In a stakeholder call yesterday, the CAISO discussed the Revised Draft Final Proposal in the Generator Deliverability Assessment stakeholder initiative. During the call, the CAISO addressed outstanding stakeholder questions, including confirming key upcoming dates for project developers.

Background on the Proposal

The CAISO is proposing revisions to its deliverability assessment methodology in response to the rapid increase in the amount of solar resources and the California Public Utilities Commission’s (CPUC) resulting transition to an Effective Load Carrying Capability (ELCC) approach to calculating qualifying capacity (QC). The CAISO’s revisions are intended to more closely align the capacity studied in the deliverability assessment with the generator’s anticipated QC under the CPUC’s new ELCC methodology. Under the current deliverability assessment methodology, generators are studied at a higher capacity than the projects can qualify for under the ELCC methodology. Under the revised deliverability methodology, projects are expected to retain their full capacity deliverability status (FCDS) and their NQC value will not be reduced, but the proposed change should be beneficial to future interconnection customers because it will free up some unused deliverability and likely result in fewer required network upgrades to receive FCDS.

As part of the proposal the CAISO is also creating a new sub-status for solar and wind projects: Off-Peak Deliverability Status (OPDS). New solar and wind OPDS resources will receive market scheduling priority by continuing to be allowed to self-schedule as an incentive for resources to develop in locations that do not trigger upgrades or trigger only low-cost localized transmission upgrades.

One-Time TPD Deliverability Allocation

As a result of the proposed change, the CAISO will allocate newly freed deliverability through a one-time Transmission Plan Deliverability (TPD) Allocation, which will include an option for energy-only projects currently in the queue to elect OPDS. Projects will be allocated the newly freed capacity in a pre-identified priority order based on queue cluster, PPA status, project stage, and other factors. The “Seeking TPD” Affidavit is due on December 3, 2019 for energy-only or partial capacity deliverability status projects and will include two sections: one assuming FERC does not approve the one-time TPD change and additional information assuming FERC approves the one-time TPD change. Both sections must be completed.

Adding Storage at Existing or New Generation Sites

Some interconnection customers with existing queue positions that have been studied at higher levels of deliverability under the current methodology (generally solar generation, which would have been studied with a higher deliverability than its current QC under the CPUC’s new ELCC approach) have expressed an intention to submit a Material Modification Assessment (MMA) request to convert some of their interconnection to storage and transfer some deliverability.  The current deliverability methodology will determine how much deliverability can be transferred, but deliverability after the transfer will be determined under the new proposed methodology.  With some basic calculations, the original project can retain enough deliverability to maintain FCDS, while transferring excess deliverability to the added storage.

The MMA request must be submitted by December 2, 2019. However, following stakeholder input on the short timeline to pull together materials, the CAISO has extended the timeline for validation through March 15, 2020.

Next Steps:

The CAISO anticipates developing tariff language quickly in order to file the proposed revisions with FERC in the first week of December 2019. Project developers should pay close attention to the CAISO’s deadlines as the transition to the new methodology takes place.