Interconnection cluster window calendar — 13 windows open now
13 interconnection and large-load deadlines are open or upcoming across the seven organised markets and FERC, as of 15 September 2026. 2 of them close within sixty days. Cluster windows are annual: a missed close is a year lost, not a week.
Assembled by Watt Street from each authority's own tariff, order and form pages where we have checked them, and from commercial calendars and law-firm notes where we have not. Every row says which. Data as of 15 September 2026. The same calendar is available over the API and MCP, with the confidence flag on every record.
Everything open or upcoming
| Queue | What closes | Closes | Standing |
|---|---|---|---|
| ERCOT | ERCOT Production Load Schedule - Resource Entity model information submission deadline ERCOT publishes real calendar cutoffs for submitting complete model information ahead of each network model production load. | 2026-10-01 | confirmed source |
| CAISO | CAISO Cluster 16 interconnection request window Interconnection requests submitted through the GRIP portal. | 2026-10-15 | confirmed source |
| ISONE | ISO-NE cluster request window Cluster study under OATT Schedules 22, 23 and 25. | 2026-11-19 | confirmed source |
| PJM | Dominion GS-5 (Virginia SCC PUR-2025-00058) - ESAs signed on or after this date carry the 14-year term From this date the GS-5 large-load tariff carries a 14-year minimum term, alongside the reported 85% of contracted transmission demand minimum and $1… | 2027-01-01 | unconfirmed source |
| MISO | MISO DPP-2026 Definitive Planning Phase application deadline Attachment X of the tariff and BPM-015. | 2027-09-10 | confirmed source |
| ERCOT | ERCOT Batch 1 large load interconnection - applications not yet dated Successor cycle to Batch Zero under PGRR145. | No date published yet | confirmed source |
| ERCOT | ERCOT generation interconnection — rolling Not FERC-jurisdictional. | Open all year — no cut-off | confirmed source |
| FERC | FERC large-load show cause — stakeholder comments on RTO responses Comments on the six RTO/ISO responses to the FPA section 206 show-cause orders of 18 June 2026 (PJM EL26-67, SPP EL26-68, NYISO EL26-69, MISO EL26-70… | No date published yet | unconfirmed source |
| FERC | FERC RM26-4 — generic large-load rulemaking Still at ANOPR stage. | No date published yet | confirmed source |
| FERC | Georgia PSC - Georgia Power must file large-load contracts 30 days before execution A standing obligation rather than a dated one: large-load contracts must be filed with the commission at least 30 days before they are executed. | No date published yet | confirmed source |
| NYISO | NYISO cluster request window Class Year deliverability construct plus the new cluster process. | No date published yet | confirmed source |
| SPP | SPP 2028 CPP Interconnection Cluster Study (ICS) application window Definitive Interconnection System Impact Study cluster, post Order 2023 compliance. | No date published yet | confirmed source |
| ERCOT | Texas SB 6 - large load curtailment protocol and equipment (PURA section 39.170(a)) All new large-load interconnections must carry ERCOT-controlled curtailment equipment. | Open all year — no cut-off | confirmed source |
Known to be coming, no date published
These are real windows with no announced date. They are listed rather than omitted, because knowing a window exists and is unannounced is itself planning information — and because a placeholder date is something somebody would diary.
| Queue | What | What we know | Source |
|---|---|---|---|
| ERCOT | ERCOT Batch 1 large load interconnection - applications not yet dated | Successor cycle to Batch Zero under PGRR145. | link |
| ERCOT | ERCOT generation interconnection — rolling | Not FERC-jurisdictional. | link |
| FERC | FERC large-load show cause — stakeholder comments on RTO responses | Comments on the six RTO/ISO responses to the FPA section 206 show-cause orders of 18 June 2026 (PJM EL26-67, SPP EL26-68, NYISO EL26-69, MISO EL26-70, CAISO EL26-71, ISO-NE EL26-72). | link |
| FERC | FERC RM26-4 — generic large-load rulemaking | Still at ANOPR stage. | link |
| FERC | Georgia PSC - Georgia Power must file large-load contracts 30 days before execution | A standing obligation rather than a dated one: large-load contracts must be filed with the commission at least 30 days before they are executed. | link |
| NYISO | NYISO cluster request window | Class Year deliverability construct plus the new cluster process. | link |
| SPP | SPP 2028 CPP Interconnection Cluster Study (ICS) application window | Definitive Interconnection System Impact Study cluster, post Order 2023 compliance. | link |
| ERCOT | Texas SB 6 - large load curtailment protocol and equipment (PURA section 39.170(a)) | All new large-load interconnections must carry ERCOT-controlled curtailment equipment. | link |
How to read the standing column
Confirmed means the date was read off the authority's own tariff, order, docket or form page, and the check itself is recorded — what was read, what was corrected, and what could not be reached. Unconfirmed means we have it from a commercial calendar, a law-firm note or trade press and have not yet made that check. Disputed means we made the check and the authority's own documents contradicted the date we held, so we withdrew it rather than leave it standing. We publish all three, labelled, because the alternative is publishing only what we have checked and leaving you unaware that the rest exists. Nothing here is legal or filing advice — read the source before you diary a date.
Put this on your own page. The counter is available as a free embed — one line of HTML, no key, and it stays right without you touching it. Get the snippet.
Found one we have wrong or missing? Email [email protected]. Corrections are published in our corrections log, including our own.
Watch a queue rather than remember it
A county report puts the windows that bind a specific site next to what is actually queued there, with the date each figure was true on every page.