interconnection request and relies on scoring criteria to determine which projects advance to the interconnection study process. Due to the proposed 150% cap on specific interconnection zones, not all interconnection requests in each…

Summary

On March 29, 2024, the California Independent System Operator (CAISO) released the Track 2 final proposal for its Interconnection Process Enhancements (IPE) initiative. The proposed changes in the IPE proposal aim to address the “unprecedented and unsustainable interconnection request volumes” in the CAISO.  CAISO proposes to adopt a zonal approach that prioritizes project interconnection in areas with existing or planned transmission capacity, to cap the number of projects permitted to proceed into the study process at 150% of the available and planned transmission capacity in specific zones, and adopt scoring criteria for eligibility and prioritization in the interconnection study process. 

Continue Reading CAISO Releases Interconnection Process Enhancements Final Proposal

On May 20, 2022, the California Public Utilities Commission (CPUC or Commission) issued a proposed decision (PD) that would, among other things, adopt Southern California Edison’s (SCE) 24-hour-slice proposal as the new resource adequacy (RA) framework applicable to load-serving entities (LSEs) under the CPUC’s jurisdiction.  Generally, the proposal would require each LSE to show that it has enough capacity to meet its specific gross-load profile, including a planning-reserve margin, or PRM, for all 24 hours for the “worst day” of each month.  The “worst day” would be defined as the day of the month that has the highest coincident-peak-load forecast.  This new RA framework would likely be implemented in 2025, with 2024 serving as a “test year” for the new framework.

The Commission initially began examining potential changes to its RA framework due to significant and ongoing changes in California’s generation-resource mix, with the increasing reliance on variable resources such as solar and wind, and use-limited resources, such as energy storage and demand response, as well as the retirement of older natural gas generation.  The Commission solicited proposals for a new RA framework starting in 2020, and in 2021 it tentatively adopted Pacific Gas and Electric’s (PG&E) slice-of-day proposal in decision 21-07-014.  The Commission ordered a series of workshops to further develop the proposal, culminating in a workshop report submitted March 1, 2022.  During the workshops, two alternate proposals were developed:  SCE’s 24-hour-slice proposal, and a two-slice proposal developed by Gridwell Consulting.  The parties generally favored one of the two alternate proposals, rather than the PG&E slice-of-day proposal.  The selection of SCE’s 24-hour-slice proposal will set the direction for further development of the new RA framework.
Continue Reading The California Public Utilities Commission Issues Proposed Decision on New Resource Adequacy Framework

On December 6, 2021, the California ISO issued an issue paper and straw proposal (“Straw Proposal”) for its Interconnection Process Enhancements stakeholder proceeding. The California ISO initiated this stakeholder proceeding on September 30, 2021 with the issuance of a preliminary issue paper. The stakeholder process comes at a time when an unprecedented level of energy procurement in California has caused dramatic increases in the number of projects in the California ISO’s interconnection queue. The California ISO’s most recent cluster, cluster 14, saw a record number of 373 interconnection requests being submitted, representing 150,000 megawatts of generating capacity, compared to 155 requests submitted in 2020. Ultimately, the volume of interconnection requests forced the California ISO to seek authority from the Federal Energy Regulatory Commission to extend its interconnection process by approximately one year.

The Interconnection Process Enhancements initiative will have two phases. Phase 1 will focus on near-term enhancements for cluster 14 and before the summer of 2022. The proposals in Phase 1 are scheduled be submitted to the California ISO Board of Governors in May 2022. Phase 2 will focus on longer term modifications and broader reforms to align interconnection processes with procurement activities. Those proposals are scheduled to be submitted to the Board in November 2022.
Continue Reading California ISO Issues Straw Proposal in Interconnection Process Enhancements Stakeholder Proceeding

On October 29, 2021, the California Public Utilities Commission (CPUC) issued three proposed decisions intended to address potential electric capacity shortfalls in 2022 and 2023.  The proposed decisions, if approved, would implement a variety of demand-side and supply-side policies designed to ensure that in the event of extreme weather during the summer of 2022 and/or 2023, California has sufficient electric capacity to avoid outages.

Background

In August 2020, the California ISO experienced outages during the evenings of August 14 and 15, and only extraordinary efforts, including voluntary conservation efforts by California energy users, allowed the California ISO to avoid outages the following week.

After those outages, the CPUC and the California Energy Commission (CEC) have been working towards addressing potential capacity shortfalls during extreme weather events during the summer.  In November 2020, the CPUC opened a rulemaking (R.20-11-003) to ensure reliability in the event of extreme weather during the summer of 2021.  In February 2021, the CPUC adopted a decision directing procurement of additional capacity (D.21-02-028), and in March, adopted a decision directing additional demand-side and supply-side actions to increase supply and decrease load during extreme weather events (D.21-03-056).

California managed to avoid outages during the summer of 2021, although it was helped by relatively mild weather in August and September.  A stack analysis performed by the CEC this summer, however, showed the potential for capacity shortfalls of up to 4,350 megawatts (MW) for summer 2022.  In August, the CPUC implemented a second phase to R.21-11-003, to ensure reliability during the summers of 2022 and 2023.
Continue Reading California Public Utilities Commission Takes Action to Prevent Outages During Summer 2022 and 2023