Transition Cluster Study

This page provides information about the Transition Cluster Study. The Transition Cluster Study is governed by Attachment R to BPA’s Open Access Transmission Tariff and the Transition Process Business Practice

Transition Cluster Schedule

Cluster Study Participants:

(show bar charts: # of requests, Ix Service Lvl, Nameplate MW by resource)
Here is the cost estimate (<-add link to the cost estimate) for the Transition Phase 1 Cluster Study.
Here is the map (<-add link) of requests being studied in the Transition Phase 1 Cluster Study.
The Transition Cluster Study is currently in the Phase 1 Cluster Study step of the study process. The Phase 1 Cluster Study began on April 19, 2025, and the expected completion date is Jan. 30, 2026. BPA will provide Cluster Study updates via Tech Forum announcement.

Next Steps

After the Transition Phase 1 Cluster Study is complete, BPA will begin the 90 Calendar Day Customer Review Period. BPA will host a Cluster Study Report Meeting in the first 10 Business Days of the Customer Review Period.

Customers can request a change to their Generator Interconnection Request within 45 Calendar Days of the start of the Customer Review Period by submitting this form (link) to GI_ClusterStudies@bpa.gov

Before the end of the Customer Review Period, customers with a request being studied in the Phase 1 Cluster Study must submit the following:

  • Redemonstration Form
  • Commercial Readiness redemonstration
    • If electing to use the Commercial Readiness Deposit option, the deposit is 10% of the cost of facilities identified in the Phase 1 Cluster Study Report, less any Commercial Readiness deposit already held by BPA. Submit Commercial Readiness Deposit information to CRDepositAdmins@bpa.gov
  • Site Control redemonstration
  • Dynamic models in .dyd format

BPA will use reasonable efforts to determine if a Phase 1 Cluster Restudy is necessary no later than 30 business days after the end of the Customer Review Period.

History

BPA determined that any requests received after Nov. 22, 2023 would not be eligible for the transition cluster study and would need to be resubmitted for the post-transition cluster study. On Sept. 23, 2023 BPA had X requests in the Large Generator Interconnection Queue. These requests were sorted into Bypass, Late Stage, and Transition Cluster groups.

Late Stage and Transition Cluster Requests were required to submit transition applications including Site Control and Commercial Readiness requirements. The transition applications were due Sept. 28, 2024.

BPA validated transition applications until March 5, 2025. On March 5, BPA held a Cluster Scoping Meeting to discuss the requests received, the proposed grouping of the requests, and next steps for the study process. The meeting materials for the Cluster Scoping Meeting can be found here.

BPA processed study deposits and Phase 1 Cluster Study Agreements until April 19, 2025, when the Phase 1 Cluster Study began. The Phase 1 Cluster Study was scheduled to complete Aug. 16, 2025, but a delay notice was sent on July 23, 2025 that set the new scheduled completion date to Jan. 30, 2026.