FERC Order 2023 introduced graduated site control thresholds for CAISO's cluster study queue. Operating ~80% of California's grid plus a small part of Nevada, CAISO's compliance filing (ER24-2042) was accepted May 2025 with an effective date of June 12, 2024. Here's everything you need for a deficiency-free cluster study application.
Under FERC Order 2023, CAISO requires increasing site control coverage at each cluster study milestone. Options count at full weight (1.0) through cluster study phases, begin discounting at Facilities Study (0.75), and are excluded entirely at IA execution.
| Queue Stage | Coverage Threshold | Options Allowed | Option Weight | Encumbrance Policy |
|---|---|---|---|---|
| Pre-Application | 0% | Yes | 1.0 | Flag |
| Cluster Study Ph1 | 90% | Yes | 1.0 | Flag |
| Cluster Study Ph2 | 90% | Yes | 1.0 | Flag |
| Facilities Study | 90% | Yes | 0.75 | Disqualify |
| IA Execution | 100% | No | 0.0 | Disqualify |
| Commercial Operation | 100% | No | 0.0 | Disqualify |
Eligible instruments at IA execution: fee simple, executed lease, easement, ROW agreement, BLM ROW grant. CAISO compliance filing ER24-2042, effective June 12, 2024.
For the full cross-RTO comparison, see FERC Order 2023 Thresholds by RTO and Stage.
Cluster 16 Application Window Opens
90% site control required at cluster study entry
Cluster Study Phase 1 Begins
Projects batched into cluster groups. 90% coverage must be maintained
Cluster Study Phase 2
Refined study results. 90% site control threshold maintained
Facilities Study
90% threshold. Options discounted to 0.75 weight. Encumbrances now disqualify
IA Execution
100% site control with executed instruments only — no options
16M acres of agricultural preserves. Non-renewal triggers a 10-year waiting period. The most common CAISO site control deficiency — and how to avoid it.
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Per-stage thresholds, eligible instruments, option weights, and encumbrance policies for all 7 RTOs under FERC Order 2023.
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How option expirations drop coverage below CAISO thresholds and the conversion timeline your land team needs before IA execution.
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Parcels under Williamson Act agricultural preserves require non-renewal notice — triggering a 10-year waiting period that outlasts most queue timelines.
12 questions covering FERC Order 2023, the 5-filter audit, SNDA requirements, Williamson Act, and CAISO cluster study deadlines.
California's Williamson Act covers 16 million acres of agricultural preserves. Filing a non-renewal notice triggers a 10-year waiting period before the land can be converted — far longer than any cluster study timeline. This is the single most common CAISO site control deficiency. Land teams must verify Williamson Act status before signing options in the Central Valley and desert counties.
BLM Right-of-Way permits are a primary instrument type for CA desert counties (Riverside, San Bernardino, Imperial, Kern). Minimum BLM ROW status requirements increase by queue stage: applied at cluster entry, accepted at Phase 2, environmental review at Facilities, and grant issued at IA execution. BLM processing backlogs routinely extend 18–24 months, creating a gap between queue milestones and permit status.
The Desert Renewable Energy Conservation Plan (DRECP) overlay divides the CA desert into Development Focus Areas, Right-of-Way corridors, and conservation/reserve zones. Projects sited in conservation or reserve areas are effectively killed — no amount of site control cures a DRECP conflict. Development Focus Areas and ROW corridors are viable, but require DRECP compliance documentation alongside site control filings.
Options are weighted 1.0 through cluster study phases and 0.75 at Facilities, but are excluded entirely at IA execution. If your options expire before you reach IA, coverage drops to zero on those parcels. CAISO's cluster study timeline can stretch 2–3 years, meaning options signed at project origination may not survive to IA. Land teams need 12+ months lead time to negotiate lease conversions.
Split-estate prevalence on BLM land means surface rights and mineral rights are held by different parties. A BLM ROW grant covers the surface, but outstanding mineral rights can constitute an encumbrance. At Facilities Study and beyond, where encumbrances disqualify coverage, unresolved split-estate conflicts can silently drop your site control percentage below the 90% threshold.
Note: CEQA (California Environmental Quality Act) review runs parallel to the interconnection queue but is not a site control instrument. CEQA compliance does not count toward coverage thresholds.
Zonevex parses your lease PDFs and BLM ROW documents, matches parcels to the project boundary, applies CAISO's stage-specific thresholds, flags Williamson Act and DRECP conflicts, and tells you exactly where your coverage stands — before you file.
90%
Cluster study threshold
90%
Facilities threshold
100%
IA execution
5
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